Practice Tests

Which of the following technologies can replace leased lines, such as T-1s, by multiplexing signals as packets switched through virtual circuits in a cloud? A. E-1s B. Frame relay C. ATM D. PPP

. Frame relay is a packet switching service that uses a single leased line to replace multiple leased lines by multiplexing traffic through a cloud. The service can create virtual circuits connecting the subscriber's network to multiple destinations, eliminating the need for a dedicated leased line to each remote site. An E-1 is the European equivalent to a T-1 leased line, which does not replace multiple T-1s. Asynchronous Transfer Mode (ATM) is a cell-switching WAN technology, and Point-to-Point Protocol (PPP) is a protocol that provides a data link layer connection between two end systems. Neither is a replacement for multiple T-1s.

Which of the following wireless security protocols uses CCMP for encryption? A. WEP B. WPA C. WPA2 D. 802.1X

. CCMP, the full name of which is Counter Mode Cipher Block Chaining Message Authentication Code Protocol, is based on the Advanced Encryption Standard (AES) and is the encryption protocol used with the Wi-Fi Protected Access II (WPA2) security protocol on wireless networks. CCMP is not used with version 1 of the WPA protocol or with Wired Equivalent Privacy. 802.1X is an authentication protocol, not used for encryption.

Which of the following reflect the media type, bandwidth capacity, and distance limitation combination of 10BASE5 Ethernet? A Cat 3 UTP/10 Mbps/100 m B Coax/10 Mbps/185 m C Coax/10 Mbps/500 m D Cat 5 UTP/100 Mbps/100 m

10BASE5 Ethernet (also known as thicknet) uses coax cable, has a bandwidth capacity of 10 Mbps, and a distance limitation of 500 m. Answer B is incorrect. 10BASE2 Ethernet (also known as thinnet) uses coax cable, has a bandwidth capacity of 10 Mbps, and a distance limitation of 185 m. Answer A is incorrect. 10BASE-T Ethernet uses Cat 3 (or higher) UTP, has a bandwidth capacity of 10 Mbps, and a distance limitation of 100 m. Answer D is incorrect. 100BASE-TX Ethernet uses Cat 5 (or higher) UTP cable, has a bandwidth capacity of 100 Mbps, and a distance limitation of 100 m.

You are starting a new job, and the company's Human Resources person has asked you to sign an acceptable use policy (AUP) regarding computer and network use. The document includes a privacy clause. Which of the following are specifications you can expect to find in this clause? (Choose all correct answers.) A. Any emails you send or receive can be monitored by the company at any time. Your selection is incorrect B. All files and data that you store on company computers must be accessible to the company for scanning and monitoring. C. All work that you perform for the company becomes the sole property of the company, including copyrights and patents. D. All hardware, software, and any proprietary data stored on the company's computers remains the property of the company.

A and B. Clauses regarding company property, including the copyrights and patents for the work performed for the company, typically do appear in an AUP but not in the privacy clause. This information would be more likely to appear in an ownership clause. The privacy clause commonly explains that the company has the right to access and monitor anything stored on its computers.

Which of the following networking concepts frequently use virtual IP addresses to provide high availability? (Choose all correct answers.) A. Clustering B. Load balancing C. Network address translation (NAT) D. NIC teaming

A and B. A high availability virtual IP address implementation is when multiple servers are identified by a single address, enabling all of the servers to receive incoming client traffic. In the case of server clustering and network load balancing arrangements, the cluster itself has a unique name and IP address, separate from those of the individual servers. Clients address themselves to the cluster, not to one of the servers in the cluster. NAT is not a high availability technology, and NIC teaming does not use virtual IP addresses.

Which of the following explains why splitting a large switched Ethernet LAN into two LANs by adding a router can help to alleviate traffic congestion and improve performance? (Choose all correct answers.) A. Adding a router reduces the amount of broadcast traffic on each of the two LANs. B. Adding a router reduces the amount of unicast traffic on each of the two LANs. C. Adding a router diverts traffic to an alternate path through the network. D. Adding a router prevents computers on one LAN from communicating with computers on another LAN.

A and B. Adding a router splits the Ethernet LAN into two LANs, creating two separate broadcast domains. Each computer, therefore, has a smaller number of broadcast messages to process. Because the network is split by the router, the amount of unicast traffic on each subnet is reduced.

Ed is troubleshooting some network performance problems. After exhausting many other possibilities, he is examining the twisted pair cable runs in the office's drop ceiling. He finds that some cables have been damaged, apparently by electricians working in that space. In some cases, the cable sheath has been split along its length, and some of the insulation on the wires inside has been scraped off as well. Which of the following types of faults might be caused by this damage? (Choose all correct answers.) A. Open circuits B. Short circuits C. Split pairs D. Transposed wires

A and B. An open circuit is caused either by a break in the wire somewhere inside the cable or a bad connection with the pin in one or both connectors. A short is when a wire is connected to two or more pins at one end of the cable or when the conductors of two or more wires are touching inside the cable. In this instance, the damage to the cables could have resulted in either condition. A split pair is a connection in which two wires are incorrectly mapped in exactly the same way on both ends of the cable. Having transposed pairs is a fault in which both of the wires in a pair are connected to the wrong pins at one end of the cable. Both of these faults are the result of incorrect wiring during installation, and they are not caused by damaged cables.

Which of the following protocols generate messages that are carried directly within Internet Protocol (IP) datagrams, with no intervening transport layer protocol? (Choose all correct answers.) A. ICMP B. IGMP C. SMTP D. SNMP

A and B. Internet Control Message Protocol (ICMP) and Internet Group Management Protocol (IGMP) are unusual in that they generate messages that are encapsulated directly within IP datagrams. Nearly all of the other TCP/IP protocols, including Simple Mail Transfer Protocol (SMTP) and Simple Network Management Protocol (SNMP), are encapsulated within one of the transport layer protocols—User Datagram Protocol (UDP) or Transmission Control Protocol (TCP)—which is encapsulated in turn within an IP datagram.

What is the difference when you specify the HTTPS:// prefix in a uniform resource locator (URL) instead of HTTP://? (Choose all correct answers.) A. The connection between the web browser and the server is encrypted. B. The browser uses a different port number to connect to the server. C. The connection uses SSL or TLS instead of HTTP.Your selection is incorrect D. The browser uses a different IP address to connect to the server.

A and B. Using the prefix HTTPS:// causes a web browser to use a different port number to establish a secure connection to the web server. Security is provided by encrypting all data using Secure Sockets Layer (SSL) or Transport Layer Security (TLS). However, SSL and TLS do not replace HTTP; they just augment it. The HTTPS:// prefix does not affect the IP address used to connect to the server.

Alice receives a call from a user who cannot connect to the company's 802.11g wireless network with a new laptop that has an 802.11ac network adapter. Other users working in the same area are able to connect to the network without difficulty. Which of the following steps can Alice perform to resolve the problem? (Choose all correct answers.) A. Install an 802.11ac wireless access point on the network. B. Change the channel used by the wireless access point. C. Install an 802.11g wireless network adapter in the user's laptop. D. Move the user closer to the wireless access point.

A and C. The 802.11ac and 802.11g wireless networking standards are fundamentally incompatible. The 802.11g access point uses the 2.4 GHz band and the user's 802.11ac laptop uses the 5 GHz band. Therefore, the only possible solutions are to install an 802.11ac access point or an 802.11g network adapter. Changing channels on the access point and moving the user will have no effect on the problem.

Which of the following are places where network wiring connections are found? (Choose all correct answers.) A. MDF B. MTBF C. IDF D. RDP

A and C. A large enterprise network will—at minimum—have demarcation points for telephone services and a connection to an Internet service provider's network. In many cases, these services will enter the building in the same equipment room that houses the backbone switch. This room is then called the main distribution frame (MDF). An intermediate distribution frame (IDF) is the location of localized telecommunications equipment such as the interface between the horizontal cabling and the backbone. Mean Time Between Failures (MTBF) and Remote Desktop Protocol (RDP) are not locations of network wiring.

Which of the following statements about cable certifiers are true? (Choose all correct answers.) A. A cable certifier eliminates the need for tools like tone generators and wiremap testers. B. Cable certifiers are the most inexpensive cable testing solution. C. Cable certifiers must be reconfigured whenever a new cable specification is standardized. D. Cable certifiers can only test copper-based cables.

A and C. Cable certifiers can detect all of the faults that tone generators and wiremap testers can detect, and they can do a great deal more, such as specify whether a cable run meets the performance specifications defined in a cable standard. When testing a new cable type, the specifications defined in the cable standard must be added to the device. Cable certifies are far more expensive than most other cable testing solution. Cable certifiers are available that support various cable media, including copper and fiber optic.

Which of the following technologies utilize access control lists to limit access to network resources? (Choose all correct answers.) A. NTFS B. LDAP C. WAP D. Kerberos

A and C. NTFS files and folder all have access control lists (ACLs), which contain access control entries (ACEs) that specify the users and groups that can access them and the specific permissions they have been granted. Wireless access points (WAPs) have access control lists that contain MAC address of the devices that are permitted to connect to the wireless network. Lightweight Directory Access Protocol and Kerberos are protocols that provide directory service communication and authentication, respectively. Neither one uses access control lists.

The change request for new graphics software that you submitted to your company's change management team has been approved. Now it is time to implement the change. Which of the following administrative tasks will most likely be the change management team's responsibility during the implementation process? (Choose all correct answers.) A. Authorizing downtime B. Notifying usersYour selection is incorrect C. Designating a maintenance windowYour selection is incorrect D. Documenting all modifications made

A and C. The change management team is usually not responsible for tasks directly involved in the implementation of the changes they approve. Therefore, they would not be the ones to notify users exactly when the change will take place or document the procedure afterward. They would, however, be responsible for providing a maintenance window, during which the change must occur, and authorizing any downtime that would be needed.

Which of the following storage area network (SAN) technologies can conceivably share the same network cabling system as a local area network (LAN)? (Choose all correct answers.) A. iSCSIYour selection is incorrect B. Fibre Channel C. FCoEYour selection is incorrect D. InfiniBand

A and C. iSCSI runs on a standard IP network, so its traffic can conceivably coexist with LAN traffic. However, the use of a quality of service (QoS) mechanism is strongly recommended, to prevent the two traffic types from interfering with each other. Fibre Channel over Ethernet (FCoE ) replaces the bottom two layers of the standard Fibre Channel network with Ethernet physical and data link layer implementations. This makes it possible to run a Fibre Channel SAN using standard Ethernet networking hardware. However, the same issues of traffic coexistence that affect iSCSI apply to FCoE as well. Standard Fibre Channel and InfiniBand SANs cannot coexist with LAN traffic on the same network cable.

Q. 175 Which of the following statements about the differences between network attached storage (NAS) and storage area networks (SANs) are true? (Choose all correct answers.) A. NAS provides file-level storage access, whereas SAN provides block-level storage access. B. NAS devices typically contain integrated iSCSI targets. C. SAN devices have an operating system, whereas NAS devices do not. D. NAS devices typically provide a filesystem, whereas SAN devices do not.

A and D. NAS devices are self-contained file servers that connect directly to a standard IP network. A NAS device provides file-level access to its storage devices, and includes an operating system and a filesystem. NAS devices are typically not iSCSI targets.

Which of the following statements about PPPoE are not true? (Choose all correct answers.) A. PPPoE encapsulates Ethernet frames within PPP packets. B. PPPoE enables multiple users on an Ethernet network to share a single Internet connection. C. PPPoE requires a server on the Ethernet network that functions as the middleman between the LAN and the Internet service provider's (ISP's) network. D. The PPPoE connection process consists of two stages: negotiation and establishment

A and D. PPPoE encapsulates PPP within Ethernet frames, not the other way around. The two stages of the PPPoE connection process are discovery and session. PPPoE does enable multiple users to share an Internet connection, and it requires a PPPoE server that initiates the PPP connection to the ISP's network.

Alice has just created a new Windows Server 2016 virtual machine using remote controls provided by a cloud service provider on the Internet. Which of the following cloud architectures is she using? (Choose all correct answers.) A. IaaS B. PaaS C. SaaS D. Public cloud E. Private cloud F. Hybrid cloud

A and D. Infrastructure as a Service (IaaS) provides the consumers like Alice with processing, storage, and networking resources that they can use to install and run operating systems and other software of their choice. In the public cloud model, one organization functions as the provider, and another organization—in this case, Alice—consumes the services of the provider. Platform as a Service (PaaS) provides consumers with the ability to install applications of their choice on a server furnished by the provider. Software as a Service (SaaS) provides consumers with access to a specific application running on the provider's servers, but the consumers have no control over the operating system, the servers, or the underlying resources. In a private cloud, the same organization that utilizes the cloud services is also the sole owner of the infrastructure that provides those services. A hybrid cloud is a combination of public and private infrastructure so that the consumer organization is only a partial owner of the infrastructure.

In addition to EAP-TLS, which of the following are also Extensible Authentication Protocol (EAP) variants that use the Transport Layer Security (TLS) protocol? A. PEAP B. EAP-PWD C. EAP-MD5 D. EAP-FAST

A and D. The Protected Extensible Authentication Protocol (PEAP) and EAP Flexible Authentication via Secure Tunneling (EAP-FAST) both use TLS tunneling to secure authentication transmissions. EAP Password (EAP-PWD) and EAP-MP5 do not use TLS for tunneling or any other purpose.

Broadcast domain

A broadcast domain is the domain in which a broadcast is forwarded. A broadcast domain contains all devices that can reach each other at the data link layer (OSI layer 2) by using broadcast. All ports on a hub or a switch are by default in the same broadcast domain. All ports on a router are in the different broadcast domains and routers don't forward broadcasts from one broadcast domain to another. since all ports on a hub or a switch are in the same broadcast domain, and all ports on a router are in a different broadcast domain.

Your department is experiencing frequent delays as users wait for images to render using their outdated graphics software package. As a result, you are planning to submit a change request for a new software product at the monthly meeting of the company's change management team. Which of the following types of information are likely to be included in your request? (Choose all correct answers.) A. The possibility of rolling back to the previous software, if necessary B. The procedure for installing and configuring the new software C. An estimate of the productivity increase realizable with the new software D. A list of software and hardware upgrades or modifications needed to run the new software

A, B, C, and D. A change management team typically requires thorough documentation for all requested changes, specifying exactly what is needed; how the change will affect the current workflow, both to the direct recipients of the change and the rest of the organization; and what ramifications might come from the change.

If you have a server with dual power supplies, each of which is connected to a separate UPS, with each UPS connected to a separate building power circuit connected to a backup generator, which of the following failures can the server survive and keep running indefinitely? (Choose all correct answers.) A. Failure of one server power supply B. Failure of one UPS C. Failure of one building power circuit D. Failure of the building backup generator

A, B, C, and D. If one of the server's power supplies fails, the other will continue to function. If one of the UPSs fails, the server will continue to run using the other. If one of the building power circuit breakers trips, the server will continue to run using the other one. If the building's backup generator fails, the server will continue to run as long as the building still has outside power.

Which of the following protocols are included in an iSCSI packet? (Choose all correct answers.) A. Ethernet B. IP C. TCP D. UDP E. None of the above

A, B, and C. iSCSI runs on a standard IP network; therefore, iSCSI messages are encapsulated using Transmission Control Protocol (TCP) at the transport layer, Internet Protocol (IP) at the network layer, and Ethernet at the data link layer. iSCSI does not use the User Datagram Protocol (UDP).

Which of the following elements must be identical in both the client and server computers to establish a remote wide area network (WAN) connection? (Choose all correct answers.) A. The WAN type B. The data link layer protocol C. The authentication method D. The operating system

A, B, and C. Although the computers don't have to use hardware made by the same manufacturer, both must use the same basic type of wide area network connection, such as a leased line, a modem and PSTN line, or an Internet connection. Both of the computers must also use the same data link layer protocol, such as PPP, to establish a remote network connection. Most remote network connections use some form of authentication mechanism, even if it is nothing more than the exchange of a user name and clear text password. To establish the remote network connection, both computers must be configured to use the same type of authentication, even if it is no authentication at all. As long as all of the other elements are in place, such as the physical layer connection and the protocols, there is no need for both of the computers involved in a remote network connection to be running the same operating system.

Which of the following types of traffic are carried by the Remote Desktop Protocol (RDP)? (Choose all correct answers.) A. Keystrokes B. Mouse movements C. Display information D. Application data

A, B, and C. RDP is a component of Remote Desktop Services, a Windows mechanism that enables a client program to connect to a server and control it remotely. RDP does not carry actual application data; it just transfers keystrokes, mouse movements, and graphic display information.

Which of the following are occurrences that are typically addressed by an IT department's incident response policies? (Choose all correct answers.) A. Denial-of-service attack B. Hard disk failure C. Electrical fire D. Server outage

A, B, and D. Attacks, hardware failures, and crashes are all events that can be addressed by incident response policies that define what is to be done to analyze and remediate the problem. An electrical fire is typically not something that would be addressed by an IT department's incident response team; it is a job for trained firefighters. Once the fire is out, the company's response falls under the heading of disaster recovery.

Which of the following are possible reasons why the 5 GHz frequency tends to perform better than the 2.4 GHz frequency on a wireless LAN? (Choose all correct answers.) A. The 5 GHz frequency has more channels than the 2.4 GHz frequency. B. The 5 GHz frequency supports longer ranges than the 2.4 GHz frequency. C. The 5 GHz frequency conflicts with fewer common household devices than the 2.4 GHz frequency. D. The 5 GHz frequency transmits at faster speeds than the 2.4 GHz frequency.

A, C, and D. The 5 GHz frequency has 23 channels available in the United States, while the 2.4 GHz frequency has only 11. Many household devices, such as cordless telephones, use the 2.4 GHz frequency band, but relatively few devices use the 5 GHz band. Higher frequencies typically support faster transmission speeds, because with all other conditions equal, they can carry more data in the same amount of time. The 5 GHz frequency typically has a shorter range than 2.4 GHz, because it is less able to penetrate barriers.

Which of the following components are typically used only for telephone cable installations, and not for data networking? (Choose all correct answers.) A. 66 blocks B. 110 blocks C. 25 pair UTP cables D. 100 pair UTP cables

A, C, and D. Voice telephone networks do not have performance requirements as strict as those of data networks, so they are less liable to suffer from crosstalk and other types of interference. As a result, installers often use larger UTP cables for telephone connections. UTP cables are available in configurations containing 25 wire pairs and 100 wire pairs in a single sheath, which enables installers to service multiple users with a single cable. The punchdown blocks for UTP data networks with 8P8C connectors are called 110 blocks. The older standard for punchdown blocks is the 66 block. Rarely used for data networking, 66 blocks are still found in many telephone service installations.

Which of the following data loss prevention terms is used to describe dangers pertaining to data while a user is loading it into an application? A. Data in-use B. Data at-rest C. Data in-process D. Data in-motion

A. Data in-use is the data loss prevention term used to describe endpoint access. Data in-motion is the term used to describe network traffic. Data at-rest describes data storage. Data in-process is not one of the standard data loss prevention terms.

Which of the following protocols uses jumbo frames to increase performance levels on storage area networks? A. Ethernet B. IP C. Fibre Channel D. iSCSI

A. Ethernet uses jumbo frames to transfer large amounts of data more efficiently. On a packet-switched network, each packet requires header data, which adds to the network's transmission overhead. Splitting large files into a great many small packets can lead to so much overhead that network efficiency is impaired. Ethernet typically restricts frame size to 1,500 bytes, but jumbo frames enable Ethernet systems to create frames up to 9,000 bytes. Frames are data link layer protocol data units, so Internet Protocol (IP), operating at the network layer, is not involved in creating them. Fibre Channel and iSCSI are specialized storage area networking protocols that do not use jumbo frames.

Clients of Ralph's company are calling to complain that when they try to access the company's website, they see an error message stating that the website has an untrusted security certificate. They are afraid that they are connecting to an unprotected site or that the site has been taken over by hackers? What must Ralph due to address this problem? A. Obtain an SSL certificate from a trusted third-party company. B. Configure the web servers to generate a self-signed certificate. C. Install a certification authority on one of the network servers. D. Explain to the clients that it is safe to bypass the error message and proceed to the website.

A. For the website's Secure Socket Layer (SSL) certificate to be trusted, it must be signed by a source that both parties in the transaction trust. Many security firms are in the business of providing SSL certificates to companies that have provided them with confirmation of their identities. This is what Ralph must do to prevent the error message from appearing to the company's clients. Creating a self-signed certificate or installing a certification authority in-house are not sufficient and are probably already the cause of the problem. Users are not likely to be convinced that everything is all right.

You are working for a company with numerous branch offices scattered around the country, and you are required to travel to these offices frequently. Each branch office has some means of accessing the network at the company headquarters. Some use frame relay, some virtual private networks, and a few even use dial-in access. During one trip, you mention to a branch office manager that you intend to connect to the headquarters network that night from your hotel room. The manager warns you that this is against company policy, but you are not so sure. Where in the company documentation should you look to confirm this? A. Remote access policies B. Service level agreement C. Acceptable use policy D. Privileged user agreement

A. Remote access policies specify when and how users are permitted to access the company network from remote locations. A service level agreement (SLA) is a contract between a provider and a subscriber specifying the guaranteed availability of the service. Acceptable use policies (AUPs) specify whether and how employees can utilize company-owned hardware and software resources. A privileged user agreement specifies the abilities and limitations of users with respect to the administrative accounts and other privileges they have been granted.

Which of the following is the term for the client that accesses an iSCSI device on a storage area network? A. Initiator B. Target C. Controller D. Adapter

A. The client side of an iSCSI implementation is called an initiator. The storage device to which the initiator connects is called a target. Controller and adapter are not terms used for iSCSI clients or servers.

Which of the following protocols provides wireless networks with the strongest encryption? A. AES B. TKIP C. EAP D. 802.1X

A. Wi-Fi Protected Access (WPA) is a wireless security protocol that was designed to replaces the increasingly vulnerable Wired Equivalent Privacy (WEP). WPA added an encryption protocol called Temporal Key Integrity Protocol (TKIP). This too became vulnerable, and WPA2 was introduced, which replaced TKIP with the stronger CCMP-Advanced Encryption Standard (CCMP-AES). Extensible Authentication Protocol and 802.1X do not provide encryption.

Which of the following is the term usually applied to a representation of network devices, automatically compiled, and containing information such as IP addresses and connection speeds? A. Network map B. Network diagramYour selection is incorrect C. Cable diagram D. Management information base

A. A network map is a depiction of network devices, not drawn to scale, with additional information added, such as IP addresses and link speeds. In most cases, network maps are automatically created by a software product, such as Nmap, that scans the network and creates a display from the information it discovers. The term network diagram is most often used to refer to a manually created document containing pictograms of network devices, with lines representing the connections between them. The diagram might be roughly similar to the actual layout of the site, but it is usually not drawn to scale. A cable diagram is a precise depiction of the cable runs installed in a site. Often drawn on an architect's plan or blueprint, the cable diagram enables network administrators to locate specific cables and troubleshoot connectivity problems. A management information base (MIB) is a component of an SNMP-based network management system that contains information about only one device; it does not depict all of the devices on the network.

Which of the following types of wiring faults cannot be detected by a wiremap tester? A. Split pairs B. Open circuits C. Short circuits D. Transposed wires

A. A wiremap tester consists of a main unit that connects to all eight wires of a UTP cable at once and a loopback device that you connect to the other end, enabling you to test all of the wires at once. A wiremap tester can detect opens and shorts, as well as transposed wires. However, it cannot detect split pairs because, in that fault, the pins are properly connected.

At which layer of the OSI reference model does DHCP snooping operate? A. Data link B. Network C. Transport D. Application

A. Although DHCP is an application layer service, which uses the UDP transport layer protocol to assign network layer IP addresses, DHCP snooping is a data link layer process in which a network switch examines incoming DHCP traffic to determine whether it originates from an authorized server and is arriving over the correct port.

Which of the following terms refers to a denial-of-service (DoS) attack that places more of a burden on the target server than that of the flood of incoming traffic? A. Amplified B. Reflective C. Distributed D. Permanent

A. An amplified DoS attack is one in which the messages sent by the attacker require an extended amount of processing by the target servers, increasing the burden on them more than simpler messages would. Reflective and distributed DoS attacks use other computers to flood a target with traffic. A reflective DoS attack is one in which the attacker sends requests containing the target server's IP address to legitimate servers on the Internet, such as DNS servers, causing them to send a flood of responses to the target. A distributed denial-of-service (DDoS) attack is one in which the attacker uses hundreds or thousands of computers, controlled by malware and called zombies, to send traffic to a single server or website, in an attempt to overwhelm it and prevent it from functioning. A permanent DoS attack is one in which the attacker actually damages the target system and prevents it from functioning.

Which of the following types of interference on a twisted pair network are designed to be prevented by the twists in the wire pairs inside the cable? A. Crosstalk B. EMI C. Attenuation D. Latency

A. Crosstalk is a type of interference that occurs on copper-based networks when in a signal transmitted on one conductor bleeds over onto another nearby conductor. Twisted pair cables, which have eight or more conductors compressed together inside one sheath, are particularly susceptible to crosstalk. Twisting each of the separate wire pairs tends to reduce the amount of crosstalk to manageable levels. Twisting the wire pairs does not prevent signals from being affected by electromagnetic interference (EMI) or attenuation. Latency is a measurement of the time it takes for a signal to travel from its source to its destination.

Which of the following mechanisms for prioritizing network traffic uses a 6-bit classification identifier in the Internet Protocol (IP) header? A. Diffserv B. CoS C. Traffic shaping D. QoS

A. Differentiated services (Diffserv) is a mechanism that provides quality of service on a network by classifying traffic types using a 6-bit value in the differentiated services (DS) field of the IP header. Class of Service (CoS) is a similar mechanism that operates at the data link layer by adding a 3-bit Priority Code Point (PCP) value to the Ethernet frame. Traffic shaping is a means of prioritizing network traffic that typically works by delaying packets at the application layer. Quality of service (QoS) is an umbrella term that encompasses a variety of network traffic prioritization mechanisms.

Which of the following protocols does IPsec use to digitally encrypt packets before transmitting them over the network? A. ESP B. SSL C. AH D. MSCHAP

A. Encapsulating Security Protocol (ESP) is a protocol in the TCP/IP suite that is capable of providing encryption services for IPsec. Authentication Header (AH) provides digital integrity services for IPsec, in the form of a digital signature. Secure Sockets Layer (SSL) is a security protocol that provides encrypted communications between web browsers and servers. MSCHAP is an authentication protocol used by remote access services.

Which of the following types of patches is most typically applied to a hardware device? A. Firmware updates B. Driver updates C. Feature changes D. Vulnerability patches

A. Firmware is a type of software permanently written to the memory built into a hardware device. A firmware overrides the read-only nature of this memory to update the software. Driver updates, feature updates, and vulnerability patches are typically applied to software products, such as applications and operating systems.

Which of the following security protocols can authenticate users without transmitting their passwords over the network? A. Kerberos B. 802.1XYour selection is incorrect C. TKIP D. LDAP

A. Kerberos is a security protocol used by Active Directory that employs a system of tickets to authenticate users and other network entities without the need to transmit credentials over the network. IEEE 802.1X does authenticate by transmitting credentials. Temporal Key Integrity Protocol (TKIP) and Lightweight Directory Access Protocol (LDAP) are not authentication protocols.

Which of the following RAID levels does not provide fault tolerance? A. RAID 0 B. RAID 1 C. RAID 5 D. RAID 10

A. Redundant Array of Independent Disks (RAID) is a technology for storing data on multiple hard disk drives, providing fault tolerance, increased performance, or both. The various RAID levels provide different levels of functionality and have different hardware requirements. RAID 0 uses data striping only (blocks written to each disk in turn), which does not provide any form of fault tolerance. RAID 1 provides disk mirroring. RAID 5 combines disk striping with distributed storage of parity information. RAID 10 creates mirrored stripe sets. These three levels all provide fault tolerance.

Which of the following commands can Ralph use to display the number of bytes that a Windows workstation has transmitted? A. netstat B. tcpdump C. ipconfig D. iptables

A. Running netstat with the -e parameter on a Windows workstation displays Ethernet statistics, including the number of bytes and packets the workstation has sent and received. The ipconfig command displays TCP/IP configuration data; it does not display network traffic statistics. The tcpdump and iptables commands both run only on Unix and Linux workstations.

Alice has a network with a Domain Name System (DNS) server, a proxy server, and an Internet router. A user is complaining that she suddenly can't connect to hosts on her own local area network (LAN) and other internal LANs, and she can't access hosts on the Internet. What is the likeliest problem? A. The user's local configuration B. The proxy server C. The DNS server D. The router

A. Since only one user is reporting the problem, the user's computer and its configuration are the likeliest suspect components. A DNS, proxy, or router problem would affect more than one user.

Which of the following was created to provide logging services for the Unix sendmail program? A. syslog B. netstat C. SNMP D. CARP

A. Syslog is a standard designed to facilitate the transmission of log entries generated by a device or process, such as the sendmail SMTP server, across an IP network to a message collector, called a syslog server. Netstat is a program that displays status information about a system's network connections; it does not provide logging services. SNMP is a protocol that carries network management information from agents to a central console; it was not created specifically for sendmail. The Cache Array Routing Protocol (CARP) enables proxy servers to exchange information; it does not provide logging services.

You are the network administrator of your company's network. Your company wants to perform baseline analysis of network-related traffic and statistics. They want to track broadcasts, cyclical redundancy check (CRC) errors, and collisions for all traffic traversing a switched network. In addition, they want to provide historical and daily reports for management. They also want to keep track of software distribution and metering. What type of network software product best meets these needs? A. Simple Network Management Protocol (SNMP) management B. Protocol analyzer C. Performance Monitor D. Network traffic monitor

A. The best solution is to implement SNMP. This includes a management console, agents, and management information bases (MIBs). SNMP allows you to track statistical network information (historical and current) and produce reports for baseline analysis and troubleshooting. Some SNMP products also allow you to track software distribution and metering. Protocol analyzers are best used for troubleshooting problems in real time and are not used for software distribution and metering. Performance Monitor is a tool that allows you to track performance statistics for one system at a time and does not include software distribution and metering. There is no such product as a network traffic monitor.

Which of the following cable types is used for Thick Ethernet network segments? A. RG-8 B. RG-58 C. RJ45 D. RJ11

A. The cable type used for Thick Ethernet segments is a coaxial cable called RG-8. RG-58 is used exclusively on Thin Ethernet segments. RJ45 is a connector type used in twisted pair cabling for data networks. RJ11 is a connector type used in twisted pair cabling for telecommunications networks.

Ralph is testing a twisted pair cable run using a tone generator and locator. When he applies the tone generator to one particular wire at one end of the cable, he fails to detect a tone at the other end. Which of the following faults has Ralph discovered? A. Open B. Short C. Split pair D. Crosstalk

A. The failure to detect a tone on a wire indicates that there is either a break in the wire somewhere inside the cable or a bad connection with the pin in one or both connectors. This condition is called an open circuit. A short is when a wire is connected to two or more pins at one end of the cable. A split pair is a connection in which two wires are incorrectly mapped in exactly the same way on both ends of the cable. Crosstalk is a type of interference caused by signals on one wire bleeding over to other wires.

Many managed switches and routers include a console port for administrative access, to which you can connect a laptop and run a terminal program to access the device's interface. Which of the following is the best term for this type of access to the device? A. Out-of-band B. In-band C. Client-to-site D. BYOD

A. The term out-of-band is used to describe any type of management access to a device that does not go through the production network. Plugging a laptop into the console port avoids the network, so it is considered to be an example of out-of-band management. In-band management describes an access method that does through the production network. Client-to-site is a type of VPN connection, and Bring Your Own Device (BYOD) is a policy defining whether and how users are permitted to connect their personal devices to the network.

Alice is working the help desk when a user calls and reports that she is unable to connect to the Internet. Which of the following steps is the one Alice is least likely to perform first when troubleshooting the problem? A. Check the configuration of the router connecting the LAN to the Internet. B. Ask the user if she can access resources on the local network. C. Check to see if anyone else is experiencing the same problem. D. Check the user's job title to see if she is an important person in the company.

A. There are many possible causes for the problem that are more likely than a router configuration error, so this is not something Alice would check first. Asking if the user can access the local network attempts to isolate the problem. If she cannot, the problem could be in her computer; if she can, then the problem lies somewhere in the Internet access infrastructure. If other users are experiencing the problem, then the issue should receive a higher priority, and Alice knows that the problem does not lie in the user's computer. While it might not be the first thing she checks, it is a political reality that higher ranking users get preferential treatment.

After switching from a standard PSTN telephone system to a Voice over IP system, users are complaining of service interruptions and problems hearing callers at certain times of the day. After examining the network traffic, you determine that traffic levels on the Internet connection are substantially higher during the first and last hours of the day, the same times when most of the users experienced their problems. Which of the following solutions can provide more reliable VoIP service during peak usage times? A. Implement traffic shaping. B. Implement load balancing.Your selection is incorrect C. Upgrade the LAN from Fast Ethernet to Gigabit Ethernet. D. Replace the router connecting the LAN to the Internet with a model that supports SNMP.

A. Traffic shaping is a technique for prioritizing packets by buffering packets that are not time sensitive for later transmission. You can use this technique to give VoIP packets priority over other types of traffic. Load balancing can conceivably improve the performance of a server, but it cannot help to relieve traffic congestion on the Internet link. The traffic congestion is on the Internet connection, not the LAN, so upgrading to Gigabit Ethernet will not help. SNMP is a protocol used by network management products; it will not relieve the traffic congestion problem.

Classless Inter-Domain Routing (CIDR) is a standard for IP addressing that includes the ability to create subnets using any number of IP address bits, rather than using 8-bit blocks. Which of the following terms describes this ability? A. VLSM B. APIPA C. VLAN D. EUI-64

A. Variable-length subnet masking (VLSM) describes the process of subnetting a network address by assigning an arbitrary number of host bits as subnet bits, providing administrators with great flexibility over the number of subnets created and the number of hosts in each subnet. Automatic Private IP Addressing (APIPA) is the process by which a DHCP client assigns itself an IP address when no DHCP servers are accessible. Virtual local area networks (VLANs) are logical structures used to create separate broadcast domains on a large, switched network. Extended Unique Identifier-64 (EUI-64) is an addressing method used to create IPv6 link local addresses out of media access control (MAC) addresses.

At which layer of the Open Systems Interconnection (OSI) model do wireless range extenders operate? A. Physical B. Data link C. Network D. Transport E. Session F. Presentation G. Application

A. Wireless range extenders are physical layer devices that receive signals from wireless access points and network adapters and retransmit them, enabling devices to connect that are farther apart than the network would normally support. Because the extenders do not process the packets in any way, but just retransmit the signals, they do not operate at any layer above the physical.

What is the distance limitation of 100GBASE-ER4? A 40 km B 25 km C 10 km D 300 m

Answer A is correct. 10GBASE-ER and 10GBASE-EW both use single-mode fiber (SMF) as their media type, have a bandwidth capacity of 10 Gbps, and a distance limitation of 40 km. Also, 100GBASE-ER4 uses SMF as its media type, has a bandwidth capacity of 100 Gbps, and a distance limitation of 40 km. 10GBASE-LW uses single-mode fiber (SMF) as its media type, has a bandwidth capacity of 10 Gbps, and a distance limitation of 10 km. 10GBASE-SW uses multimode fiber (MMF) as its media type, has a bandwidth capacity of 10 Gbps, and a distance limitation of 300 m.

Approximately how many addresses are provided by a Class B scheme? A 65,000 B 35,000 C 254 D 16,000,000

Answer A is correct. A Class B address accommodates approximately 65,000 addresses. This is why subnetting is so important. You cannot have a successful network with more than approximately 500 systems in one subnet. Answer D is incorrect. 16,000,000 is the approximate number supported in a Class A. Answer C is incorrect. A Class C supports 254 addresses. Answer B is incorrect. There is no class that supports approximately 35,000 addresses.

Which of the following DNS record types provides authoritative information about a DNS zone (for example, the e-mail address of a DNS zone's administrator, the zone's primary name server, and various refresh timers)? A SOA B A C CNAME D MX

Answer A is correct. A Start of Authority (SOA) record provides authoritative information about a DNS zone, such as: e-mail contact information for the zone's administrator, the zone's primary name server, and various refresh timers. Answer D is incorrect. A Mail Exchange (MX) record maps a domain name to an e-mail (or message transfer agent) server for that domain. Answer C is incorrect. A Canonical Name (CNAME) record is an alias of an existing record, thus allowing multiple DNS records to map to the same IP address. Answer B is incorrect. An Address (A) record is used to map a hostname to an IPv4 address.

A T3 connection is an example of which WAN type? A Leased line B Circuit switched C Cell switched D Packet switched

Answer A is correct. A T1 and T3 are both examples of a leased line. Frame Relay is an example of a packet-switched WAN, and ISDN is an example of circuit switched. ATM is an example of cell switched.

If multiple wireless access points exist in a wireless LAN (WLAN), what percentage of coverage overlap should the access points have? A 10 to 15 percent B 20 to 30 percent C Approximately 50 percent D 75 percent

Answer A is correct. A WLAN with multiple access points should be setup such that users can roam from one access point's coverage area to another access point's coverage area, without losing connectivity. Therefore, a design best practice for WLANs is to have 10 - 15 percent overlap in coverage areas. You would not want more than 15 percent of coverage overlap, because that would unnecessarily reduce your overall coverage area.

What is the best possible value for administrative distance? A 0 B 170 C 255 D 1

Answer A is correct. Administrative distance is the believability of a route. The best score is 0, and the worst is 255.

A Microsoft Windows® PC is configured to obtain its IP address via DHCP. If the PC is unable to contact a DHCP server, the PC automatically assigns itself an IP address in what range? A 169.254.0.0 - 169.254.255.255 B 172.16.0.0 - 172.31.255.255 C 10.0.0.0 - 10.255.255.255 D 192.168.0.0 - 192.168.255.255

Answer A is correct. All of the address ranges listed are private IP address ranges. However, the 169.254.0.0 - 169.254.255.255 address range is used by the Automatic Private IP Addressing (APIPA) feature. APIPA allows a network device to self-assign an IP address from the 169.254.0.0 - 169.254.255.255 IP address range. Note that this range is not routable, while the other listed private IP address ranges are routable.

An IP version 6 (IPv6) address contains how many bits? A 128 B 48 C 32 D 8

Answer A is correct. An IPv6 address has eight fields. Each field contains four hexadecimal digits. Each hexadecimal digit is made up of four bits. Therefore, the number of bits in an IPv6 address can be calculated as follows: 4 bits per digit * 4 digits per field * 8 fields = 128 bits. A Byte contains eight bits. An IP version 4 (IPv4) address contains 32 bits. A Media Access Control (MAC) address contains 48 bits.

BGP's path selection is solely based on autonomous system hops. A False B True

Answer A is correct. BGP's path selection is not solely based on autonomous system hops. BGP has a variety of other parameters that it can consider. However, none of those parameters are based on link speed.

You have a Layer 2 switch. You have left all ports in the default VLAN. You connect five workstations. How many broadcast domains exist on this switch? A 1 B 0 C 5 D 2

Answer A is correct. By default, there is one broadcast domain on the switch. If you create additional VLANs, this will create additional broadcast domains.

Subnetting extends a classful subnet mask of an IP network to create additional subnets. However, what IP addressing approach removes bits from a classful subnet mask, to summarize multiple classful networks? . A CIDR B APIPA C Anycast D EUI-64

Answer A is correct. Classless Inter-Domain Routing (CIDR) shortens a classful subnet mask by removing 1s from the classful mask. As a result, CIDR allows contiguous classful networks to be aggregated. CIDR could be used by a service provider to aggregate multiple classful IP address spaces under their administration. Answer D is incorrect. The Extended Unique Identifier (EUI-64) format can be used to cause a router to automatically populate the low-order 64 bits of an IPv6 address, based on an interface's Media Access Control (MAC) address. Answer C is incorrect. Anycast is an IPv6 data flow, in which multiple devices can be assigned a single IPv6 address. An anycast communication flow is one-to-nearest (from the perspective of a router's routing table). Answer B is incorrect. Automatic IP Address Assignment (APIPA) is a non-routable automatically assigned IP address in the range 169.254.0.0 - 169.254.255.255.

Identify the antenna type, referred to in wireless LAN (WLAN) design, that is a theoretical antenna that radiates an equal amount of power in all directions (in a spherical pattern), and is said to have a gain of 0 dBi. A Isotropic B Yagi C Sector D Unidirectional

Answer A is correct. Gain is commonly measured using the dBi unit of measure. In this unit of measure, the "dB" stands for decibels, and the "i" stands for isotropic. A decibel, in this context, is a ratio of radiated power to a reference value. In the case of dBi, the reference value is the signal strength (that is, the power) radiated from an isotropic antenna, which represents a theoretical antenna that radiates an equal amount of power in all directions (in a spherical pattern). An isotropic antenna is considered to have a gain of 0 dBi. Answer D is incorrect. A unidirectional antenna can focus its power in a specific direction, thus avoiding potential interference with other wireless devices and perhaps reaching greater distances than those possible with an omnidirectional antenna. Answer B is incorrect. A Yagi antenna is a type of directional antenna. Answer C is incorrect. A sector antenna provides a pie-shaped coverage area.

Given a subnet mask of 255.255.192.0, what is the corresponding prefix notation? A /18 B /22 C /16 D /26

Answer A is correct. Given a subnet mask of 255.255.192.0, you should recognize the first two octets, each containing a value of 255, represent sixteen ones. To those 16 ones, you add two additional binary ones to create a decimal number of 192 (that is, 128 + 64 = 192). The sum of sixteen and two equals eighteen, which is the number used in the prefix (also known as slash) notation. Answer D is incorrect. The prefix notation of /26 equates to a dotted decimal subnet mask of 255.255.255.192. Answer B is incorrect. The prefix notation of /22 equates to 255.255.252.0. Answer C is incorrect. The prefix notation of /16 is the classful subnet mask of 255.255.0.0.

Which type of unshielded twisted pair (UTP) cable is commonly used for 1000BASE-T Ethernet networks and is often made of relatively thick conductors (for example, 22 gauge or 23 gauge wire) and thick insulation? A Category 6 B Category 6a C Category 3 D Category 5 E Category 5e

Answer A is correct. Like Cat 5e cable, Category 6 (Cat 6) cable is commonly used for 1000BASE-T Ethernet networks. Some Cat 6 cable is made of thicker conductors (for example, 22 gauge or 23 gauge wire), although some Cat 6 cable is made from the same 24 gauge wire used by Cat 5 and Cat 5e. Cat 6 cable does have thicker insulation and offers reduced crosstalk, as compared with Cat 5e.

What is a routing protocol that is used for moving prefixes back and forth between different autonomous systems? A BGP B OSPF C RIP D IS-IS

Answer A is correct. OSPF, RIP, and IS-IS are all examples of IGPs. Protocols that are designed to route within an autonomous system. BGP is an EGP; it is designed to share prefix information between these systems.

Which IEEE standard, supported on some Ethernet switches, requires a user to authenticate themselves before gaining access to the rest of the network? A 802.1X B 802.1Q C 802.3at D 802.3af

Answer A is correct. The IEEE 802.1X standard specifies a method of enforcing user authentication. For example, a PC (that is, the supplicant) that wishes to gain access to a network via an Ethernet switch (that is, the authenticator) must provide appropriate credentials to a RADIUS server (that is, the authentication server). IEEE 802.3af and IEEE 802.3at are both Power over Ethernet (PoE) standards. IEEE 802.1Q is an Ethernet trunking standard.

What is the administrative distance of OSPF in a Cisco network? A 110 B 120 C 170 D 200

Answer A is correct. The administrative distance for RIP is 120. OSPF is 110. Internal BGP is 200. External EIGRP is 170.

What specification identifies the cable television frequencies dedicated to data transmission? A DOCSIS B TDM C DSLAM D HFC

Answer A is correct. The frequencies dedicated to data transmission are specified by a Data-Over-Cable Service Interface Specification (DOCSIS) version. Answer B is incorrect. Time Division Multiplexing (TDM) is a technology that allows multiple conversations to share the same transmission medium. Answer D is incorrect. Cable television companies have a well established and wide reaching infrastructure for television programming. This infrastructure might contain both coaxial and fiber optic cabling. Such an infrastructure is called a hybrid fiber-coax (HFC) distribution network. Answer C is incorrect. A DSL Access Multiplexer (DSLAM) is a device often located at a telephone central office (CO) that terminates and aggregates multiple DSL connections from customers.

If you need to create at least 58 subnets, how many bits must you use for subnetting? A 6 B 3 C 4 D 5

Answer A is correct. The number of subnets that can be created is the number of bits used as the exponent to the number 2. So here, 2 raised to the 5th power is 32 subnets. 2 raised to the 6th power is 64. 2 raised to the 4th power is 16, and 2 raised to the 3rd power is 8.

Which component of an IP address dictates how many bits of the 32-bit address are the network portion versus the host portion? A Subnet mask B Default gateway C MTU D DNS address

Answer A is correct. The subnet mask dictates the network and host portion. Answer B is incorrect. The default gateway is the local router for the subnet. Answers D and C are incorrect. The DNS address is used to provide name resolution, and the MTU is the largest size packet acceptable on the media.

Which IPv6 address type is indicated by an address beginning with the hex characters FF? A Multicast B Anycast C Link-local D Globally routable unicast

Answer A is correct. There are a few IPv6 address types, and the most common ones include globally routable unicast addresses (2000 to 3999), link-local (FE80), and multicast (FF).

What is another name used to reference the functions provided by the Provider Edge (PE) router? A ELSR B CE C LSR D P

Answer A is correct. There are many different MPLS elements, including the Customer Premises Equipment (CPE), Customer Edge (CE), Edge Label Switch Router (ELSR), Provider Edge (PE), Label Switch Router (LSR), and Provider (P) routers. The PE router and the ELSR are different terms for the same device.

Identify one of the following that acts as a digital modem (that is, a device that connects to a digital circuit and can distinguish between various DS0s on that digital circuit). A CSU/DSU B DSLAM C NT1 D TE1

Answer A is correct. When a digital circuit comes into a customer's location, the circuit is terminated on a device called a Channel Service Unit/Data Service Unit (CSU/DSU). A CSU/DSU can distinguish between data arriving on various DS0s and can be thought of as a digital modem. Answer B is incorrect. A Digital Subscriber Line Access Multiplexer (DSLAM), which is often located in a telephone company's central office (CO), acts as an aggregation point for multiple DSL connections going out to subscribers. Answer C is incorrect. An NT1 is an ISDN device that interconnects a 4-wire ISDN circuit with a 2-wire ISDN circuit. Answer D is incorrect. A Terminal Endpoint 1 (TE1) is a device (such as an ISDN phone) that natively supports ISDN.

What media type is used by 1000BASE-ZX? A SMF B MMF C Cat 6a D Cat 6

Answer A is correct. With a distance limitation of 70 km, 1000BASE-ZX uses single-mode fiber (SMF). With a distance limitation of 100m, 10GBASE-T uses Cat 6a (or higher) UTP. While Cat 6 UTP should not be used in 10GBASE-T networks, Cat 6 UTP and Cat 5e UTP can be used in 1000BASE-T networks. Also, Cat 6 UTP (but not Cat5e UTP) can be used in 1000BASE-TX networks. Several Ethernet standards use multimode fiber (MMF). As a few examples, 100BASE-FX, 1000BASE-LX, 10GBASE-SR, 10GBASE-SW, and 100GBASE-SR10 can all use MMF. Note that 1000BASE-LX can alternately use SMF. Also, several Ethernet standards use single-mode fiber (SMF). As a few examples, 1000-BASE-LX, 1000BASE-LH, 1000BASE-ZX, 10GBASE-LR, 10GBASE-ER, 10GBASE-LW, 10GBASE-EW, 100GBASE-LR4, and 100GBASE-ER4 can all use SMF. Note that 1000BASE-LX can alternately use MMF.

What class of IP address is 172.16.1.2? A Class B B Class A C Class D D Class C

Answer A is correct. You can determine the class of an IP address by examining its first octet. Since 172 is in the range 128 - 191, it is a Class B IP address. Answer B is incorrect. An IP addresses whose first octet is in the range 1 - 126 is a Class A IP address. Answer D is incorrect. An IP address whose first octet is in the range 192 - 223 is a Class C IP address. Answer C is incorrect. An IP address whose first octet is in the range 224 - 239 is a Class D IP address. Note that Class D IP addresses are never used as source IP addresses. Rather, they are only used as destination multicast addresses.

Which of the following reflect the media type, bandwidth capacity, and distance limitation combination of 10BASE-T Ethernet? A Cat 5 (or higher) UTP/100 Mbps/100 m B Cat 3 (or higher) UTP/10 Mbps/100 m C Coax/10 Mbps/185 m D Coax/10 Mbps/500 m

Answer B is correct. 10BASE-T Ethernet uses Cat 3 (or higher) UTP, has a bandwidth capacity of 10 Mbps, and a distance limitation of 100 m. Answer C is incorrect. 10BASE2 Ethernet (also known as thinnet) uses coax cable, has a bandwidth capacity of 10 Mbps, and a distance limitation of 185 m. Answer D is incorrect. 10BASE5 Ethernet (also known as thicknet) uses coax cable, has a bandwidth capacity of 10 Mbps, and a distance limitation of 500 m. Answer A is incorrect. 100BASE-TX Ethernet uses Cat 5 (or higher) UTP cable, has a bandwidth capacity of 100 Mbps, and a distance limitation of 100 m.

What is the distance limitation of 10GBASE-ER? A 300 m B 40 km C 25 km D 10 km

Answer B is correct. 10GBASE-ER and 10GBASE-EW each use single-mode fiber (SMF) as their media type, have a bandwidth capacity of 10 Gbps, and a distance limitation of 40 km. Also, 100GBASE-ER4 uses SMF as its media type, has a bandwidth capacity of 100 Gbps, and a distance limitation of 40 km.10GBASE-LW uses single-mode fiber (SMF) as its media type, has a bandwidth capacity of 10 Gbps, and a distance limitation of 10 km.10GBASE-SW uses multimode fiber (MMF) as its media type, has a bandwidth capacity of 10 Gbps, and a distance limitation of 300 m.

Identify the purpose of a DHCP scope. A A scope is a hardcoded assignment of an IP address that will be assigned to a DHCP client with a specific MAC address. B A scope acts as a pool of IP addresses from which a DHCP server can assign IP addresses to DHCP clients. C A scope is a temporary IP address assignment that a DHCP server assigns to a DHCP client. D A scope is the name given to IP address information that can be assigned via DHCP. Examples of scopes include: DNS server and WINS server IP addresses.

Answer B is correct. A DHCP server can be configured to assign IP addresses to devices belonging to different subnets. Specifically, the DHCP server can determine the source subnet of the DHCP request and select an appropriate address pool from which to assign an address. One of these address pools (which typically corresponds to a single subnet) is called a scope.

What type of route is manually configured in a router's routing table and tells a router where to send traffic destined for a network not in the router's routing table? A Connected route B Default static route C Dynamic route D Redistributed route

Answer B is correct. A default static route is a manually configured route, which tells the router to send traffic destined for a network not currently in the routing table out of a specified interface or to a specified IP address (known as a next-hop IP address). While a dynamic route can propagate a default static route, a dynamic route is not manually configured. A connected route is injected into a router's routing table due to one of the router's interfaces being directly connected to the network to be advertised. A redistributed route is a route advertised from one routing source to another. For example, a route learned via RIP could be redistributed into the OSPF routing process.

What virtual network device allows Microsoft Active Directory (AD) services, UNIX-based web services, and DNS services to be co-resident on the same network device? A Virtual desktop B Virtual server C Virtual switch D Virtual PBX

Answer B is correct. A virtual server allows multiple server instances (which might be running different operating systems) to reside on the same physical server. Answer A is incorrect. A virtual desktop allows a user's data to be stored in a data center, rather than on a hard drive on the user's office computer. Answer D is incorrect. A virtual private branch exchange (PBX) is usually a voice over IP (VoIP) solution, where voice is encapsulated inside data packets for transmission across a data network. Answer C is incorrect. Some virtual servers support virtual switch technology that allows you to have Layer 2 control (for example, VLAN separation and filtering) for virtual servers co-resident on a single physical server.

ATM can be considered in which of the following WAN categories? A Circuit switched B Cell switched C Packet switched D Leased line

Answer B is correct. ATM is considered a cell switched type of technology. Because it uses fixed-length cells, sometimes you will see it specified as cell switched. Leased lines are like T1 lines, for example, and ISDN is an example of circuit switched. Here, cell switched is the best answer.

Which of the following address ranges is not routable? A 192.168.0.0 - 192.168.255.255 B 169.254.0.0 - 169.254.255.255 C 172.16.0.0 - 172.31.255.255 D 10.0.0.0 - 10 255.255.255

Answer B is correct. All of the address ranges listed are private IP address ranges. However, the 169.254.0.0 - 169.254.255.255 address range is used by the Automatic Private IP Addressing (APIPA) feature. APIPA allows a network device to self-assign an IP address from the 169.254.0.0 - 169.254.255.255 IP address range. Note that this range is not routable, while the other listed private IP address ranges are routable.

Which of the following DNS record types is used to map a hostname to an IPv4 address? A AAAA B A C SOA D MX

Answer B is correct. An Address (A) record is used to map a hostname to an IPv4 address. Answer A is incorrect. An IPv6 Address (AAAA) record is used to map a hostname to an IPv6 address. Answer C is incorrect. A Start of Authority (SOA) record provides authoritative information about a DNS zone, such as: e-mail contact information for the zone's administrator, the zone's primary name server, and various refresh timers. Answer D is incorrect. A Mail Exchange (MX) record maps a domain name to an e-mail (or message transfer agent) server for that domain.

A wireless LAN (WLAN) containing at least two access points (APs) is known as what type of WLAN? A SSID B ESS C BSS D IBSS

Answer B is correct. An Extended Service Set (ESS) WLAN is a WLAN containing two or more APs. Like a BSS WLAN, ESS WLANs operate in infrastructure mode. Answer C is incorrect. A Basic Service Set (BSS) WLAN uses a single AP. BSS WLANs are said to run in infrastructure mode (as opposed to ad hoc mode), because wireless clients connect to an AP, which is typically connected to a wired network infrastructure. Answer D is incorrect. An Independent Basic Service Set (IBSS) WLAN can be created without the use of an access point (AP). This type of ad hoc WLAN can be useful for temporary connections between wireless devices. For example, you might temporarily interconnect two laptop computers to transfer a few files. Answer A is incorrect. A Service Set Identifier (SSID) can be thought of as the name of a WLAN. Often, an AP will broadcast the name of a WLAN's SSID, thus allowing wireless devices to see that the WLAN is available.

A wireless LAN (WLAN) configured to work in an ad hoc fashion (that is, without requiring the use of an access point) is known as what type of WLAN? A BSS B IBSS C SSID D ESS

Answer B is correct. An Independent Basic Service Set (IBSS) WLAN can be created without the use of an access point (AP). This type of ad hoc WLAN can be useful for temporary connections between wireless devices. For example, you might temporarily interconnect two laptop computers to transfer a few files. Answer A is incorrect. A Basic Service Set (BSS) WLAN uses a single AP. BSS WLANs are said to run in infrastructure mode (as opposed to ad hoc mode), because wireless clients connect to an AP, which is typically connected to a wired network infrastructure. Answer D is incorrect. An Extended Service Set (ESS) WLAN is a WLAN containing two or more APs. Like a BSS WLAN, ESS WLANs operate in infrastructure mode. Answer C is incorrect. A Service Set Identifier (SSID) can be thought of as the name of a WLAN. Often, an AP will broadcast the name of a WLAN's SSID, thus allowing wireless devices to see that the WLAN is available.

While DHCP is not the only protocol used for dynamically assigning IP addresses to clients, it does offer a more robust set of features. Which of the following is a predecessor to DHCP, offering a reduced feature set? A ARP B BOOTP C DNS D WINS

Answer B is correct. BOOTP was developed as a method of assigning IP address, subnet mask, and default gateway information to diskless workstations. DHCP offers a more robust solution to IP address assignment than the solution offered by BOOTP. DHCP does not require a statically configured database of MAC address to IP address mappings. Also, DHCP has a wide variety of options beyond basic IP address, subnet mask, and default gateway parameters. For example, a DHCP server can educate a DHCP client about the IP address of a WINS server, or even an administrator-defined parameter (for example, the IP address of a TFTP server from which a configuration file could be downloaded). Address Resolution Protocol (ARP) is a protocol used to resolve a MAC address corresponding to a known IP address. Domain Name System (DNS) is a protocol used to resolve an IP address corresponding to a fully-qualified domain name (FQDN).

What is the technology used in an Ethernet network that features a backoff timer? A Half duplex B CSMA/CD C CSMA/CR D Full duplex

Answer B is correct. CSMA/CD permits multiple systems on an Ethernet network to communicate. Collisions, if they occur, are detected and systems retransmit. This is different from CSMA/CA, which seeks to avoid collisions altogether. Wireless networks typically feature a CSMA/CA approach and half-duplex communications.

What class of address is used for small networks with few systems that need connection? A Class D B Class C C Class E D Class M

Answer B is correct. Class C is used for small networks. Class D is used for multicast. There is no Class M. Class E is used for experimental

Which of the following (QoS) functions places traffic into different categories? A Marking B Classification C Congestion avoidance D Congestion management

Answer B is correct. Classification is the process of placing traffic into different categories. Classification does not, however, alter any bits in a frame or packet. Answer C is incorrect. If an interface's output queue fills to capacity, newly arriving packet are discarded (that is, tail dropped). To prevent this behavior, a congestion avoidance technique called Random Early Detection (RED) can be used. After a queue depth reaches a configurable level (that is, the minimum threshold), RED introduces the possibility of packet discard. If the queue depth continues to increase, the possibility of discard increases until a configurable maximum threshold is reached. After the queue depth has exceeded the maximum threshold, there is a 100 percent probability of packets being discarded. Answer D is incorrect. When a device, such as a switch or a router, receives traffic faster than it can be transmitted, the device attempts to buffer (that is, store) the extra traffic until bandwidth becomes available. This buffering process is called queuing or congestion management. Answer A is incorrect. Marking alters bits within a frame, cell, or packet to indicate how the network should treat that traffic. Marking alone does not change how the network treats a packet. Other tools (for example, queuing tools) can, however, reference those markings and make decisions based on the markings.

Routing protocols differ in the amount of time they require to fail over from a previously active route to a backup route. What is the name for this routing protocol property? A Split horizon B Convergence C Time-to-live D Poison reverse

Answer B is correct. Convergence is the amount of time required for a routing protocol to failover from a previously active route to a backup route. Answer A is incorrect. Split horizon is a feature that prevents a route learned on a router interface from being advertised back out of that same interface. Answer D is incorrect. Poison reverse is a feature that causes a route received on an interface to be advertised back out of that same interface with a metric considered to be infinite. Answer C is incorrect. Time-to-live (TTL) is a value in an IP packet's header that is decremented by one each time the packet is routed. When the TTL reaches zero, the packet is discarded.

You are designing a small office/home office (SOHO) network, and you wish to have four subnets, while maximizing the number of hosts per subnet. The network you need to subnet is 192.168.5.0/24. Which of the following is one of the four subnets you should create? A 192.168.5.16/27 B 192.168.5.64/26 C 192.168.5.32/25 D 192.168.5.8/28

Answer B is correct. Four subnets are supported with two borrowed bits, based on the formula: number of subnets = 2^s, where s is the number of borrowed bits (that is, 2^2 = 4). Since a design requirement stated that the number of hosts per subnet be maximized, you would not want to use more borrowed bits than necessary. Therefore, you should choose a 26-bit subnet mask (that is, 255.255.255.192). The block size is 64 (that is, 256 - 192 = 64). Therefore, the subnets created by subnetting the 192.168.5.0/24 network with a 26-bit subnet mask are: 192.168.5.0/26 192.168.5.64/26 192.168.5.128/26 192.168.5.192/26

In a wireless LAN (WLAN), what might cause a "multipath" problem? A Mismatched SSIDs B A metal file cabinet C A cordless phone D Mismatched wireless security standards

Answer B is correct. In electromagnetic theory, radio waves cannot propagate through a perfect conductor. So, while metal filing cabinets and large appliances are not perfect conductors, they are sufficient to cause degradation of a WLAN signal. For example, a WLAN signal might hit a large air-conditioning unit, causing the radio waves to be reflected and scattered in multiple directions. Not only does this limit the range of the WLAN signal, but radio waves carrying data might travel over different paths. This multipath issue can cause data corruption. While a cordless phone (operating in the 2.4 GHz band) might cause interference in a WLAN, it would not contribute to a multipath problem. While mismatched wireless security standards or a mismatched Service Set Identifier (SSID) could prevent a wireless client from associating with a wireless access point (AP), those issues would not result in a multipath problem.

Which of the following mechanisms is considered a link-efficiency tool in QoS? A CBWFQ B LFI C Traffic shaping D WRED

Answer B is correct. LFI is the link-efficiency tool. CBWFQ is congestion management, WRED is congestion avoidance, and traffic shaping is considered policing and shaping.

Which of the following specifies a type of fiber optic cable that has a core whose diameter is large enough to transport light arriving at a variety of angles (that is, more than one mode of propagation)? A RG-58 B MMF C RG-6 D RG-59 E SMF

Answer B is correct. Multimode fiber (MMF) is a fiber optic cable type whose core has a diameter capable of transporting light arriving at different angles (that is, modes). While this type of cable is typically less expensive to manufacture (as compared to single-mode fiber), the different modes of light propagation can lead to multimode delay distortion and can corrupt data transmissions over long distances

Which of the following is a technology that allows a service provider to offer networking services to customers? A PaaS B NaaS C SaaS D HaaS

Answer B is correct. Network as a Service (NaaS) is a technology that allows a service provider to offer networking services to customers. As a result, the customers have access to network services without having the ongoing maintenance responsibilities associated with those services. Answer C is incorrect. An application service provider (ASP) provides application software access to subscribers. This service is sometimes called Software as a Service (SaaS). Answer D is incorrect. Hardware as a Service (HaaS) is a service where a company leases hardware components, and those components get upgraded over time. Answer A is incorrect. Platform as a Service (PaaS) is a technology that allows a company to use computing platforms owned and maintained by a service provider. For example, instead of a company purchasing a web server, they could provision a web server platform from a service provider.

Which of the following is a protocol that allows you to bundle multiple physical interfaces (for example, Ethernet switch interfaces) into a single logical interface? A HSRP B LACP C CARP D DSCP

Answer B is correct. One approach to providing Layer 3 redundancy is to have multiple links between devices and select a routing protocol that load balances over the links. Additionally, Link Aggregation Control Protocol (LACP) lets you assign multiple physical links to a logical interface, which appears as a single link to a route processor. Differentiated Services Code Point (DSCP) is a Layer 3 Quality of Service (QoS) marking. Both Hot Standby Router Protocol (HSRP) and Common Address Redundancy Protocol (CARP) provide Layer 3 redundancy. They do so by allowing more than one router (or multilayer switch) to act as a default gateway for a subnet.

What is a very common protocol found on dedicated leased lines? A HDLC B PPP C DSL D ADSL

Answer B is correct. PPP is very commonly used over dedicated leased lines. Answer A is incorrect. HDLC is much less popular because it lacks the robust features of PPP. Answers D and C are incorrect. ADSL and DSL are technologies used to provide high-speed WAN links themselves.

Which of the following is a technology that allows a company to use development resources owned and maintained by a service provider? A NaaS B PaaS C HaaS D SaaS

Answer B is correct. Platform as a Service (PaaS) is a technology that allows a company to use computing platforms owned and maintained by a service provider. For example, instead of a company purchasing a web server, they could provision a web server platform from a service provider. Answer D is incorrect. An application service provider (ASP) provides application software access to subscribers. This service is sometimes called Software as a Service (SaaS). Answer C is incorrect. Hardware as a Service (HaaS) is a service where a company leases hardware components, and those components get upgraded over time. Answer A is incorrect. Network as a Service (NaaS) is a technology that allows a service provider to offer networking services to customers. As a result, the customers have access to network services without having the ongoing maintenance responsibilities associated with those services.

Which of the following technologies is not typically considered for an increase in redundancy? A LACP B PAT C VRRP D GLBP

Answer B is correct. Port Address Translation is a scalability-enhancing technology. It is not thought of for redundancy. Answer A is incorrect. One form of Layer 3 redundancy is achieved by having multiple links between devices and selecting a routing protocol that load balances over the links. Link Aggregation Control Protocol (LACP) enables you to assign multiple physical links to a logical interface, which appears as a single link to a route processor. Answers C and D are incorrect. VRRP and GLBP both provide redundancy in default gateways.

What is the range for a Class A address? A 128-191 B 1-126 C 224-239 D 192-223

Answer B is correct. Remember, the Class A address range is 1 to 126 in the first octet. The simple way to remember this is the fact that the loopback address is 127. So, the Class A range goes up to this loopback address.

What is the correct formula for the calculation of the number of hosts that can exist on a given subnet? A 2^h - 4 B 2^h - 2 C 2^h D 2 x h

Answer B is correct. The number of hosts that can be accommodated on a subnet is calculated with the formula 2^h - 2. h is the number of host bits. The -2 is due to the broadcast address for the subnet and the subnet address itself.

What technology operates in the 3 kHz through 300 GHz range? A HSPA+ B Radio C LTE D Satellite

Answer B is correct. The range of frequencies (measured in Hertz [Hz], which represents the number of cycles of a waveform per second) typically considered to be in the radio frequency spectrum includes frequencies of 3 kHz through 300 GHz.

Which IPv6 address type is indicated by the first four hex characters of an address ranging from 2000 to 3999? A Multicast B Globally routable unicast C Anycast D Link-local

Answer B is correct. There are a few IPv6 address types, the most common ones include globally routable unicast addresses (2000 to 3999), link-local (FE80), and multicast (FF).

Which QoS mechanism is also referred to as hard QoS because it makes strict bandwidth reservations? A Uncontrolled services B Integrated services C Best effort D Differentiated services

Answer B is correct. Three different QoS mechanisms are commonly used: best effort, integrated services (IntServ), and differentiated services (DiffServ). Integrated services is also referred to as hard QoS because it establishes strict bandwidth reservations throughout the proposed path using the Resource Reservation Protocol (RSVP).

What is the name of the process that is used in IPv6 address autoconfiguration to form a host ID? A MAC-64 B EUI-64 C EUI-48 D MAC-48

Answer B is correct. When a device uses IPv6 address autoconfiguration, it often uses the EUI-64 process to take a device's interface MAC address and alter it to form a 64-bit host ID.

A DHCP server can be used to assign a temporary IP address to a DHCP client, as opposed to a network administrator statically configuring an IP address on that client. What is this temporary IP address assignment called? A Reservation B Lease C DHCP relay agent D Scope

Answer B is correct. When a network device is assigned an IP address from an appropriate DHCP scope, that assignment is not permanent. Rather it is a temporary assignment referred to as a lease.

What media type is used by 10GBASE-SR? A SMF B MMF C Cat 6a D Cat 6

Answer B is correct. With a distance limitation of 26 - 82 m, 10GBASE-SR uses multimode fiber (MMF). With a distance limitation of 100m, 10GBASE-T uses Cat 6a (or higher) UTP. Several Ethernet standards use multimode fiber (MMF). As a few examples, 100BASE-FX, 1000BASE-LX, 10GBASE-SR, 10GBASE-SW, and 100GBASE-SR10 can all use MMF. Note that 1000BASE-LX can alternately use SMF. Additionally, several Ethernet standards use single-mode fiber (SMF). As a few examples, 1000-BASE-LX, 1000BASE-LH, 1000BASE-ZX, 10GBASE-LR, 10GBASE-ER, 10GBASE-LW, 10GBASE-EW, 100GBASE-LR4, and 100GBASE-ER4 can all use SMF. Note that 1000BASE-LX can alternately use MMF. 10BASE2 Ethernet (also known as thinnet) uses coax cable, has a bandwidth capacity of 10 Mbps, and a distance limitation of 185 m. 10BASE5 Ethernet (also known as thicknet) uses coax cable, has a bandwidth capacity of 10 Mbps, and a distance limitation of 500 m. 100BASE-TX Ethernet uses Cat 5 (or higher) UTP cable, has a bandwidth capacity of 100 Mbps, and a distance limitation of 100 m.

Host A (with an IP address of 10.1.2.3) sends a packet to Host B (with an IP address of 192.168.1.2). What type of data flow does this represent? A Multicast B Unicast C Anycast D Broadcast

Answer B is correct. With a unicast transmission, a packet travels from a single host to a single host. With a multicast transmission, a packet travels from a single host to all members of a multicast group. With a broadcast transmission, a packet travels from a single host to all hosts in a subnet. An anycast transmission is an IPv6 data flow, where a packet travels from a single source to a single destination. However, multiple devices could share the destination's IP address, and the packet is routed to the host nearest to the source, from the perspective of a router's routing table.

Most DHCP client devices on a network are dynamically assigned an IP address from a DHCP server (that is, dynamic addressing). However, some devices (for example, servers) might need to be assigned a specific IP address. What DHCP feature allows a static IP address to MAC address mapping? A Scope B Reservation C Lease D DHCP relay agent

Answer B is correct. You can statically configure a DHCP reservation, where a specific MAC address is mapped to a specific IP address that will not be assigned to any other network device.

What is the leased line technology that has a bandwidth capacity of 44.7 Mbps? A E1 B E3 C T3 D T1

Answer C is correct. A T3 circuit has a bandwidth capacity of 44.7 Mbps. All other technologies listed are valid dedicated leased line options, but none operate at 44.7 Mbps.

A box containing a demarc is called a ______________. A TE1 B TA C NID D CSU/DSU

Answer C is correct. A demarcation point (also known as a demarc or a demarc extension) is the point in a telephone network where the maintenance responsibility passes from a telephone company to the subscriber (unless the subscriber has purchased inside wiring maintenance). This demarc is typically located in a box mounted to the outside of a customer's building (for example, a residential home). This box is called a network interface device (NID). Answer B is incorrect. A Terminal Adapter (TA) performs protocol conversion between a non-ISDN device and a Terminal Endpoint 1 (TE1) device. Answer A is incorrect. A TE1 is a device (such as an ISDN phone) that natively supports ISDN. Answer D is incorrect. When a digital circuit comes into a customer's location, the circuit is terminated on a device called a Channel Service Unit/Data Service Unit (CSU/DSU). A CSU/DSU can distinguish between data arriving on various DS0s and can be thought of as a digital modem.

What technology is typically used in conjunction with DSL? A HDLC B Metro Ethernet C PPPoE D PPP

Answer C is correct. A popular WAN technology (specifically, an Internet access technology) in residences and as businesses is digital subscriber line (DSL). Note that DSL connections typically use a variant of PPP called PPP over Ethernet (PPPoE). Answers D and A are incorrect. PPP and HDLC are not typically found in this environment. Answer B is incorrect. Metro Ethernet is a competing technology to DSL.

What device is used to create many different collision domains, thus helping to eliminate collisions in the modern network? A Router B Hub C Switch D WAN link

Answer C is correct. A switch operates at Layer 2 and functions based on Layer 2 MAC addresses. Switches are designed to create a collision domain for each connected device. This helps to eliminate collisions in the network. Answer A is incorrect. A router operates at Layer 3 and moves packets between networks based on a Layer 3 address. Most commonly, this is an IP address. 192.168.1.101 is an example of such an IP address. Answer B is incorrect. A hub operates at Layer 1 and moves bits, ignoring addressing. Answer D is incorrect. A WAN link is a connection in the network used to forward data over long distances.

What is a native VLAN? A A native VLAN is the VLAN used to identify the virtual port created by an EtherChannel. B A native VLAN is an out-of-band management VLAN. C A native VLAN is the VLAN on an IEEE 802.1Q trunk that does not have any tag bytes added. D A native VLAN is the VLAN on an IEEE 802.1Q trunk that has tag bytes added to each frame.

Answer C is correct. An IEEE 802.1Q trunk can simultaneously carry traffic for multiple VLANs. One, and only one, VLAN in a 802.1Q trunk is untagged. Frames belonging to all other VLANs each receive four tag bytes. The name of this untagged VLAN is the native VLAN. All traffic in a 802.1Q trunk is in-band. An EtherChannel virtual port does have a special VLAN type.

n a SaaS solution, where are a company's applications hosted? A With SaaS, applications are not needed. B Both onsite and offsite C Offsite D Onsite

Answer C is correct. An application service provider (ASP) provides application software access to subscribers, which are hosted offsite (at the service provider's location). This service is sometimes called Software as a Service (SaaS). SaaS is an alternative to a company locally hosting its applications (that is, hosting applications onsite).

What type of antenna radiates power at relatively equal power levels in all directions? A Sector B Unidirectional C Omnidirectional D Yagi

Answer C is correct. An omnidirectional antenna radiates power at relatively equal power levels in all directions (somewhat similar to the theoretical isotropic antenna). Answer B is incorrect. A unidirectional antenna can focus its power in a specific direction, thus avoiding potential interference with other wireless devices and perhaps reaching greater distances than those possible with an omnidirectional antenna. Answer D is incorrect. A Yagi antenna is a type of directional antenna. Answer A is incorrect. A sector antenna provides a pie-shaped coverage area.

What is the IEEE standard for the version of Power over Ethernet that offers a maximum of 32.4 Watts of power to an attached device? A 802.3af B 802.1d C 802.3at D 802.1Q

Answer C is correct. Both IEEE 802.3af and IEEE 802.3at are Power over Ethernet (PoE) standards. However, the 802.3af standard specifies a maximum wattage of 15.4 Watts, while the 802.3at standard specifies a maximum wattage of 32.4 Watts. IEEE 802.1Q is an Ethernet trunking standard. IEEE 802.1d is a standard for Spanning Tree Protocol (STP).

What variant of Domain Name System (DNS) overcomes the size limitations of the original version of DNS through the use of pseudo-resource-records? A CNAME B SOA C EDNS D FQDN

Answer C is correct. Extension Mechanisms for DNS (EDNS) supports features not supported in the original version of DNS (for example, security) while maintaining backward compatibility with the original version of DNS. Rather than using new flags in the header, which would impact backward compatibility, EDNS sends optional pseudo-resource-records between devices supporting EDNS. These records support sixteen new DNS flags. Answer D is incorrect. Fully-qualified domain name (FQDN) is an address specifying all necessary domain and sub-domain information to uniquely identify a target system. Answer B is incorrect. Start of Authority (SOA) is a DNS record that provides authoritative information about a DNS zone, such as contact information for the zone's administrator. Answer A is incorrect. Canonical Name (CNAME) is a DNS record that is an alias of an existing record, thus allowing multiple DNS records to map to the same IP address.

NetBIOS is associated with which layer of the OSI Model? This task contains the radio buttons and checkboxes for options. The shortcut keys to perform this task are A to H and alt+1 to alt+9. A Presentation B Transport C Session D Application

Answer C is correct. Network Basic Input/Output system (NetBIOS) is an application programming interface (API) developed in the early 80s to allow computer-to-computer communication on a small local area network (LAN). Later, IBM enhanced the scalability and features of NetBIOS with a NetBIOS emulator called NetBIOS Extended User Interface (NetBEUI). NetBIOS is considered to be a Session Layer (that is, Layer 5) protocol, responsible for setting up, maintaining, and tearing down sessions.

What does RIP use for a metric? This task contains the radio buttons and checkboxes for options. A Bandwidth B Cost C Hop Count D Delay

Answer C is correct. RIP is not a sophisticated routing protocol. It does not consider bandwidth when it is using its metric. The metric is a simple hop count. OSPF uses cost, which is based on bandwidth. EIGRP uses a composite metric using bandwidth and delay by default.

Which NDP message type is used by an IPv6 device? A RA B RS C NS D NA

Answer C is correct. The five different main Network Discovery Protocol (NDP) message (or packet) types are Router Solicitation (RS), Router Advertisement (RA), Neighbor Solicitation (NS), Neighbor Advertisement (NA), and Redirect. The NS message type is used by IPv6 devices to locate neighbors on the local network.

Which NDP message type is used by an IPv6 router to advertise its presence along with various link information? A NS B NA C RA D RS

Answer C is correct. The five different main Network Discovery Protocol (NDP) message (or packet) types are Router Solicitation (RS), Router Advertisement (RA), Neighbor Solicitation (NS), Neighbor Advertisement (NA), and Redirect. The RA message type is used by IPv6 routers to advertise their presence and to inform the other devices on the local network of other information.

Your company has been assigned the 192.168.1.0/24 network for use at one of its sites. You need to calculate a subnet mask that will accommodate 30 hosts per subnet, while maximizing the number of available subnets. What subnet mask will you use? A /29 B /28 C /27 D /26

Answer C is correct. The number of supported hosts in a subnet can be calculated with the formula: Number of Supported Hosts = 2^h - 2, where h is the numbered of host bits. 2^5 - 2 = 30. Therefore, five host bits would meet the design requirement. Also, since you are told that the number of available subnets should be maximized, you should not use more host bits than necessary. An IP version 4 address is 32 bits in length. Therefore, five host bits leaves 27 bits in the subnet mask (32 - 5 = 27). Therefore, a subnet mask of /27 (that is, 255.255.255.224) meets the design requirement. A /26 subnet mask (which has six host bits: 32 - 26 = 6) would support 62 (2^6 - 2 = 62) hosts. However, the number of available subnets would not be maximized. A /28 subnet mask (which has four host bits: 32 - 28 = 4) would only support fourteen (2^4 - 2 = 14) hosts. A /29 subnet mask (which has three host bits: 32 - 29 = 3) would only support six (2^3 - 2 = 6) hosts.

Which MPLS element is the provider's router that connects to the customer? A CE B P C PE D LSR

Answer C is correct. There are many different MPLS elements, including the Customer Premises Equipment (CPE), Customer Edge (CE), Edge Label Switch Router (ELSR), Provider Edge (PE), Label Switch Router (LSR), and Provider (P) routers. The PE router is the MPLS provider's router that connects to the customer.

Which QoS mechanism does not reorder packets and simply uses first-in, first-out logic? A Differentiated services B Integrated services C Best effort D Uncontrolled services

Answer C is correct. Three different QoS mechanisms are commonly used: best effort, integrated services (IntServ), and differentiated services (DiffServ). When traffic is not reordered at all and is simply forwarded as fast as possible, it is referred to as "best effort."

What technology is an IETF version of HSRP? A NAT B PAT C VRRP D GLBP

Answer C is correct. VRRP(Virtual Router Redundancy Protocol) is an IETF open standard that operates almost identically to HSRP(Hot Standby Router Protocol) from Cisco Systems. Answer D is incorrect. GLBP is another Cisco-specific technology for Layer 3 redundancy. Answers A and B are incorrect. NAT and PAT are for translating IPv4 addresses.

What is the name of the protocol used with IPv6 to learn the Layer 2 addresses that exist on the same local network? . A NAT B ARP C NDP D DHCP

Answer C is correct. Whereas the Address Resolution Protocol (ARP) is used for IPv4, IPv6 uses the Network Discovery Protocol (NDP) for a similar purpose to translate between IPv6 addresses and device Layer 2 MAC addresses.

What is the distance limitation of 10GBASE-LR? A 50 km B 40 km C 300 m D 10 km

Answer D is correct. 10GBASE-LR uses single-mode fiber (SMF) as its media type, has a bandwidth capacity of 10 Gbps, and a distance limitation of 10 km. 10GBASE-SW uses multimode fiber (MMF) as its media type, has a bandwidth capacity of 10 Gbps, and a distance limitation of 300 m. 10GBASE-ER and 10GBASE-EW both use single-mode fiber (SMF) as their media type, have a bandwidth capacity of 10 Gbps, and a distance limitation of 40 km. Also, 100GBASE-ER4 uses SMF as its media type, has a bandwidth capacity of 100 Gbps, and a distance limitation of 40 km.

What is the distance limitation of 10GBASE-SW? A 40 km B 25 km C 10 km D 300 m

Answer D is correct. 10GBASE-SW uses multimode fiber (MMF) as its media type, has a bandwidth capacity of 10 Gbps, and a distance limitation of 300 m. 10GBASE-ER and 10GBASE-EW each use single-mode fiber (SMF) as their media type, have a bandwidth capacity of 10 Gbps, and a distance limitation of 40 km. Also, 100GBASE-ER4 uses SMF as its media type, has a bandwidth capacity of 100 Gbps, and a distance limitation of 40 km. 10GBASE-LW uses single-mode fiber (SMF) as its media type, has a bandwidth capacity of 10 Gbps, and a distance limitation of 10 km.

Which of the following is a cross-connect block that was popular for cross-connecting Cat 3 UTP cables for 10 Mbps Ethernet LANs, but does not support higher-speed LAN technologies, such as 100 Mbps Ethernet LANs? A NT1 B 110 block C Smart jack D 66 block

Answer D is correct. A 66 block is cross-connect block that was traditionally used in corporate environments for cross-connecting phone system cabling. As 10 Mbps LANs started to grow in popularity, in the late 80s and early 90s, these termination blocks were used to cross-connect Cat 3 unshielded twisted pair (UTP) cabling. The electrical characteristics (specifically, cross-talk) of a 66 block, however, do not support higher-speed LAN technologies, such as 100 Mbps Ethernet networks. A smart jack is a type of network interface device that adds circuitry. This circuitry adds such features as converting between framing formats on a digital circuit (for example, a T1), supporting remote diagnostics, and regenerating a digital signal. Since 66 blocks are subject to too much cross-talk for higher-speed LAN connections, 110 blocks can be used to terminate a cable (for example, a Cat 5 cable) being used for those higher-speed LANs. An NT1 is an ISDN device that interconnects a 4-wire ISDN circuit with a 2-wire ISDN circuit.

Which type of fiber optic connector connects to a terminating device by pushing the connector into the terminating device and can be removed by depressing the tab on the connector and pulling it out of the terminating device? SC B ST C MTRJ D LC

Answer D is correct. A Lucent connector (LC) connects to a terminating device by pushing the connector into the terminating device, and it can be removed by depressing the tab on the connector and pulling it out of the terminating device.

Which of the following DNS record types points to a canonical name and is commonly used when performing a reverse DNS lookup? A MX B SOA C A D PTR

Answer D is correct. A Pointer (PTR) record points to a canonical name and is commonly used when performing a reverse DNS lookup, which is a process used to determine what domain name is associated with a known IP address. Answer C is incorrect. An Address (A) record is used to map a hostname to an IPv4 address. Answer B is incorrect. A Start of Authority (SOA) record provides authoritative information about a DNS zone, such as: e-mail contact information for the zone's administrator, the zone's primary name server, and various refresh timers. Answer A is incorrect. A Mail Exchange (MX) record maps a domain name to an e-mail (or message transfer agent) server for that domain.

What is the bandwidth of a T1 digital circuit? A 34.4 Mbps B 44.7 Mbps C 2.048 Mbps D 1.544 Mbps

Answer D is correct. A T1 digital circuit has a bandwidth of 1.544 Mbps. Answer C is incorrect. An E1 digital circuit has a bandwidth of 2.048 Mbps. Answer B is incorrect. A T3 digital circuit has a bandwidth of 44.7 Mbps. Answer A is incorrect. An E3 digital circuit has a bandwidth of 34.4 Mbps.

Which of the following is a primary benefit of a content engine? A It allows traffic to travel securely over an untrusted network (for example, the Internet). B It hides inside addresses from the public Internet. C It allows a server farm to scale. D It reduces bandwidth demand on an IP WAN

Answer D is correct. A content engine can locally store content from a remote location. This content can be served up to local clients requesting that content, without having to retrieve multiple copies of the same content over an IP WAN. Therefore, depending on traffic patterns, a content engine can significantly reduce bandwidth demand on an IP WAN. Answer B is incorrect. A proxy server receives requests from inside clients and sends requests, on behalf of those clients, to an outside network (for example, the Internet). Since these requests coming from the proxy server use the proxy server's IP address as the source IP address for packets traveling to the outside network, the inside addresses are hidden. Answer C is incorrect. A load balancer allows a server farm to scale, by adding additional servers to a server farm across which the load balancer can distribute incoming requests. Answer A is incorrect. A virtual private network (VPN) can allow traffic to flow securely across an untrusted network, such as the Internet. This security is made possible by technologies such as encryption and hashing algorithms.

Which of the following is a telephony solution that is typically based on a traditional privately-owned telephone system? A Virtual PBX B IP telephony C VoIP D Hosted PBX

Answer D is correct. A hosted private branch exchange (PBX) is a telephony system hosted by a service provider, rather than being hosted by the company using the PBX as their telephone system. Answer B is incorrect. IP telephony is a telephony solution based on native Ethernet devices (for example, IP phones). Answer C is incorrect. Voice over IP (VoIP) is a telephony solution that allows traditional telephony components (for example, analog telephones) to communicate over an IP network. Answer A is incorrect. A virtual PBX is usually a VoIP-based telephony system hosted by a service provider.

What WAN topology uses the formula n(n - 1)/ 2 to calculate the number of links required? A Partial mesh B Hub-and-spoke C Ring D Full mesh

Answer D is correct. A hub-and-spoke topology enables you to minimize costs by not directly connecting any two spoke locations. A ring topology would connect all remote locations to each other. A full mesh would also connect all remote locations, and a partial mesh topology would connect some. The full mesh provides the greatest failover because every site is connected to every other site. Unfortunately, this topology is also the most complex and expensive to implement typically. The full mesh equation for calculating the number of connections needed is n(n - 1)/2, where n is the number of sites to be connected.

Frame Relay is an example of what WAN connection type? A Cell switched B Dedicated leased line C Circuit switched D Packet switched

Answer D is correct. A packet switched connection is similar to a dedicated leased line, because most packet switched networks are always on. However, unlike a dedicated leased line, packet switched connections allow multiple customers to share a service provider's bandwidth. Frame Relay is an example of a packet switched connection. Asynchronous Transfer Mode (ATM) is often categorized as a packet switched connection. However, to be technically accurate, ATM is a cell switched connection, because ATM uses fixed-length (that is, 53 Byte) cells, as opposed to variable-length frames. Answer B is incorrect. A dedicated leased line is a logical connection interconnecting two sites. This logical connection might physically connect through a service provider's facility or a telephone company's central office. The expense of a dedicated leased line is typically higher than other WAN technologies offering similar data rates, because with a dedicated leased line a customer does not have to share bandwidth with other customers. A T1 circuit is an example of a dedicated leased line technology commonly found in North America. Answer C is incorrect. A circuit switched connection is a connection that is brought up on as as-needed basis. In fact, a circuit switched connection is analogous to phone call, where you dial a number, and a connection is established based on the number you dial. As an example, Integrated Services Digital Network (ISDN) can operate as a circuit switched connection, bringing up a virtual circuit on-demand.

ISDN is an example of which of these WAN types? A Cell switched B Packet switched C Leased line D Circuit switched

Answer D is correct. ATM is considered a cell switched type of technology. Leased lines, for example, are like T1 lines and ISDN is an example of circuit switched network.

A system on an Ethernet network detects a collision. How does it respond? A The device contacts the machine the collision occurred with. B The device contacts a central mediator on the network. C The device deletes the frame and creates another for sending. D The device retransmits after waiting for a period dictated by the backoff timer.

Answer D is correct. After a collision is detected in a CSMA/CD network, the device will resend the traffic. It will do so after waiting for a time period dictated by the backoff timer. There is no attempt to contact the other station directly, nor is there any central mediator. The frame that is re-sent is the original frame.

What is the minimum category of unshielded twisted pair (UTP) cable that can be used for 10GBASE-T networks? Category 5 B Category 5e C Category 6 D Category 6a E Category 3

Answer D is correct. Category 6a (Cat 6a), or augmented Cat 6, supports twice as many frequencies as Cat 6 and can be used for 10GBASE-T networks, which can transmit data at a rate of 10 billion bits per second (that is, 10 Gbps).

What class of address is used for experimental purposes? A Class M B Class D C Class C D Class E

Answer D is correct. Class C is used for small networks. Class D is used for multicast. There is no Class M. Class E is used for experimental purposes.

Which type of fiber optic connector, containing one fiber optic strand per connector, is connected by pushing the connector into a terminating device and can be removed by pulling the connector from the terminating device? A LC B MTRJ C ST D SC

Answer D is correct. Different literature defines an SC connector as subscriber connector, standard connector, or square connector. The SC connector is connected by pushing the connector into the terminating device, and it can be removed by pulling the connector from the terminating device. Unlike a media termination recommended jack (MTRJ) connector, which can be connected and disconnected the same way, an SC connector contains a single fiber strand per connector.

What variation of network address translation (NAT) automatically assigns an inside global address from a pool of available addresses? A Both DNAT and PAT B SNAT C PAT D DNAT

Answer D is correct. Dynamic NAT (DNAT) automatically assigns an inside global address from a pool of available addresses. Answer B is incorrect. Static NAT (SNAT) statically configures an inside global address assigned to a specific device inside your network. Answer C is incorrect. Port address translation (PAT) allows multiple inside local addresses to share a single inside global address. Sessions are kept separate through the tracking of port numbers associated with each session.

Which of the following network appliances is also known as a content switch? A VPN concentrator B Content filter C Proxy server D Load balancer

Answer D is correct. For companies with a large Internet presence (for example, a search engine company, an online bookstore, or a social networking site), a single server could be overwhelmed with the glut of requests flooding in from the Internet. To alleviate the burden placed on a single server, a content switch (also known as a load balancer) distributes incoming requests across the multiple servers in the server farm, where all of the servers contain the same data. Answer A is incorrect. While several router models can terminate a virtual private network (VPN) circuit, a dedicated device, called a VPN concentrator, could be used instead. A VPN concentrator is designed to perform the processor-intensive processes required to terminate multiple VPN tunnels. For example, running encryption algorithms, such as Advanced Encryption Standard (AES), can be very processor intensive. Answers C and B are incorrect. Some clients are configured to forward their packets, which are seemingly destined for the Internet, to a proxy server. This proxy server receives a client's request, and on behalf of that client (that is, as that client's proxy), the proxy server sends the request out to the Internet. When a reply is received from the Internet, the proxy server forwards the response on to the client. Proxy servers can also act as a content filter. Content filtering restricts clients from accessing certain URLs. For example, many companies use content filtering to prevent their employees from accessing popular social networking sites, in an attempt to prevent a loss of productivity.

What technology is similar to WiMAX and offers wireless broadband service? The maximum data rate is 84 Mbps. A Radio B LTE C Satellite D HSPA+

Answer D is correct. Like WiMAX, Evolved High-Speed Packet Access (HSPA+) is a technology offering wireless broadband service. The maximum data rate for HSPA+ is 84 Mbps. All other options listed are alternative media for wireless, but none of them match this description.

What is the name of the wireless protocol that can be used to form local area networks in the 900MHz as well as 2.4, 3.6, 5, and 60GHz frequencies? A NFC B Bluetooth C Ant+ D 802.11

Answer D is correct. Many different Internet of Things (IoT) technologies have been and are being introduced. One of these technologies that is implemented on almost all new devices is 802.11, in its various versions; it is by far the most commonly used wireless networking protocol.

What is an acceptable one-way latency in a typical VoIP network? A 300 ms B 30 ms C 50 ms D 150 ms

Answer D is correct. Network performance requirements for voice include no more than 150 ms of one-way delay, no more than 30 ms of jitter, and no more than 1 percent packet loss.

Which routing protocol uses a complex set of metrics called path vectors? A OSPF B RIP C EIGRP D BGP

Answer D is correct. OSPF and EIGRP will both use bandwidth in the default metric calculations. EIGRP also uses delay by default. BGP uses a variety of options for metric, often called path vectors, and bandwidth is not a default. RIP uses hop count.

What variation of network address translation (NAT) allows multiple inside local addresses to share a single inside global address? A SNAT B Both DNAT and PAT C DNAT D PAT

Answer D is correct. Port address translation (PAT) allows multiple inside local addresses to share a single inside global address. Sessions are kept separate through the tracking of port numbers associated with each session. Answer A is incorrect. Static NAT (SNAT) statically configures an inside global address assigned to a specific device inside your network. Answer C is incorrect. Dynamic NAT (DNAT) automatically assigns an inside global address from a pool of available addresses.

Which of the following standards specifies a type of coaxial cable typically used for short distance applications, such as carrying composite video between two nearby devices, and has a characteristic impedance of 75 Ohms? A RG-58 B MMF C RG-6 D RG-59 E SMF

Answer D is correct. RG-59 is typically used for short distance applications, such as carrying composite video between two nearby devices. This cable type has loss characteristics such that it is not appropriate for long distance applications. RG-59 cable has a characteristic impedance of 75 Ohms.

Which of the following network appliances acts as a relay for packets traveling between a network's clients and the Internet and is not focused on tunneling? A Content switch B VPN concentrator C Load balancer D Proxy server

Answer D is correct. Some clients are configured to forward their packets, which are seemingly destined for the Internet, to a proxy server. This proxy server receives a client's request, and on behalf of that client (that is, as that client's proxy), the proxy server sends the request out to the Internet. When a reply is received from the Internet, the proxy server forwards the response on to the client. Proxy servers can also act as a content filter. Content filtering restricts clients from accessing certain URLs. For example, many companies use content filtering to prevent their employees from accessing popular social networking sites, in an attempt to prevent a loss of productivity.

What loop-prevention mechanism is an override of another loop-prevention mechanism? A Hold down B Split horizon C Poisoning D Poison reverse

Answer D is correct. Split horizon prevents a route from being advertised out an interface from which the route was learned. Poison reverse violates this rule to propagate a poisoned route. Route poisoning and hold down are other loop-prevention mechanisms.

What variation of network address translation (NAT) allows you to statically configure the inside global address assigned to a specific device inside your network? A PAT B DNAT C Both DNAT and PAT D SNAT

Answer D is correct. Static NAT (SNAT) statically configures an inside global address assigned to a specific device inside your network. Answer B is incorrect. Dynamic NAT (DNAT) automatically assigns an inside global address from a pool of available addresses. Answer A is incorrect. Port address translation (PAT) allows multiple inside local addresses to share a single inside global address. Sessions are kept separate through the tracking of port numbers associated with each session.

What is the subnet mask address used in a default static route? A 255.255.255.255 B 1.1.1.1 C 192.168.1.1 D 0.0.0.0

Answer D is correct. The address used for a default static route is 0.0.0.0. The subnet mask is also specified as 0.0.0.0. All other subnet masks and IP addresses shown here would not be valid for the creation of the default static.

What device in an STP domain features all ports in a Designated state? . A Designated bridge B Alternate bridge C Gateway bridge D Root bridge

Answer D is correct. The root bridge is the root of the spanning-tree domain. All of its ports are forwarding and in the Designated state. All other options here do not exist in STP.

A DHCP reservation involves the exchange of four messages between a DHCP client and a DHCP server. What is the first of these messages? A DHCPREQUEST B DHCPOFFER C DHCPACK D DHCPDISCOVER

Answer D is correct. The steps involved in a DHCP reservation are as follows: Step 1. When a DHCP client initially boots, it has no IP address, default gateway, or other such configuration information. Therefore, the way a DHCP client initially communicates is by sending a broadcast message (that is, a DHCPDISCOVER message to a destination address of 255.255.255.255) in an attempt to discover a DHCP server. Step 2. When a DHCP server receives a DHCPDISCOVER message, it can respond with a unicast DHCPOFFER message. Since the DHCPDISCOVER message is sent as a broadcast, more than one DHCP server might respond to this discover request. However, the client typically selects the server that sent the first DHCPOFFER response received by the client. Step 3. The DHCP client communicates with this selected server by sending a unicast DHCPREQUEST message asking the DHCP server to provide IP configuration parameters. Step 4. Finally, the DHCP server responds to the client with a unicast DHCPACK message. This DHCPACK message contains a collection of IP configuration parameters.

You have a Layer 2 switch. You have left all ports in the default VLAN. You connect five workstations. How many collision domains exist on this switch? A 2 B 1 C 0 D 5

Answer D is correct. There is one collision domain for each device connected. Therefore, there are five collision domains.

Consider the fully-qualified domain name (FQDN) host1.pearsonitcertification.com; what is the top-level domain in the FQDN? A http B host1 C pearsonitcertification D com

Answer D is correct. Top-level domain (TLD) refers to the last portion of a domain name, the part that follows the last "dot" in the name. HTTP refers to the protocol being used, host1 refers to a host at pearsonitcertification.com and pearsonitcertification is a sub-domain beneath the top-level domain of .com.

What IP traffic type should you use if you want to send out a video stream to 23 of the systems in the marketing department? There are 50 total systems in this department. A Directed broadcast B Broadcast C Unicast D Multicast

Answer D is correct. Unicast is excellent for sending packets directly to a single system. Broadcast is suitable for sending a packet to all systems. Multicast is ideal in this situation. You can send packets to just those systems that are interested in receiving the traffic. This is typically a subset of all of the systems.

There is a special range of addresses reserved for systems that cannot obtain an IP address automatically from a DHCP server. These addresses are not routable on the network. What is the value in the first octet for these addresses? A 172 B 10 C 192 D 169

Answer D is correct. Values of 10, 172, and 192 are private but internally routable. A portion of the 169.254.0.0/16 address space is reserved for systems that do not receive an automatic address. These reserved portions of the address space are not routable.

A Cisco router has learned a network via three different routing protocols: OSPF, EIGRP, and RIP. Which route will the router believe (that is, inject into the router's IP routing table)? A RIP B A route entry from each routing protocol will be injected into the router's IP routing table, and the router will load-balance across the three routes. C OSPF D EIGRP

Answer D is correct. When a router learns a route from different routing sources (for example, statically configured, directly connected, or dynamically learned), the routing source with the lowest administrative distance (AD) is injected into the router's IP routing table. EIGRP has an AD of 90. OSPF has an AD of 110, and RIP has an AD of 120. Therefore, the route learned via EIGRP is used by the router.

From the following list, identify two common sources of interference with a wireless LAN (WLAN). A CB radios B Microwave ovens C Wireless microphones D Cordless phones

Answers B and D are correct. Older microwave ovens, which might lack sufficient shielding, can emit relatively high-powered signals in the 2.4 GHz band, resulting in significant interference with WLAN devices operating in the 2.4 GHz band. Several models of cordless phones operate in the 2.4 GHz band and can interfere with WLAN devices. Answer A is incorrect. Citizens Band (CB) radio operates at lower frequencies (near 27 MHz) than WLANs. Answer C is incorrect. Wireless microphones operate at lower frequencies (typically less than 1 GHz) than WLANs.

Which two routing protocols use bandwidth in their calculation of metric by default? A EIGRP B BGP C OSPF D RIP

Answers C and A are correct. OSPF and EIGRP will both use bandwidth in the default metric calculations. Answers B and D are incorrect. BGP uses a variety of options for metric, and bandwidth is not a default. RIP uses hop count.

Which two of the following are DHCP options that a DHCP server can assign to a DHCP client? A BOOTP server B APIPA address C Default gateway D DNS server

Answers D and C are correct. Dynamic Host Configuration Protocol (DHCP) can be used to dynamically assign a variety of IP address parameters to a DHCP client. This eliminates the administrative overhead involved with an administrator having to manually configure the IP address information on that client. Examples of IP addressing parameters (called DHCP options) include: IP address, subnet mask, default gateway, DNS server, and WINS server. A DHCP server would not hand out the IP address of a BOOTP server, because a BOOTP server is the predecessor to DHCP. A client would not need to contact both a BOOTP server and a DHCP server. The Automatic Private IP Addressing (APIPA) feature allows a networked device to self-assign an IP address from the 169.254.0.0/16 network. Therefore, if a DHCP client cannot contact their DHCP server, they can automatically assign themselves an IP address from the APIPA IP address range.

Which two of the following are wireless broadband technologies? A ATM B ISDN C WiMAX D HSPA+

Answers D and C are correct. Worldwide Interoperability for Microwave Access (WiMAX) provides wireless broadband access to fixed locations (as an alternative to technologies such as DSL) and mobile devices. Depending on the WiMAX service provider, WiMAX coverage areas could encompass entire cities or small countries. Like WiMAX, Evolved High-Speed Packet Access (HSPA+) is a technology offering wireless broadband service. The maximum data rate for HSPA+ is 84 Mbps. Asynchronous Transfer Mode (ATM) and Integrated Services Digital Network (ISDN), however, are wired broadband technologies.

Which of the following can often be categorized as an encryption device (that is, a device capable of participating in an encrypted session)? Each correct answer represents a complete solution. Choose all that apply. A VPN concentrator B Hub C Router D Firewall

Answers D, A, and C are correct. Enterprise firewalls, VPN concentrators, and routers are typically capable of participating in an encrypted session, meaning that they can support encryption protocols, such as Advanced Encryption Standard (AES). Answer B is incorrect. An Ethernet hub is a Layer 1 device and does not run any encryption algorithms.

Which of the following are valid DHCP message types used during a DHCP reservation? Each correct answer represents a complete solution. Choose all that apply. A DHCPDISCOVER B DHCPLEASE C DHCPACK D DHCPREQUEST

Answers D, A, and C are correct. The four DHCP messages used during a DHCP reservation are: DHCPDISCOVER, DHCPOFFER, DHCPREQUEST, and DHCPACK. There is no DHCPLEASE message. The steps (and corresponding message types) involved in a DHCP reservation are as follows: Step 1. When a DHCP client initially boots, it has no IP address, default gateway, or other such configuration information. Therefore, the way a DHCP client initially communicates is by sending a broadcast message (that is, a DHCPDISCOVER message to a destination address of 255.255.255.255) in an attempt to discover a DHCP server. Step 2. When a DHCP server receives a DHCPDISCOVER message, it can respond with a unicast DHCPOFFER message. Since the DHCPDISCOVER message is sent as a broadcast, more than one DHCP server might respond to this discover request. However, the client typically selects the server that sent the first DHCPOFFER response received by the client. Step 3. The DHCP client communicates with this selected server by sending a unicast DHCPREQUEST message asking the DHCP server to provide IP configuration parameters. Step 4. Finally, the DHCP server responds to the client with a unicast DHCPACK message. This DHCPACK message contains a collection of IP configuration

Which of the following statements about proxy servers and NAT servers are true? (Choose all correct answers.) A. NAT servers and proxy servers can both provide Internet access to clients running any application. B. NAT servers and proxy servers both use public IP addresses. C. NAT servers and proxy servers both access Internet servers and relay the responses to network clients. D. Both NAT servers and proxy servers cache web data for later use.

B and C. To provide clients with Internet access, a NAT or proxy server must have direct access to the Internet, which requires using a registered, or public, IP address. Both NAT and proxy servers function as the middleman in transactions between the client computers on a private network and Internet servers. The NAT or proxy server transmits the client's service request to the Internet server as though it was its own and, after receiving the reply, relays the response back to the client. Because NAT servers function at the network layer, clients can use any application to access the Internet through the server. Proxy servers, however, operate at the application layer and can provide Internet access only to certain types of client applications. Proxy servers are capable of caching web data for later use because they are application layer devices that read the application layer protocol data in the message packets they receive. NAT servers are network layer processes that forward packets with no knowledge of the application layer information in their contents.

Which of the following statements about in-band management and out-of-band management are true? (Choose all correct answers.) A. Out-of-band management tools do not provide access to the remote system's BIOS or UEFI firmware. B. Out-of-band management tools enable you to reinstall the operating system on a remote computer. C. Telnet, Secure Shell (SSH), and Virtual Network Computing (VNC) are in-band management tools. D. To perform out-of-band management on a device, it must have an IP address.

B and C. Out-of-band management uses a dedicated channel to devices on the network. This means that the device to be managed does not require an IP address. The channel provides access to the BIOS or UEFI firmware and makes it possible to reinstall the operating system on a remote computer. Telnet, SSH, and VNC are not out-of-band management tools.

Which of the following statements about single-mode fiber-optic cable are true? (Choose all correct answers.) A. Single-mode cables use an LED light source, whereas multimode cables use a laser. B. Single-mode cables can span longer distances than multimode cables. C. Single-mode cables have a smaller core filament than multimode cables. D. Single-mode cables have a smaller bend radius than multimode, making them easier to install. E. Single-mode fiber-optic cables require a ground, whereas multimode cables do not.

B and C. Single-mode cables have a smaller core filament and can span longer distances than multimode cables. Single-mode cables also use a laser light source, have a larger bend radius, and do not require a ground.

Ed is trying to troubleshoot a problem with his wired network, and his research has led him to a list of possible network faults. The list is rather old, however, and Ed is wondering if some of the problems are relevant. Which of the following wired network problems no longer occur with modern Gigabit Ethernet switches and network adapters in their default configurations? (Choose all correct answers.) A. BottleneckYour selection is incorrect B. Speed mismatchYour selection is incorrect C. Duplex mismatch D. TX/RX reversal

B and C. The Gigabit Ethernet standards call for switches and network adapters to support autonegotiation by default, which enables devices to communicate and select the best network speed and duplex mode available to them both. Therefore, speed mismatches and duplex mismatches no longer occur unless someone modifies the speed or duplex settings to incompatible values on one or both devices.

Which of the following are reasons contributing to the number of packet drops displayed by an interface monitor? (Choose all correct answers.) A. Resets B. Discards C. Errors D. Overflows

B and C. The packet drops displayed by an interface monitor are caused by errors, such as malformed or unreadable packets, or discards, packets that are dropped because they are destined for another interface. Resets and overflows are not reasons for packet drops.

Ralph is adding new workstations to his wireless network, which uses an access point that is configured to use WPA2 encryption. However, after installing the wireless network adapter on the first workstation, Ralph finds that he cannot see the wireless access point on the Available Networks display. Which of the following could be the problem? (Choose all correct answers.) A. Incorrect passphrase B. Channel overlap C. Incorrect SSID D. Incorrect antenna placement

B and D. Both interference resulting from channel overlap and incorrect antenna placement could render the workstation unable to make contact with the access point. An incorrect passphrase would not be the problem unless Ralph had already seen the access point and attempted to connect to it. An incorrect SSID would be the problem only if Ralph had already attempted to manually enter an SSID.

Ralph is working with an ADSL router that has a switch module containing four Ethernet ports, all of which are assigned to the default VLAN1. Ralph can plug a laptop into one of the router's ports and access the Internet with no problems. Ralph now needs to connect the ADSL router to the company network so that the wireless access points on the network can provide users with Internet access through the ADSL router. However, when Ralph plugs the router into a network switch port in VLAN4, the switch starts generating "Native VLAN mismatch detected" errors every minute. Which of the following steps should be part of the solution Ralph implements to stop the error messages? (Choose all correct answers.) A. Create a VLAN1 on the network switch. B. Create a VLAN4 on the ADSL router's switch module. C. Configure the network switch port connected to the router to use VLAN1. D. Configure the router port connected to the network switch to use VLAN4.

B and D. The solution should call for Ralph to create a VLAN on the ADSL router that matches the VLAN the network switch port is using. Therefore, he should create a VLAN4 on the router and assign a port to it, which will be the port Ralph uses to connect the router to the network switch. There is no need to create a VLAN1 on the network switch, because all switches have a default VLAN called VLAN1. Modifying the VLAN assignments on the network switch is not a good idea, because it might interfere with the existing VLAN strategy in place.

Why is it necessary to use a relay agent to enable a Dynamic Host Configuration Protocol (DHCP) server to assign IP addresses to clients on other networks? (Choose all correct answers.) A. Because DHCP requires a separate license for each subnet B. Because clients cannot initiate an address assignment by contacting DHCP servers on other networks directly C. Because DHCP must use the Transmission Control Protocol (TCP) to communicate with clients D. Because the DHCP address assignment process relies on broadcast transmissions

B and D. DHCP clients cannot contact servers on different networks to initiate an address assignment. Clients locate DHCP servers by transmitting broadcast messages, and broadcasts are limited to the local network. Relay agents forward the broadcast messages to other networks, enabling the server to assign IP addresses to clients on other subnets. DHCP does not require special licenses. DHCP uses User Datagram Protocol (UDP) transmissions, not TCP.

Which of the following United States bodies are capable of imposing international export controls on software products? (Choose all correct answers.) A. The company that created the software B. Department of State C. Department of Commerce D. Department of the Treasury

B, C, and D. The U.S. government controls exports of sensitive software and other technology as a means to maintain national security interests and foreign policy agreements. Three U.S. agencies have the authority to issue export licenses: the Department of State, the Department of Commerce, and the Department of the Treasury. Individual software developers do not have the authority to impose their own export controls.

Which of the following is the device that provides the interface between a local area network (LAN) and a wide area network (WAN)? A. QSFP B. CSU/DSU C. SIP trunk D. IDS/IPS

B. A channel service unit/data service unit (CSU/DSU) is a device that provides a LAN router on a private network with access to a leased line WAN connection. Quad Small Form-Factor Pluggable (QSFP) is a standard for a type of modular transceiver, often used on fiber-optic installations. A Session Initiation Protocol (SIP) trunk provides a connection between the private and public domains of a unified communications network, such as a LAN and the Public Switched Telephone Network (PSTN). An intrusion detection system/intrusion prevention system (IDS/IPS) is a network hardware or software security appliance that detects malicious activity and attempts to block it.

A load balancer is a type of which of the following devices? A. Switch B. Router C. Gateway D. Firewall

B. A load balancer is a type of router that forwards traffic with a single IP address to multiple servers in turn. In most cases, a load balancing router works by processing incoming traffic based on rules set by the administrator. Because a load balancer works with IP addresses, it is a network layer device. Load balancers are not switches, gateways, or firewalls.

Which of the following devices enables administrators of enterprise wireless networks to manage multiple access points from a central location? A. Hypervisor B. Wireless controller C. Wireless endpoint D. Demarcation point

B. In many enterprise wireless networks, the access points do not run a full operating system and are called thin or lightweight APs. The network also has a device called a wireless controller that performs some of the required tasks and manages the APs. A wireless endpoint is another term for a computer or other device that is a client on the wireless network. Hypervisors and demarcation points have nothing to do with wireless networking. A hypervisor creates and manages virtual machines on a host server, and a demarcation point is the interface between a private network and an outside telecommunications service.

Ralph is working on a new twisted pair network cable installation on which the individual cable runs were not been properly labeled as they were pulled. Ralph now has to trace each of the cable ends in the office area to the correct cable end in the data center and label them correctly. Which of the following tools should Ralph use to locate the correct cable in a bundle of unlabeled cable ends? A. Cable certifier B. Tone generator and locator C. OTDR D. Multimeter

B. Ralph can use a tone generator and locator to locate the correct cable associated with each office connection. By connecting the tone generator to one end of a cable run, he can use the locator to find the other end. A cable certifier identifies a variety of cable performance characteristics, typically including cabling length, signal attenuation, and crosstalk. An optical time delay reflectometer is a device for measuring the lengths and other characteristics of fiber optic cables. A multimeter is a device for measuring the electric current on a copper cable.

Alice receives a call in which a user reports that he is unable to send print jobs to the network-attached workgroup printer near his desk. Which of the following tasks should Alice perform first? A. Reinstall the printer driver on the user's workstation. B. Test network connectivity to the printer using the ping utility. C. Examine the switches to which the user's workstation and the printer are connected. D. Check to see if there are printer firmware upgrades available

B. The first phase of the troubleshooting process is gathering information. Learning whether the printer is accessible over the network can help Alice to isolate the location of the problem and develop a theory of probable cause. Installing drivers, checking switches, and upgrading firmware are all part of a later phase in the troubleshooting process: testing a theory to determine the cause of the problem

It is Ralph's first day working for a consultancy that does network cable installations. His new boss hands him a spool of Category 6 cable, a large plier-like device, and a bag of little clear plastic components and tells him to "get started on fives and tens." What is Ralph expected to do? A. Pull cable runs B. Create patch cables C. Attach keystone connectors D. Install a patch panel

B. The plier-like device is a crimper, which cable installers use to attach RJ45 connectors, like those in the bag, to lengths of bulk cable. This is the process of creating patch cables, which are used to connect computers to wall plates and patch panels to switches. The boss is telling Ralph to start making patch cables in five and ten foot lengths. You do not use a crimper to attach keystone connectors, and the boss has not given Ralph the tools and components needed to pull cable runs or install a patch panel.

The entire network at Adatum Corp. is unable to access the Internet. All of the users throughout the network are complaining that their browsers are displaying DNS failure messages. The company does not have an in-house network administrator, so they call Ralph at his consulting firm. Which of the following should be the first question that Ralph asks in his attempt to pinpoint the location of the malfunction? A. What browser are the users running? Your selection is incorrect B. Where is the DNS server located? C. What technology is used to provide access to the Internet? D. What sites are the users attempting to access?

B. The users' browsers are failing to resolve the host names of the requested web sites into IP addresses, which they must do before they can connect to the web servers. By asking where the company's DNS server is located, Ralph can determine if the problem is the DNS server itself or the router that provides access to the Internet. If the DNS server is located on Adatum's company network, then the DNS server could be failing to resolve the website names. However, the DNS server could be located on the Internet service provider's network, in which case the problem might be in the router that provides access to the ISP's network.`

Which of the following technologies enables virtual private network (VPN) clients to connect directly to each other, as well as to the VPN server at the home site? A. VPN concentratorYour selection is incorrect B. DMVPN C. SIP trunk D. MPLS

B. VPN typically enables remote clients to connect to a VPN router at a central site, much like the star topology of a local area network, in which computers are all connected to a central switch. Dynamic multipoint virtual private network (DMVPN) is a technology that creates a mesh topology between the remote VPN sites, enabling the remote sites to connect directly to each other, rather than to the central VPN server. A virtual private network (VPN) concentrator is a type of router that enables multiple client systems to access a network from remote locations. A Session Initiation Protocol (SIP) trunk provides a connection between the private and public domains of a unified communications network. Multiprotocol Label Switching (MPLS) is a data transfer mechanism that assigns labels to individual packets and then routes the packets based on those labels.

Alice is a consultant who has been hired to move a client's old 20-node coaxial Ethernet network to a new location. She disassembles all of the network cabling and other components and packs them for shipping. At the new site, she sets up all of the computers, plugs a T-connector into each network adapter, and connects the cables, running them from one computer to the next to form the bus. When Alice is finished, she starts the computers and tests their network connectivity. She finds that 12 consecutive computers can communicate with each other, and the other 8 can communicate with each other, but the 12 cannot communicate with the 8. She makes sure that all of the connectors are securely tightened, especially the ones on the 12th computer, but the problem persists. Which of the following is the most likely cause of the difficulty? A. Alice has forgotten to terminate the computers at each end of the bus. B. One of the connectors on the 12th computer has a bent pin. C. Alice has forgotten to ground the network. D. The transmit and receive pins are reversed on the 12th computer.

B. A bent pin on one of the twelfth computer's connections would cause a break in the bus, essentially forming two networks that operate independently. The failure to terminate or ground the network would not produce this type of fault. Reversing the transmit and receive pins is not possible on a coaxial connection, due to the architecture of the cable.

Which of the following devices can split a single network into two collision domains while maintaining a single broadcast domain? A. Hub B. Bridge C. Switch D. Router

B. A bridge can split a single network into two collision domains, because it forwards only the packets that are destined for the other side of the bridge. The bridge forwards all broadcast packets, so it maintains a single broadcast domain. A hub maintains a single collision domain and a single broadcast domain. A switch creates a separate collision domain for each port, and a single broadcast domain for the entire network. A router creates two collision domains, but it does not forward broadcasts, so there are two broadcast domains as well.

Ralph is testing a twisted pair cable run using a tone generator and locator. When he applies the tone generator to a particular pin at one end of the cable, he detects a tone on two pins at the other end. Which of the following faults has Ralph discovered? A. Open B. Short C. Split pair D. Crosstalk

B. A short is when a wire is connected to two or more pins at one end of the cable or when the conductors of two or more wires are touching inside the cable. This would cause a tone applied to a single pin at one end to be heard on multiple pins at the other end. An open circuit would manifest as a failure to detect a tone on a wire, indicating that there is either a break in the wire somewhere inside the cable or a bad connection with the pin in one or both connectors. A split pair is a connection in which two wires are incorrectly mapped in exactly the same way on both ends of the cable. Crosstalk is a type of interference caused by signals on one wire bleeding over to other wires.

Which of the following is another term for a multiport bridge? A. Router B. Switch C. Hub D. Gateway

B. A switch is a data link layer device that essentially performs the function of a bridge for each device connected to one of its ports. It can therefore be described as a multiport bridge. Routers, hubs, and gateways are devices that operate at the network, physical, and application layers, respectively, so they cannot be described as bridges.`

Which of the following is the name for an attack in which an intruder uses a Bluetooth connection to steal information from a wireless device, such as a smart phone? A. Bluedogging B. Bluesnarfing C. Bluesmurfing D. Bluejacking

B. Bluesnarfing is an attack in which an intruder connects to a wireless device using Bluetooth, for the purpose of stealing information. Bluejacking is the process of sending unsolicited messages to a device using Bluetooth. The other options do not exist.

Which of the following statements about bridges and switches is true? A. Bridges and switches are network layer devices that use logical addressing to forward frames. B. Bridges and switches are data link layer devices that use Media Access Control (MAC) addresses to forward frames. C. Bridges and switches build their internal tables based on destination addresses and forward packets based on source addresses. D. Bridges and switches must support the network layer protocol implemented on the local area network (LAN). E. Each port on a bridge or switch defines a separate broadcast domain.

B. Bridges and switches are data link layer devices that forward frames based on the destination MAC address contained in the frame. They operate in promiscuous mode, listening and processing all frames on each segment, and they build forwarding tables with this information. Forwarding tables are built based on source MAC addresses. Bridges are protocol independent; they are not involved with the upper layer protocols being carried on the LAN. Broadcast domains are defined by network layer devices, not data link layer devices.

VLANs create the administrative boundaries on a switched network that are otherwise provided by which of the following devices? A. Hubs B. Routers C. Firewalls D. Bridges

B. Connecting subnets with routers at the network layer maintains the data link layer administrative boundaries that prevent broadcast transmissions from being propagated throughout the entire internetwork. Switching eliminates those data link layer boundaries, and administrators can use VLANs to simulate them. Because hubs propagate all of the traffic they receive out through all of their ports indiscriminately, they create no administrative boundaries. Firewalls are filtering devices that protect networks against malicious traffic. Their functions are not related to VLANs. Switches are essentially multiport bridges that forward incoming traffic only to the device for which it is destined. Therefore, bridges are more closely related to eliminating administrative boundaries than to establishing them.

VLANs create the administrative boundaries on a switched network that are otherwise provided by which of the following devices? A. Hubs B. Routers C. Domains D. Bridges

B. Connecting subnets with routers at the network layer maintains the data link layer administrative boundaries that prevent broadcast transmissions from being propagated throughout the entire internetwork. Switching eliminates those data link layer boundaries, and administrators can use virtual local area networks (VLANs) to simulate them. Because hubs propagate all of the traffic they receive out through all of their ports indiscriminately, they create no administrative boundaries. Domains are logical groups of network devices defined by the Domain Name System (DNS). Their functions are not related to VLANs in any way. Switches are essentially multiport bridges that forward incoming traffic only to the device for which it is destined. Therefore, bridges are more closely related to eliminating administrative boundaries than to establishing them.

Which of the following terms describes the process by which a client user or computer requests that it be issued a certificate, either manually or automatically? A. Authorization B. Enrollment C. Authentication D. Certification

B. Enrollment is the process by which a client submits a request for a certificate from a certification authority (CA). The enrollment process can be automated and invisible to the user, or it can be a manual request generated using an application. Authorization and authentication, and certification are not terms used for certificate requests.

Ed has been hired by a private company to connect two remote sites with a wide area network (WAN). Each of these sites has more than 200 users, and they all need to constantly transfer files across the WAN. One of the sites has a customer database that is accessed by both sites at all hours of the day. Access to the database and other information is time sensitive and constant. The company estimates that their aggregate bandwidth needs to be approximately 40 Mbps. Management says that they need to guarantee access to this information and that money is not a factor in the WAN implementation. Which WAN technology should Ed recommend for this scenario? A. A standard modem-to-modem connection B. A T-3 dedicated leased line C. An ISDN (Integrated Services Digital Network) Primary Rate Interface (PRI) connection D. An ADSL (Asymmetrical Digital Subscriber Line) connection

B. For this scenario, the best solution is a dedicated leased line connection. This is because the bandwidth requirements are constant and the data transfer rates are high. To support the 40 Mbps data rate, Ed should recommend a T-3 dedicated leased line, running at 44.735 Mbps. Standard modem connections, ADSL, and an ISDN PRI connection are all too slow.

Which of the following types of patches are IT personnel least likely to install unless there is a specific reason to do so? A. Feature change B. Driver update C. Operating system update D. Vulnerability patch

B. If a device driver is functioning properly, many administrators would prefer not to update it, believing that "if it ain't broke, don't fix it." Unless a device driver update addresses a specific bug or an incompatibility that the system is experiencing, there might be no need to install it. Feature changes, operating system updates, and especially vulnerability patches are more likely to be recommended installs.

In which of the following cloud models does a single organization function as both the provider and the consumer of all cloud services? A. Public cloud B. Private cloud C. Hybrid cloud D. Ad hoc cloud

B. In a private cloud, the same organization that utilizes the cloud services is also the sole owner of the infrastructure that provides those services. In the public cloud model, one organization functions as the provider, and another organization consumes the services of the provider. A hybrid cloud is a combination of public and private infrastructure so that the consumer organization is only a partial owner of the infrastructure. There is no such thing as an ad hoc cloud model.

Which of the following command-line utilities is capable of performing the same basic function as traceroute or tracert? Image A. ping B. pathping C. netstat D. route

B. Like traceroute and tracert, pathping is capable of generating a list of the routers that packets pass through on the way to a specific destination system. pathping also displays the percentage of lost packets for each hop, which traceroute and tracert cannot do. The ping, netstat, and route utilities are not capable of displaying route traces.

Which of the following statements about network maps is true? A. Network maps are typically drawn to scale. B. Network maps typically contain more information than network diagrams. C. Network maps must be read/write accessible to all personnel working on the network. D. Network maps diagram only the locations of cable runs and endpoints.

B. Network diagrams typically specify device types and connections, but network maps can also include IP addresses, link speeds, and other information. Network maps diagram the relationships between devices, and provide information about the links that connect them, but they are not drawn to scale and usually do not indicate the exact location of each device. Although universal accessibility would be desirable, there are individuals who should not have access to network maps and other documentation, including temporary employees and computer users not involved in IT work. A network maps include all networking devices, not just cable runs and endpoints.

Q. 172 Ralph recently bought an old Ethernet hub and some twisted pair cables at a garage sale and wants to use them to build a home network. He plugs two computers into the hub using the cables but finds that the computers are unable to communicate. Then he notices that one of the ports in the hub is labeled with an X. He tries plugging one of the computers into the X port, and now they can communicate. Which of the following statements is the most likely explanation for this behavior? A. The hub has a bad port. B. One of the cables is a crossover cable. C. Both of the cables are crossover cables. D. The X port provides extra strength to the signals.

B. Older Ethernet hubs do not autonegotiate crossovers. Instead, they have an X (or uplink) port that provides a connection without a crossover circuit, so you can connect one hub to another. If both of the cables had been standard straight-through Ethernet cables or if both had been crossover cables, then plugging them into two regular ports should have worked. Because plugging one cable into the X port worked, this means that only one of the cables must be a crossover cable. The problem, therefore, was the cable, not the port. The X port does not provide extra strength to the signals.

Which of the following are valid reasons why online uninterruptible power supplies (UPSs) are more expensive than standby UPSs? A. Online UPSs enable devices to run longer when a main power failure occurs.Your selection is incorrect B. Online UPSs enable devices to run continuously when a main power failure occurs. C. Online UPSs are managed devices that can generate alerts. D. Online UPSs provide greater protection against power spikes and sags.

B. Online UPSs run devices from the battery all the time, while simultaneously keeping the battery charged. There is therefore no switchover gap when a power failure occurs. Online UPSs do not necessarily run longer than standby UPSs, nor do they provide more protection again power spikes and sags. Both online and standby UPSs can be managed devices.

You have finished capturing traffic with a protocol analyzer. The analyzer reports that 2000 frames have been seen, but only 1500 frames have been accepted. What does this mean? A. 2000 frames have passed the display filter, but only 1500 meet the criteria for display. B. Only 1500 frames have passed the capture filter and are currently being held in the buffer. C. You lost 500 frames and need to start over—something is obviously wrong. D. 500 frames were damaged and never made it into the buffer.

B. Protocol analyzers report the total number of frames seen compared to the number of frames that were accepted. If a capture filter has been configured, there will be a discrepancy between these two values. Only frames that meet the capture criteria will be accepted by the analyzer and placed in the buffer for later display. Protocol analyzers place good and bad frames into the buffer as long as they meet the capture criteria. If only good frames were placed in the buffer, there would be no way to identify problems.

Which of the following parameters causes the ping tool to transmit messages continually until manually halted? A. -n B. -t C. -i D. -a

B. Running the ping tool with the -t parameter causes it to send messages to the target continuously until you manually stop it. The -n parameter enables you to specify the number of messages the ping tool should transmit. The -i parameter enables you to specify the time-to-live (TTL) value of the messages ping transmits. The -a parameter resolves an IP address you specify as the target to a hostname.

Which of the following Windows commands enables you to delete the entire ARP cache? A. arp -c * B. arp -d * C. arp -a D. arp -s

B. The arp -d command is for deleting cache entries, and by running it with the asterisk wildcard, the command deletes all of the entries in the cache. The arp -a command displays the entries in the ARP table stored in its cache, and the arp -s command is for adding entries. The arp -c * command is not a valid option.

Which of the following command-line utilities can only run on Windows systems? A. ping B. ipconfig C. traceroute D. ifconfig E. netstat

B. The ipconfig command runs only on Windows, although there is a similar Unix/Linux-only command called ifconfig. The ping and netstat utilities run on both Windows and Unix/Linux systems. The traceroute utility runs only on Unix/Linux systems, although there is a Windows version called tracert.

At which layer of the Open Systems Interconnection (OSI) model is there a protocol that adds both a header and footer to the information that is passed down from an upper layer, thus creating a frame? A. Physical B. Data link C. Network D. Transport E. Session F. Presentation G. Application

B. The only layer with a protocol (such as Ethernet) that adds both a header and a footer is the data link layer. The process of adding the headers and footers is known as data encapsulation. All other protocol layers that encapsulate data add just a header.

Q. 145 Which of the following terms defines how long it will take to restore a server from backups if a complete system failure occurs? A. RPO B. RTO C. BCP D. MIB

B. The recovery time objective (RTO) specifies the amount of time needed to restore a server from the most recent backup if it should fail. This time interval depends on the amount of data involved and the speed of the backup medium. A recovery point objective (RPO) specifies how much data is likely to be lost if a restore from backups should be necessary. This figure is based on the frequency of the backups and the amount of new data generated by the system. Business contingency planning (BCP) is an umbrella term for procedures enacted to keep the organization functioning in the event of a disaster. A management information base (MIB) is a database used by Simple Network Management Protocol (SNMP) systems.

Which of the following best explains how tagging the native VLAN traffic can improve in-band switch management security? A. By renaming the default VLAN B. By preventing double-tagged packets C. By encrypting in-band management traffic D. By moving in-band management traffic off the native VLAN

B. When in-band switch management traffic, such as that generated by a Secure Shell (SSH) connection to a switch, uses the native VLAN, it is untagged by default. This is because the native VLAN is at first the default VLAN1, which is not tagged by the 802.1q protocol, leaving it open to certain types of double-tagging attacks. When you tag the native VLAN traffic, it is rendered immune to double-tagging. The default VLAN cannot be renamed, and SSH traffic is already encrypted by the sending workstation. Changing the native VLAN does not move the management traffic off that VLAN, although many authorities advocate the creation of a separate VLAN dedicated to in-band management traffic.

Which of the following statements explains why web browsing over a client-to-site virtual private network (VPN) connection is usually so much slower than browsing locally? A. The browser application is running on the VPN server. B. The browser is using the remote network's Internet connection. C. The VPN tunnel restricts the amount of bandwidth available. D. VPN encryption is processor intensive.

B. When you connect to a remote network using VPN, you become a participant on that network, which includes using the remote network's Internet connection. Therefore, when you open a browser, the application passes your requests through the VPN tunnel to the remote server, which uses the default gateway and Internet connection at the remote site to connect you. This is inherently slower than connecting the browser directly to the Internet from your client computer.

TKIP-RC4 is an encryption protocol used with which of the following wireless network security standards? A. WEP B. WPA C. WPA2 D. EAP

B. Wi-Fi Protected Access (WPA) was created to replace the insecure Wired Equivalent Privacy (WEP) protocol and used the Temporal Key Integrity Protocol (TKIP) with the RC4 cipher. WPA was replaced by WPA2, which uses Counter Mode with Cipher Block Chaining Message Authentication Code Protocol (CCMP) with Advanced Encryption Standard (AES) for encryption. Extensible Authentication Protocol (EAP) is a framework for the encapsulation of authentication messages.

Which of the following wireless network security protocols provides open and shared key authentication options? A. WPA B. WEP C. WPA2 D. EAP

B. Wired Equivalent Privacy (WEP), which was one of the first commercially successful security protocols for wireless LANs, enabled administrators to choose between open and shared key authentication. The open option enabled clients to connect to the network with an incorrect key. The shared option required the correct key, but it also exposed the key to potential intruders. The correct option is not to use WEP at all, as it was easily penetrated and subsequently replaced by Wi-Fi Protected Access (WPA) and then WPA2. Extensible Authentication Protocol (EAP) is a framework for the encapsulation of authentication messages. None of the other three provides a choice between open and shared key options.

If you have a network address of 192.168.1.32/27, what is the valid range of host addresses you can use for your workstations? A. 192.168.1.33 through 192.168.1.63 B. 192.168.1.33 through 192.168.1.62 C. 192.168.1.34 through 192.168.1.62 D. 192.168.1.34 through 192.168.1.63

B. With a network address of 192.168.1.32 and 27 mask bits, the subnet mask value is 11111111.11111111.11111111.11100000 in binary form, or 255.255.255.224 in decimal form. This leaves 5 bits for the host identifier. The valid range of host bits is therefore 00001 (1) through 11110 (30). This gives you a range of 192.168.1.32 + 1 (33) through 192.168.1.32 + 30 (62).

A user calls the company's IT help desk to report that she has received an error message on her Windows workstation. The error states that her computer has an IP address that is duplicated on the network. Ralph is concerned that there might be a configuration problem with the DHCP servers on the network. He suspects that there are DHCP servers configured with scopes that overlap, resulting in two DHCP servers assigning the same IP addresses to different clients. He is worried that they are about to receive a flood of calls reporting the same problem. Alice reassures Ralph, telling him that it cannot be a DHCP problem and that there must be two computers that are manually configured with the same IP address. How does Alice know this?

Because DHCP clients use ARP broadcasts to check for duplicate IP addresses. When a Dynamic Host Configuration Protocol (DHCP) client is offered an IP address by a DHCP server, the client broadcasts Address Resolution Protocol (ARP) requests using that address before accepting it. If another computer on the local network is using the offered address, the computer responds to the ARP request and the DHCP client declines the address. The DHCP server then offers another address. DNS queries and routing table checks are not reliable means of checking for duplicate IP addresses. It is possible to have two DHCP servers on the same local network, but they must be configured with scopes that do not overlap.

Which of the following are Layer 3 redundancy mechanisms? Each correct answer represents a complete solution. Choose all that apply. A LFI B DSCP C HSRP D CARP

C HSRP D CARP Both Hot Standby Router Protocol (HSRP) and Common Address Redundancy Protocol (CARP) provide Layer 3 redundancy. They do so by allowing more than one router (or multilayer switch) to act as a default gateway for a subnet.

Alice is the network administrator of her company's network. The company has just moved into a building that has existing Category 6 (CAT6) unshielded twisted pair cabling. However, none of the cable connections has been labeled, and Alice is trying to identify and document where each cable run starts and ends. Which tools can Alice use for this purpose? (Choose all correct answers.) A. A packet sniffer B. A loopback connector C. A tone generator and locator D. A wiremap tester

C and D. Alice can use a tone generator and locator or a wiremap tester to identify and test cable connections. By connecting the tone generator and or the remote wiremap unit to one end of a cable run, she can use the locator or the master wiremap unit to find the other end. This can enables her to identify a starting point and an ending point for a cable run. A loopback connector is used to test the transmission and reception capabilities of a port. A packet sniffer captures and analyzes network traffic; it cannot identify cables.

Which of the following physical network devices can conceivably be implemented as software in a computer's operating system? (Choose all correct answers.) A. Hub B. SwitchYour selection is incorrect C. Router D. Firewall

C,D Most operating systems are capable of functioning as routers or firewalls. To route traffic, the system must have two network connections. A software firewall can be part of a computer's routing functionality, or it can be a stand-alone firewall that protects only the local system. Computers cannot function as hubs or switches because multiple ports would be required and standard network adapters don't implement those functions.

Account lockout policies are designed to protect against which of the following types of attacks? A. Social engineering B. Spoofing C. Brute force D. Man in the middle

C. A brute-force password attack is one in which the perpetrator tries as many passwords as possible in an effort to guess or deduce the right one. Account lockout policies are intended to prevent this type of attack by limiting the number of incorrect password attempts.

Which of the following statements about content filtering is true? A. Content filters examine the source IP addresses of packets to locate potential threats. B. Content filters enable switches to direct packets out through the correct port. C. Content filters examine the data carried within packets for potentially objectionable materials. D. Content filters use frequently updated signatures to locate packets containing malware.

C. Content filters are a firewall feature that examines the data inside packets, rather than their origin, to locate objectionable material such as pornography. They do not scan IP addresses, nor do they detect typical types of malware. Content filters are not implemented in switches.

A user, Ed, is reporting what appear to be intermittent traffic interruptions on his workstation. Sometimes he receives responses to his server requests, and sometimes not. It doesn't seem to be an Internet issue, because the problem also occurs with local server requests. While troubleshooting the problem, Ralph performs a series of packet captures and analyzes the network traffic. He discovers that all of the request messages generated by Ed's workstation have responses on the network, but in some cases, the responses are going to a workstation other than Ed's. Which of the following conditions could be causing this to happen? A. Duplicate IP addresses B. Blocked TCP/UDP ports C. Duplicate MAC addresses D. Incorrect host firewall settings

C. If someone on the network is spoofing the MAC address of Ed's workstation, the MAC address table in the switch handing the network traffic might be continually changing as packets from each computer reach the switch. This could cause some of the response packets to be forwarded to Ed's workstation and some to the spoofer's workstation. Duplicate IP addresses would not cause this problem because they would be detected by the operating system. Blocked ports and incorrect firewall settings could prevent Ed from receiving responses, but they would not be sent to another workstation.

Which of the following is not a function that is typically provided by unified threat management (UTM) appliance? A. Virtual private networking B. Network firewall C. Packet forwarding D. Antivirus protection

C. Packet forwarding is a function typically associated with routers and is not a normal function of a UTM appliance. UTM appliances do typically perform VPN, firewall, and antivirus functions.

Alice has recently created a new perimeter network for the company's web server cluster, along with a router to connect it to the internal network. When she is finished, she sends Ralph an email instructing him to run the following command on his Windows workstation so that he can access the servers on the perimeter network. What function does the IP address 192.168.87.226 perform in this command? route add 192.168.46.0 MASK 255.255.255.0 192.168.87.226 A. 192.168.87.226 is the address of Ralph's workstation. B. 192.168.87.226 is the network address of the perimeter network. C. 192.168.87.226 is the address of one of the router's interfaces. D. 192.168.87.226 is the address of web server cluster

C. The correct syntax for the Windows route add command is to specify the destination network address, followed by the subnet mask for the destination network, followed by the address of the router interface on the local network that provides access to the destination network. Therefore, 192.168.87.226 is the address of the router interface on the internal network, where Ralph's workstation is located

In telecommunications, the term broadband has had a variety of definitions over the years. Which of the following is not one of the standard definitions of the term? A. A medium that connects to the Internet at high speed and is always on B. A medium that carries a wide range of frequencies C. A medium that uses a cable with a relatively large diameter D. A medium that runs at a speed higher than a 56 Kbps modem E. A medium that transmits multiple signals at once

C. The term broadband has nothing to do with the width of the cable. However, the term as been used to refer to a transmission medium that carries multiple signals, that carries a wide range of frequencies, that is faster than a dial-up modem, and that provides an always-on, high-speed connection to the Internet.`

Which of the following Domain Name System (DNS) resource records is used to implement email security mechanisms such as Sender Policy Framework and DomainKey Identified Mail? A. MX B. PTR C. TXT D. CNAME

C. A TXT resource record contains a text string that can be used for various applications. Sender Policy Framework (SPF) inserts a list of authorized email hosts into the TXT record and DomainKey Identified Email (DKIM) inserts a public key. MX, PTR, and CNAME records are not used for SPF and DKIM. A Mail Exchange (MX) record specifies the mail server that the domain should use. Pointer (PTR) records also contain host names and IP addresses, but they are used for reverse name resolution, that is, resolving IP addresses into host names. Canonical name (CNAME) records specify aliases for a given host name.

In a client-to-site virtual private network (VPN) connection, which of the following combinations of endpoint devices would most likely be involved? A. Two workstations B. A workstation and a server C. A workstation and a VPN concentrator D. Two VPN concentrators

C. A client-to-site VPN connection connects a single workstation to a remote local area network (LAN), enabling the workstation user to access the remote network's resources. The typical configuration would consist of a standalone workstation and a VPN concentrator at the network site functioning as the endpoints of the connection.

Upgrading a wireless network from the Wired Equivalent Privacy (WEP) security protocol to Wi-Fi Protected Access (WPA) enables it to use the Temporal Key Integrity Protocol (TKIP) for encryption, which generates a unique key for each packet. Which of the following types of attacks does this capability prevent? A. Denial-of-service attacks B. Brute-force attacks C. Replay attacks D. Deauthentication attacks

C. A replay attack is one in which an attacker utilizes the encryption key found in a previously captured packet to gain access to the network. Because TKIP generates a unique encryption key for every packet, it prevents this type of attack from being successful.

Which of the following types of physical security is most likely to detect an insider threat? A. Smartcards B. Motion detection C. Video surveillance D. Biometrics

C. An insider threat by definition originates with an authorized user. Smartcards, motion detection, and biometrics will only detect the presence of someone who is authorized to enter sensitive areas. Video surveillance, however, can track the activities of anyone, authorized or not.

Which of the following statements best describes the difference between the fault tolerance mechanisms disk mirroring and disk duplexing? A. Disk mirroring enables a server to survive the failure of a disk drive. B. Disk duplexing enables a server to survive the failure of a disk controller. C. Disk duplexing enables a server to survive a failure of a disk drive or a disk controller. D. Disk duplexing enables a server to survive a failure of a disk drive or a disk controller.

C. As with disk mirroring, disk duplexing uses multiple hard disk drives to store duplicate copies of all data. However, disk duplexing calls for each disk to be connected to a separate controller so that the data remains available despite a disk failure or a controller failure.

Which of the following protocols does IPsec use to digitally sign packets before transmitting them over the network? A. ESP B. SSL C. AH D. MSCHAP

C. Authentication Header (AH) is a protocol in the TCP/IP suite that provides digital integrity services, in the form of a digital signature, which ensures that an incoming packet actually originated from its stated source. Encapsulating Security Protocol (ESP) provides encryption services for IPsec. Secure Sockets Layer (SSL) is a security protocol that provides encrypted communications between web browsers and servers. MSCHAP is an authentication protocol used by remote access services.

Which of the following terms refers to the process of determining whether a user is a member of a group that provides access to a particular network resource? A. Authentication B. Accounting C. Authorization D. Access control

C. Authorization is the process of determining what resources a user can access on a network. Typically, this is done by assessing the user's group memberships. Authentication is the process of confirming a user's identity. Accounting is the process of tracking a user's network activity. Access control is the creation of permissions that provide users and groups with specific types of access to a resource.

Ed is working the help desk at a local computer store, and he receives a call from a customer trying to set up a home network using Windows 10 and wired Ethernet equipment. The customer reports that, from her computer, she can see the two other computers in the house, but she cannot access the Internet. Ed asks her to run the ipconfig /all command and read the results to him. She says that her IP address is 172.16.41.2, her subnet mask is 255.255.255.0, and her default gateway is 172.16.43.1. Which of the following is most likely the cause of the customer's problem? A. The customer's network cable is unplugged. B. The customer has an incorrect subnet mask. C. The customer has an incorrect default gateway address. D. The computer's DNS record contains the wrong information.

C. Because the customer can access the other two computers in the house, Ed knows that her IP address and subnet mask are properly configured that the network cable is plugged in and functional. Ed also knows that the computer's DNS record does not play a role in outgoing connections. The problem is most likely the default gateway because the gateway address the customer specified is on another network, 172.16.43.0, rather than on her own network, 172.16.41.0.

Why does performing incremental backups to a hard drive, rather than a tape drive, make it possible to restore a server with a single job, rather than multiple jobs? A. Because hard drives hold more data than tape drives B. Because hard drives can transfer data faster than tape drives C. Because hard drives are random access devices and tape drives are notYour selection is incorrect D. Because hard drives use a different block size than tape drives

C. Data is stored on tape drives in a linear fashion. Once you write backup data to a tape, you cannot selectively replace individual files. When you perform a restore job, you might have to restore the most recent full backup, followed by incremental backups, which overwrite some of the full backup files with newer ones. Hard disk drives are random access devices, meaning that individual files can be written to and read from any location on the disk. When you perform incremental backup jobs to a hard disk, the software can restore data using any version of each file that is available. Data capacity, transfer speed, and block size are not relevant.

Which of the following is not one of the typical heights for devices mounted in IT equipment racks? A. 1 unit B. 2 units C. 3 units D. 4 units

C. Devices designed to fit into IT equipment racks typically have heights measured in units. One unit equals 1.75 inches. Most rack-mounted devices are one (1U), two (2U), or four units (4U) tall.

Which of the following backup job types does not reset the archive bits of the files it backs up? A. Full B. Incremental C. Differential D. Supplemental

C. Differential backups use the archive bit to determine which target files to back up. However, a differential backup does not reset the archive bit. Full backups do not pay attention to the archive bit because they back up all of the files. A full backup, however, does clear the archive bit after the job is completed. Incremental backups also use the archive bit to determine which files have changed since the previous backup job. The primary difference between an incremental and a differential job, however, is that incremental backups clear the archive bit so that unchanged files are not backed up. There is no such thing as a supplemental backup job.

Which of the following virtual private networking (VPN) protocols does not provide encryption within the tunnel? A. PPTP B. IPsec C. L2TP D. SSL

C. Layer 2 Tunneling Protocol (L2TP) is used to create the tunnel forming a VPN connection, but it does not encrypt the traffic passing through the tunnel. To do this, it requires a separate protocol that provides encryption, such as IPsec. Point-to-Point Tunneling Protocol (PPTP) and Secure Sockets Layer (SSL) are both capable of encrypting tunneled traffic.

At what point in the installation process should patch panel ports and wall plates be labeled? A. When the patch panels and wall plates are installed B. When a length of cable is cut from the spool C. When the cables are attached to the connectors D. When the cable runs are tested, immediately after their installation

C. Patch panel ports and wall plates should be labeled when the cable runs are attached to them. Labeling them at any earlier time can result in cable runs being connected incorrectly.

Which of the following virtual private networking protocols is generally considered to be obsolete? A. IPsec B. L2TP C. PPTP D. SSL/TLS

C. Point-to-Point Tunneling Protocol (PPTP) is considered to be obsolete for VPN use because of several serious security vulnerabilities that have been found in it. IPsec, Layer 2 Tunneling Protocol (L2TP), and Secure Sockets Layer/Transport Layer Security (SSL/TLS) are all still in use.

Which of the following Redundant Array of Independent Disks (RAID) levels provides fault tolerance by storing parity information on the disks, in addition to the data? (Choose all correct answers.) A. RAID 0 B. RAID 1 C. RAID 5 D. RAID 10

C. Redundant Array of Independent Disks (RAID) is a technology for storing data on multiple hard disk drives, providing fault tolerance, increased performance, or both. The various RAID levels provide different levels of functionality and have different hardware requirements. RAID 5 combines disk striping with distributed storage of parity information, which provides fault tolerance. The parity information enables the array to rebuild a disk whose data has been lost. RAID 0 uses data striping only (blocks written to each disk in turn), which does not provide any form of fault tolerance. RAID 1 provides fault tolerance through disk mirroring. RAID 10 creates fault-tolerant mirrored stripe sets.

Which of the following parameters enables you to specify the time-to-live (TTL) value of the messages ping transmits? A. -n B. -t C. -i D. -a

C. Running the ping tool with the -i parameter enables you to specify the time-to-live (TTL) value of the messages ping transmits. The -t parameter causes the ping tool to send messages to the target continuously until you manually stop it. The -n parameter enables you to specify the number of messages the ping tool should transmit. The -a parameter resolves an IP address you specify as the target to a hostname.

Which IP address allocation method is not supported by Dynamic Host Configuration Protocol (DHCP)? A. Manual B. Dynamic C. Stable D. Automatic

C. Stable is not a DHCP allocation method. DHCP supports three allocation methods: manual, dynamic, and automatic.

What is the name for a device that determines the length of a cable by transmitting a signal at one end and measuring how long it takes for a reflection of the signal to return from the other end? A. Fox and hound tester B. Wiremap tester C. Time domain reflectometer D. Voltage event recorder E. Butt set

C. The technique that provides this capability is called time domain reflectometry (TDR). The tester transmits a signal over the cable and measures how long it takes for a reflection of the signal to return from the other end. Using this information and the cable's nominal velocity of propagation (NVP)—a specification supplied by the cable manufacturer—the device can calculate the length of a cable run.

Alice has been assigned the network address 172.21.0.0/22 for the creation of a new department network in her company. How many host addresses does she have available to her? A. 510 B. 512 C. 1022 D. 1024

C. To calculate the number of host addresses available, Alice must determine the number of host bits in the address, which is 10, raise 2 to that power, and subtract 2 for the network and broadcast addresses, which are unusable for hosts. The formula is therefore 2x-2. 210-2=1022.

The protocols at which layer of the Open Systems Interconnection (OSI) model use port numbers to identify the applications that are the source and the destination of the data in the packets? A. Application B. Presentation C. Transport D. Network

C. Transport layer protocols, such as Transmission Control Protocol (TCP) and User Datagram Protocol (UDP), have header fields that contain the port numbers of the applications that generated the data in the packet and that will receive it. The application, presentation, and network layers do not use port numbers.

Which of the following terms describes a connectivity problem on wired networks that is caused by individual packets that are delayed due to network congestion, different routing, or queuing problems? A. Latency B. Attenuation C. Jitter D. Bottleneck

C. When individual packets in a data stream are delayed, the resulting connectivity problem is called jitter. Although this condition might not cause problems for asynchronous applications, real-time communications, such as Voice over IP or streaming video, can suffer interruptions, from which the phenomenon gets its name. Latency describes a generalized delay in network transmissions, not individual packet delays. Attenuation is the weakening of a signal as it travels through a network medium. A bottleneck is a condition in which all traffic is delayed, due to a faulty or inadequate component.

Which of the following wireless security protocols can enable network users to authenticate using smartcards? A. WEP B. WPA2 C. EAP D. AES

C. Wired Equivalent Protocol (WEP) and Wi-Fi Protected Access II (WPA2) are both wireless security protocols that control access to the network and provide encryption, using protocols like Advanced Encryption Standard (AES). These protocols do not provide authentication services, however. Extensible Authentication Protocol (EAP) is a framework for the encapsulation of authentication messages. Its many variants provide support for the use of smartcards and other authentication factors, such as biometrics, in addition to traditional passwords.

Ralph is performing a site survey for a wireless LAN installation in a warehouse with two offices at either end of the building, approximately 300 feet apart. If he installs a single access point in the center of the warehouse, equidistant from the two offices, which of the following standards should he look for when purchasing hardware so that workstations in both offices will be able to connect to the network at the best possible speed? A. IEEE 802.11a B. IEEE 802.11g C. IEEE 802.11n D. IEEE 802.11ac

C. Wireless networks using equipment based on the IEEE 802.11n standard can span indoor distances of up to 175 feet at speeds up to 600 Mbps. An 802.11ac network can run at faster speeds—up to 1.3 Gbps—but it is limited to approximately 115-foot distances. Networks using 802.11g equipment can span 150 feet, but they run at only a maximum of 54 Mbps. An 802.11a network cannot span more than 75 feet, and it runs at no more than 54 Mbps.

Which of the following twisted pair cable types can you use to construct a 10GBase-T network with 100-meter segments? (Choose all correct answers.) A. CAT5 B. CAT5e C. CAT6 D. CAT6a E. CAT7

D and E. Category 6a (CAT6a) twisted pair cable is a variant on CAT6 that enables you to create 10GBase-T networks with segments up to 100 meters long. Category 7 (CAT7) cable adds shielding both to the individual wire pairs and to the entire cable, for even greater resistance to crosstalk and noise. CAT7 supports 100-meter 10GBase-T segments as well. CAT5 and CAT5e are not suitable for use with 10GBase-T. You can use CAT6 for 10GBase-T, but it is limited to 55-meter segments.

Which of the following message types are exchanged by Dynamic Host Configuration Protocol (DHCP) clients and servers during a successful IP address lease renewal transaction? (Choose all correct answers.) A. DHCPDISCOVER B. DHCPOFFER C. DHCPINFORM D. DHCPACK E. DHCPREQUEST F. DHCPNAK G. DHCPRENEW H. DHCPRELEASE

D and E. In a successful DHCP address renewal transaction, the client issues a DHCPDREQUEST message, and the server replies with a DHCPACK. DHCPNAK messages are only used in unsuccessful transactions, and the other message types are not used during the address renewal process.

Which of the following wide area network (WAN) technologies is considered to be both a packet-switched and a circuit-switched service? A. PSTN B. T-1 leased line C. Metropolitan Ethernet D. ATM

D. Asynchronous Transfer Mode (ATM) is a cell-switched protocol that is designed to carry voice, data, and video traffic by splitting it into uniform 53-byte cells. To this degree, it can be considered a packet-switched service. However, it is unlike traditional packet-switched protocols, which use variable-sized packets. ATM can also be called a circuit-switched service, because the end systems must create a virtual circuit before they transfer any data. Public Switched Telephone Network (PSTN) and T-1 leased lines are both circuit-switched network types, while Metropolitan Ethernet is packet-switched.

Which of the following wide area network (WAN) technologies uses broadband signaling? A. Digital Subscriber Line (DSL) B. Synchronous Optical Network (SONET) C. Integrated Services Digital Network (ISDN) D. Cable television (CATV)

D. CATV networks use broadband signaling, which enables many signals to occupy the same channel. DSL and ISDN do not use broadband signaling. SONET is a physical layer standard that defines fiber-optic connections.

Why does DSL (Digital Subscriber Line) technology support faster data transmissions than a standard Public Switched Telephone Network (PSTN) modem connection? A. DSL uses a separate control circuit that provides clear channels for data. B. DSL does not perform cyclical redundancy check (CRC) functions and therefore has less overhead. C. DSL performs only a single analog-to-digital conversion. D. DSL uses a higher frequency range.

D. DSL technology provides higher data rates because it uses frequency ranges that are higher than the standard voice spectrum. DSL connections use from 10 kHz and above, whereas the standard voice spectrum uses 300 Hz to 4 kHz. DSL does not use separate control circuits and does not perform CRC functions. Also, DSL technology is strictly digital and does not require an analog-to-digital conversion.

Which of the following wide area network (WAN) services typically uses a switched fabric that was called a cloud long before the term came into general use? A. ATM B. Fractional T-1 C. SONET D. Frame relay

D. Frame relay is a packet switching service that uses a single leased line to replace multiple leased lines by multiplexing traffic through a cloud. Asynchronous Transfer Mode (ATM) uses a switched fabric, but it is not referred to as a cloud. A fractional T-1 is part of a leased line that connects two points, so there is no switching involved and no cloud. SONET is a physical layer standard that defines fiber-optic connections; it does not call for switching or use the term cloud.

Q. 256 If you want to allow both voice and data traffic to be transmitted across the same Digital Subscriber Line (DSL) connection, what type of device is required at the customer site? A. A signal terminator B. A Digital Subscriber Line Access Multiplexer (DSLAM) C. A coder/decoder (CODEC) device D. A splitter

D. In a DSL connection, a signal splitter is needed at the customer site to separate the lower frequency voice range from the higher frequencies used by data traffic. The higher frequency signals are handled at the central office by a DSLAM device. Lower frequency signals carrying voice traffic are handled at the central office by a CODEC device. A signal terminator is not required by DSL.

A company is moving their entire operation to a new building, and part of the plan is to increase the speed of their Internet access by installing a leased T-3 line to replace their existing broadband connection. The service provider they have selected sends a technician to install the leased line. Which of the following is the correct term for the location in the new building where the technician will terminate the T-3? A. Patch panel B. Switch C. Firewall D. Demarc

D. The demarc, or demarcation point, is the place where a service enters the building, and where the service provider's physical layer responsibility ends. The patch panel, the switch, and the firewall are all inside the network, and they are the responsibility of the subscriber.

Which of the following is a correct definition of a collision domain? A. A group of local area networks (LANs), connected by routers, that enables any node to transmit to any other node B. A group of computers connected so that a broadcast transmission by any one device reaches all of the other devices C. A group of devices connected by cable segments that are longer than the maximum length stated in the physical layer specification D. A group of devices connected so that when two devices transmit at exactly the same time, a data collision occurs

D. A collision domain is a LAN with a shared network medium, so that two devices transmitting at the same time generate a signal quality error, also known as a collision. Ethernet LANs connected by hubs create a shared medium, whereas switched networks create a separate collision domain for each connected node. Routers create separate collision domains. A group of computers able to receive broadcasts is the definition of a broadcast domain, not a collision domain. Overlong cables can precipitate collisions but do not define a collision domain.

Which of the following devices enables two computers to communicate when they are using different protocols at each layer of the Open Systems Interconnection (OSI) reference model? A. A router B. A switch C. A switch D. A gateway

D. A gateway enables two devices using different protocols to communicate by performing translation and conversion services for them. Routers, hubs, and switches all require the same protocol at some of the OSI model layers.

In a site-to-site virtual private network (VPN) connection, which of the following combinations of endpoint devices would most likely be involved? A. Two workstations B. A workstation and a server C. A workstation and a VPN concentrator D. Two VPN concentrators

D. A site-to-site VPN connection connects two remote local area networks (LANs) together, enabling users on either network to access the other one. The typical configuration would consist of two VPN concentrators, one at each site, functioning as the endpoints of the connection.

Which of the following statements about a wired local area network (LAN) is true? A. Wired LANs support only the star topology. B. Wired LANs support only the star and bus topologies. C. Wired LANs support only the star and ring topologies. D. Wired LANs can support ring, bus, or star topologies.

D. A wired LAN is a group of computers within a small area, connected by a common network medium. A wired LAN can be configured using a ring, bus, or star topology.

When you troubleshoot a network problem, it is possible to introduce another problem while attempting to fix the original one. In which step of the troubleshooting process should you be aware of the residual effects that changes might have on the network? A. Identify the problem B. Establish a theory of probable cause C. Test the theory to determine cause D. Establish a plan of action to resolve the problem E. Implement the solution or escalate as necessary F. Verify full system functionality G. Document findings, actions, and outcomes

D. After you identify a problem and establish and test a theory of its probable cause, you must create a plan of action to resolve the problem and identify any potential effects (positive or negative) your solution might have. Then, you implement your solution, test the results, and finish documenting the incident.

Which of the following types of virtual private networking (VPN) connection is the best solution for allowing clients limited access to your corporate network? A. Host-to-site B. Site-to-site C. Host-to-host D. Extranet

D. An extranet VPN is designed to provide clients, vendors, and other outside partners with the ability to connect to your corporate network with limited access. A host-to-site VPN is a remote access solution, enabling users to access the corporate network from home or while traveling. A site-to-site VPN enables a branch office to connect to the home office using the Internet rather a more expensive wide area network (WAN) connection. A host-to-host VPN enables two individual users to establish a protected connection to each other.

For a complete restore of a computer that failed at noon on Tuesday, how many jobs would be needed if you performed full backups to tape at 6:00 a.m. every Wednesday and Saturday and incremental backups to tape at 6:00 a.m. every other day? A. One B. Two C. Three D. Four

D. An incremental backup is a job that backs up all of the files that have changed since the last backup of any kind. Therefore, to restore a system that failed on Tuesday at noon, you would have to restore the most recent full backup from the previous Saturday and the incrementals from Sunday, Monday, and Tuesday morning.

Ed is inspecting the cable runs recently installed for some new Gigabit Ethernet systems on his network. Looking at the patch panel connections, he notices that they are wired using the T568B pinout standard. However, when he examines the wall plate connections, he sees that they are wired using the T568A standard. What is the best way for Ed to resolve the problem? A. Call the contractor and have all of the wall plate connectors rewired using the T568B standard. B. Purchase crossover patch cables for all of the connections between the patch panel and the switches. C. Configure the switches not to use a crossover circuit for all of the ports connected to the patch panel. D. Do nothing. The cable runs will function properly as is.

D. Cable runs are traditionally wired "straight through," that is, with the transmit pins at one end wired to the transmit pins at the other end. It is the switch that is supposed to implement the crossover circuit that connects the transmit pins to the receive pins. Cable runs wired using T568A at one end and T568B at the other end create a crossover circuit in the cable run. At one time, this would have been a serious problem, but today's switches automatically configure crossover circuits as needed, so they will adjust themselves to adapt to the cable runs. All of the other options would correct the problem, but doing nothing is certainly the best option.

87 Which of the following statements about DHCP snooping is not true? A. DHCP snooping detects rogue DHCP servers. B. DHCP snooping is implemented in network switches. C. DHCP snooping drops DHCP messages arriving over the incorrect port. D. DHCP snooping prevents DNS cache poisoning.

D. DHCP snooping is a feature found in some network switches that prevents rogue DHCP servers from assigning IP addresses to clients. It can also detect when DHCP release or decline messages arrive over a port other than the one on which the DHCP transaction originated. Although DHCP snooping can prevent DHCP clients from being assigned an incorrect IP address, it does not directly prevent the poisoning of DNS server caches with erroneous information.

Which of the following is a security protocol that is specifically designed to protect UDP traffic exchanged by web browsers and servers? A. SSL B. TLS C. SSH D. DTLS

D. Datagram Transport Layer Security (DTLS) is a protocol that provides the same encryption and other web server/browser security functions as Transport Layer Security (TLS), but for User Datagram Protocol (UDP) traffic. Secure Sockets Layer (SSL) is the original security protocol for web servers and browsers and the predecessor of TLS. Secure Shell (SSH) is a character-based tool that enables users to execute commands on remote computers. It does not provide web server/browser security.

Which of the following terms refers to a routing protocol that does not rely on hop counts to measure the efficiency of routes? A. Interior gateway protocol B. Edge gateway protocol C. Distance vector protocol D. Link state protocol

D. Distance vector protocols rely on hop counts to evaluate the efficiency of routes. Link state protocols use a different type of calculation, usually based on Dijkstra's algorithm. The terms interior gateway protocol and edge gateway protocol do not refer to the method of calculating routing efficiency.

Which of the following is a PPP authentication protocol that enables users to authenticate using smartcards and fingerprint scanners, as well as usernames and passwords? A. PPTP B. PAP C. CHAP D. EAP

D. Extensible Authentication Protocol (EAP) is a shell protocol used with Point-to-Point Protocol (PPP), which enables systems to support various types of authentication mechanisms. The primary advantage of EAP is that it enables a computer to use mechanisms other than passwords for authentication, including public key certificates, smartcards, and biometric devices, such as fingerprint scanners. Password Authentication Protocol (PAP) and Challenge Handshake Authentication Protocol (CHAP) support only password authentication. Point-to-Point Tunneling Protocol (PPTP) is a virtual private networking (VPN) protocol, not an authentication protocol.

Which of the following is not a protocol operating at the network layer of the OSI model? A. IP B. ICMP C. IGMP D. IMAP

D. Internet Protocol (IP), Internet Control Message Protocol (ICMP), and Internet Group Message Protocol (IGMP) are all network layer protocols. Internet Message Access Protocol (IMAP) is a mail protocol that operates at the application layer.

Which of the following statements about port aggregation is NOT true? A. All of the aggregated ports use the same MAC address. B. Port aggregation can be a fault tolerance mechanism. C. Aggregating ports increases network throughput. D. Port aggregation provides load balancing.

D. Load balancing refers to the distribution of traffic between two or more channels. Port aggregation combines ports into a single logical channel with a single MAC address and provides greater throughput. Port aggregation also provides fault tolerance in the event of a port failure.

When a service fails to start on a Windows server, an entry is typically created in which of the following event logs? A. Application B. Security C. Setup D. System

D. On a Windows system, information about services, including successful service starts and failures, is recorded in the System event log. The Application, Security, and Setup logs typically do not contain this type of information.

Q. 260 Which of the following terms refers to the process of uninstalling a recently released patch to resume using the previous version? A. Backslide B. Downgrade C. Reset D. Rollback

D. Rollback is a term used in change management to describe the process of reversing a change that has been made, to restore the original configuration. In the case of patch management, a rollback is the process of uninstalling a recently installed software update. The terms backslide, downgrade, and reset are not used to describe this procedure.

When the Wi-Fi Protected Access (WPA) wireless security protocol was released to replace Wired Equivalent Privacy (WEP), it included the Temporal Key Integrity Protocol (TKIP) for encryption. Which of the following is not one of the improvements that WPA and TKIP provide over WEP? A. TKIP enlarges the WEP encryption key. B. TKIP modifies the encryption key for every packet. C. WPA does not require a hardware upgrade for WEP devices. D. TKIP eliminates the use of preshared keys.

D. TKIP augments the existing WEP encryption key, making it longer, enabling it to be changed for every packet, and enabling WPA to be deployed without replacing network adapter or access point hardware. TKIP does continue to support the use of preshared keys.

Which of the following physical layer transceiver module standards is the oldest and therefore the most obsolete? A. SFP B. SFP+ C. QSFP D. GBIC

D. The Gigabit Interface Converter (GBIC) transceiver standard was first published in 1995 and defines a maximum data transfer rate of 1.25 Gbps. It was rendered all but obsolete by the Small Form-factor Pluggable (SFP) standard, introduced in 2001, which ran at the same maximum speed but was smaller in size. Subsequent variations on the standard, such as Quad Small Form-Factor Pluggable (QSFP), defined devices with faster transfer rates. Bidirectional (BiDi) transceivers were developed to eliminate the need for separate transmit and receive fibers by using multiplexing.

Which of the following Windows tools uses ICMP messages and manipulates IPv4 time-to-live values to illustrate the route packets take through an internetwork? A. Ping B. Netstat C. Route D. Tracert E. Nslookup

D. The Windows tracert tool transmits a series of ICMP messages with incrementing time-to-live (TTL) values, which identify each router on the path the packets take through the network. ping uses ICMP, but it does not manipulate TTL values. netstat, route, and nslookup do not use ICMP messages, nor do they manipulate TTL values when performing their normal functions.

Ralph is responsible for the network installation in a new building purchased by his company, and he has elected to have Category 6 unshielded twisted pair cable installed. The company president has asked him if it is possible to run their Gigabit Ethernet network using two of the wire pairs in the cable, while using the other two pairs for telephone connections. Ralph is not sure, so he sets up a lab network using cables with only two pairs connected. When he plugs computers into the switch and turns them on, the LEDs labeled 1000 light up, indicating that a Gigabit Ethernet connection has been established. Ralph gets excited at the thought of how much money he might save the company by using the same cable for both telephone and data. However, while the LED is lit, he can't seem to connect to another system over his test network. Which of the following describes what he must do to correct the problem? A. Ralph must manually configure the network adapters to use Gigabit Ethernet, rather than let them autonegotiate. B. Ralph is using the wrong two wire pairs for the Gigabit Ethernet connection. He must rewire the connectors. C. Ralph is using the wrong pinout standard on his lab network. He must use T568A. D. Ralph must use all four wire pairs for a Gigabit Ethernet connection.

D. The autonegotiation mechanism is not the problem, nor is the pinout standard or Ralph's wire pair selection. The speed autonegotiation mechanism in Gigabit Ethernet uses only two wire pairs, so although the LEDs do light up successfully, a functional Gigabit Ethernet data connection requires all four wire pairs.

What is the term used to refer to the DNS client mechanism that generates name resolution queries and sends them to DNS servers? A. Requestor B. Forwarder C. Authority D. Resolver

D. The client component of the Domain Name System is called the resolver. Requestor is a generic term for any system issuing requests, and only DNS servers can be authorities or forwarders.

The network administrator for a small business is installing a computer to function as a firewall protecting their internetwork from Internet intrusion. At which of the following locations should the administrator install the firewall system? A. Anywhere on the private internetwork, as long as the Internet is accessible B. Between the Internet access router and the Internet service provider's (ISP's) network C. At the ISP's network site D. Between the Internet access router and the rest of the private internetwork

D. The firewall is a conduit between the private network and the ISP's network (which provides access to the Internet), through which all traffic must pass. This ensures that the firewall has the opportunity to examine every packet that passes between the private network and the Internet and filter out those that are not authorized. If the firewall was located in the midst of the private internetwork, it would be possible for Internet computers to bypass the firewall and communicate directly with the private systems. Placing the firewall on the far side of the router would put it on the ISP's network, causing it to filter all of the ISP's traffic and not just that destined for the private network. Installing the firewall at the ISP's site would have the same effect as installing it on the far side of the router at the private network site.

Which of the following types of documentation should indicate the complete route of every internal cable run from wall plate to patch panel? A. Physical network diagram B. Asset management C. Logical network diagram D. Wiring schematic

D. The main purpose of a wiring schematic is to indicate where cables are located in walls and ceilings. A physical network diagram identifies all of the physical devices and how they connect together. Asset management is the identification, documentation, and tracking of all network assets, including computers, routers, switches, and so on. A logical network diagram contains addresses, firewall configurations, access control lists, and other logical elements of the network configuration.

Alice is a network consultant who has been contracted to upgrade an existing Ethernet network to Gigabit Ethernet. The network consists of 20 workstations with integrated 10Base-T/100Base-TX/1000Base-T network interface adapters. The network cabling is Category 5 (CAT5) unshielded twisted pair (UTP), installed when the building was constructed. All of the workstations are connected to a single 100Base-T switch. Which of the following options would Alice find to be a valid upgrade path to Gigabit Ethernet? A. Replace the CAT5 cable with Category 5e (CAT5e) or Category 6 (CAT6) and leave the existing network interface adapters and switch in place. B. Install a 1000Base-T network interface card in each computer and leave the existing cables and switch in place. C. Replace the CAT5 cable with CAT5e or CAT6 and replace the 100Base-T switch with a 1000Base-T switch. D. Replace the 100Base-T switch with a 1000Base-T switch and leave the existing cables and network interface adapters in place.

D. The multispeed network interface adapters in the computers can run at 1 Gbps speed using the existing CAT5 cable, but the 100Base-T switch must be replaced with a 1000Base-T switch. While the network might run better with a cable upgrade, it is not immediately necessary. Replacing the network interface adapters is not necessary because the existing multispeed adapters can run at 1 Gbps if they are connected to a 1000Base-T switch

Which of the following statements best describes the difference between distributed and reflective denial-of-service (DoS) attacks?

Distributed DoS attacks use hundreds or thousands of computers that have been infected with malware, called zombies, to flood a target server with traffic, in an attempt to overwhelm it and prevent it from functioning. A reflective DoS attack is one in which the attacker sends requests containing the target server's IP address to legitimate servers on the Internet, such as DNS servers, causing them to send a flood of responses to the target. Neither attack type causes a computer to flood itself.

Which layers of the Open Systems Interconnection (OSI) model do not have protocols in the TCP/IP suite exclusively dedicated to them? (Choose all correct answers.) A. Physical B. Data link C. Network D. Transport E. Session F. Presentation G. Application

E and F. In the TCP/IP suite, the functions of the session layer are primarily implemented in the transport layer protocols: Transmission Control Protocol (TCP) and User Datagram Protocol (UDP). The presentation layer functions are often implemented in application layer protocols, although some functions, such as encryption, can also be performed by transport or network layer protocols.

Alice is the administrator of a corporate network. The company has one main site and two branch offices, and Alice is responsible for implementing WAN connections between them. The two branch offices need to upload financial information to the main office at the end of each day. This information transfer consists of database files totaling 20 to 30 GB per site. Other than the exchange of financial information, no other user traffic will be transferred between the sites, and, for security reasons, the management wants to automatically disconnect the link when it is not in use, without having to manually unplug the service cable. Cost is a factor in determining which wide area network (WAN) technology to use. Which of the following WAN technologies best suits the company's needs? A. A dedicated leased line (fractional T-1) Your selection is incorrect B. A Public Switched Telephone Network (PSTN) modem connection C. A Digital Subscriber Line (DSL) connection D. A broadband cable television (CATV) connection E. An Integrated Services Digital Network (ISDN) Primary Rate Interface (PRI) connection

E. For this scenario, the only solution that meets all the company's needs is an ISDN PRI connection. All of the specified options, except for the PSTN modem connection, provide sufficient bandwidth for the application. However, only the ISDN and PSTN links can be disconnected when not in use. Therefore, ISDN is the only possibility.

Which of the following protocols are included in a Fibre Channel packet? A. Ethernet B. IP C. TCP D. UDP E. None of the above

E. The Fibre Channel standard defines a unique, five-layer protocol stack that does not correspond to the OSI model layers. Therefore, Fibre Channel does not use Ethernet, nor does it use Transmission Control Protocol (TCP), Internet Protocol (IP), User Datagram Protocol (UDP), or any of the other TCP/IP protocols.

Ed has been hired to install network cabling for a small private company with 15 employees who need to share files and printers. All of the employees are physically located within the same building in two separate office spaces directly adjacent to each other, sharing a common wall and door for access. Both offices have drop ceilings. The client wants a simple Gigabit Ethernet installation that's easy to troubleshoot. In addition, Ed's client wants to keep installation costs to a minimum. Which of the following combinations of topology, cable type, and installation method would best meet the needs of Ed's client? A. Star topology, fiber-optic cabling, and internal installation B. Bus topology, coaxial cabling, and external installation C. Bus topology, twisted pair cabling, and internal installation D. Star topology, coaxial cabling, and external installation E. Star topology, twisted pair cabling, and external installation

E. Because the company has few employees, they are in a single location, and the client is concerned with minimizing the cost, the best solution is to use a star topology with prefabricated twisted pair cabling and an external installation method. The star topology uses a central switch. Ed can use two switches, one in each room, to connect computers to the network. Prefabricated twisted pair cabling, which has the connectors already attached and is available in specific lengths, will keep the cost to a minimum. Since the employees are all located in the same building, with a common wall and door and a drop ceiling, the external installation method is the best choice. It is not possible to use a bus topology or coaxial cable for Gigabit Ethernet. Ed could conceivably use fiber-optic cable in a star topology for Gigabit Ethernet, but it is more difficult to install and very expensive. An internal installation, which uses a combination of bulk cable with no connectors and prefabricated cables, is more expensive than an external installation and is typically used for larger networks.

Ralph has been hired to connect three local area networks (LANs) together with redundant paths that form a fault-tolerant backbone. The LANs reside on different floors in the same building and are approximately 600 meters apart. Each LAN is currently configured in a star topology using twisted pair cabling. Each LAN includes wall plates and rack-mounted patch panels and switches. Building and fire codes allow cables to run through existing risers, ceilings, and walls, but a 50,000-watt radio station occupies one of the floors between the LANs. Which topology, cable type, and installation method is best suited for this network? A. Star topology, fiber-optic cabling, and internal installation B. Star topology, coaxial cabling, and external installation C. Mesh topology, fiber-optic cabling, and external installation D. Bus topology, twisted pair cabling, and internal installation E. Mesh topology, fiber-optic cabling, and internal installation F. Star topology, twisted pair cabling, and external installation

E. Ralph should use a mesh topology with redundant fiber-optic cable runs and an internal installation method. This will meet the requirements for connecting the LANs and for providing redundancy and fault tolerance. Fiber-optic cable is immune to electromagnetic interference (EMI) and can span long distances. The internal installation method is most often used in larger networks, where end systems are geographically distant, such as different buildings and floors. The star topology will not fulfill the requirements of this backbone network since it provides no redundancy. Twisted pair cable can't span distances more than 100 meters, and it is highly susceptible to EMI. Coaxial cable can't span distances more than 500 meters, and it is also susceptible to EMI. The bus topology cannot use twisted pair cabling and doesn't support cable runs longer than 500 meters.

Identify the organizations that developed the general cable type standards for voice and data communications that are currently in use, and identify the document name. A. ANSI/TVA, document C568 B. TWA/ANSI/EIA, document T530-A C. EIA/ANSI/TWA, document 802.2 D. TDA/EIA/TIA, document 802.11 E. ANSI/TIA/EIA, document T568b

E. The three organizations that collectively developed the T568b document, which defines the standard for a structured cabling system for voice and data communications, are the American National Standards Institute (ANSI), the Telecommunications Industry Association (TIA), and the Electronic Industries Alliance (EIA). All of the other options are not standards organizations or cabling standards.

Which of the following types of cable, when installed, sometimes employed a device called a vampire tap? A. Unshielded twisted pair B. Shielded twisted pair C. Multimode fiber optic D. Single-mode fiber optic E. Coaxial

E. Thick Ethernet installations used a type of coaxial cable called RG-8. To connect a node to the network, installers ran a separate cable called an attachment unit interface (AUI) cable from the computer to the RG-8 and connected it using a device called a vampire tap that pierced the sheathing to make contact with the conductors within. All of the other cable types listed use different types of connectors.

If you need to create at least six subnets, how many bits should you use for subnetting? A 6 B 5 C 4 D 3

Explanation: Answer D is correct. The number of subnets that can be created is the number of bits used as the exponent to the number 2. So here, 2 raised to the 5th power is 32 subnets. 2 raised to the 6th power is 64. 2 raised to the 4th power is 16, and 2 raised to the 3rd power is 8.

Which two of the following are types of Integrated Services Digital Network (ISDN) circuits? A BRI B NT1 C TE1 D PRI

ISDN circuits are classified as either a Basic Rate Interface (BRI) circuit or a Primary Rate Interface (PRI) circuit. A BRI circuit contains two 64 kbps B channels and one 16 kbps D channel. A PRI circuit is an ISDN circuit built on a T1 or E1 circuit. Recall that a T1 circuit has 24 channels. Therefore, if a PRI circuit is built on a T1 circuit, the ISDN PRI circuit has 23 B channels and one 64 kbps D channel. The 24th channel in the T1 circuit is used as the ISDN D channel (that is, the channel used to carry the Q.921 and Q.931 signaling protocols, which are used to setup, maintain, and tear down connections). Answer C is incorrect. A TE1 is a device (such as an ISDN phone) that natively supports ISDN. Answer B is incorrect. An NT1 is a device that interconnects a 4-wire ISDN circuit with a 2-wire ISDN circuit.

Which of the following is a type of network, commonly used by service providers, that makes forwarding decisions based on a label contained in a 32-bit header? A Frame Relay B ATM C SONET D MPLS

Multiprotocol Label Switching (MPLS) is a technology commonly seen in service provider networks, where forwarding decisions are made based on an MPLS label (which is contained in a 32-bit MPLS header) as opposed to an IP address. This header is inserted between a packet's Layer 2 and Layer 3 headers. Therefore, MPLS is often said to be a Layer 2.5 technology. Answer A is incorrect. Frame Relay is a Layer 2 technology whose sites are interconnected using virtual circuits (VCs). Answer B is incorrect. Asynchronous Transfer Mode (ATM) is also a Layer 2 technology that uses virtual circuits. Answer C is incorrect. Synchronous Optical Network (SONET) is a Layer 1 technology that uses fiber optic cabling as its media.

Identify the quality of service (QoS) mechanism that can set a bandwidth limit on traffic and drop packets attempting to exceed that bandwidth limit. A Traffic shaping B LFI C cRTP D Policing

Policing and traffic shaping are both traffic conditioners, each of which can set a bandwidth limit on traffic. However, policing has the ability to drop excess packets, while traffic shaping delays excess traffic. Answers B and C are incorrect. Link Fragmentation and Interleaving (LFI) and RTP Header Compression (cRTP) are both link efficiency mechanisms, which attempt to make a more efficient use of relatively limited WAN bandwidth. LFI can fragment large packets and interleave smaller packets (for example, voice over IP packets) in amongst the fragmented packets. As a result, the smaller packets can exit a slow-speed interface sooner, and not experience excessive delay. cRTP can take the Layer 3 and Layer 4 headers of a Real-time Transport Protocol (RTP) packet (used to carry voice over IP traffic), which totals 40 Bytes in size, and compress them down to only two or four Bytes (two Bytes without UDP checksums and four Bytes with UDP checksums).

Which type of fiber optic connector contains two fiber strands in a single connector? A MTRJ B ST C SC D LC

The most unique characteristics of a media termination recommended jack (MTRJ) connector is that two fiber strands (that is, a transmit strand and a receive strand) are included in a single connector. An MTRJ connector is connected by pushing the connector into the terminating device, and it can be removed by pulling the connector from the terminating device.

Collision Domain

The part of the network where packet collisions can occur. A collision occurs when two devices send a packet at the same time on the shared network segment. The packets collide and both devices must send the packets again, which reduces network efficiency. Collisions are often in a hub environment, because each port on a hub is in the same collision domain. By contrast, each port on a bridge, a switch or a router is in a separate collision domain. Remember, each port on a hub is in the same collision domain. Each port on a bridge, a switch or router is in a separate collision domain.

Which of the following is a type of network interface device (NID) that includes circuitry to perform such functions as converting between framing formats on a digital circuit? A Smart jack B Demarc C NT1 D Tip and ring

nswer A is correct. A smart jack is a type of network interface device (see the definition for demarc) that adds circuitry. This circuitry adds such features as converting between framing formats on a digital circuit (for example, a T1), supporting remote diagnostics, and regenerating a digital signal. Answer B is incorrect. A demarcation point (also known as a demarc or a demarc extension) is the point in a telephone network where the maintenance responsibility passes from a telephone company to the subscriber (unless the subscriber has purchased inside wiring maintenance). This demarc is typically located in a box mounted to the outside of a customer's building (for example, a residential home). This box is called a network interface device (NID). Answer D is incorrect. The tip and ring wires are the red and green wires found in an RJ-11 wall jack, which carry voice, ringing voltage, and signaling information between an analog device (for example, a phone or a modem) and a telephone's wall jack. Answer C is incorrect. An NT1 is an ISDN device that interconnects a 4-wire ISDN circuit with a 2-wire ISDN circuit.

Your company has been assigned the 172.16.0.0/16 network for use at one of its sites. You need to use a subnet mask that will accommodate 42 subnets while simultaneously accommodating the maximum number of hosts per subnet. What subnet mask will you use? A /20 B /22 C /24 D /16

nswer B is correct. The number of subnets created by a specific number of borrowed bits can be calculated with the formula: Number of Subnets = 2^s, where s is the number of borrowed bits. If you raise 2 to the power of 5, you get 32. If you raise 2 to the power of 6, you get 64. You need to create a subnet mask that will accommodate 42 subnets for this question, while maximizing the number of host addresses available per subnet. Since five borrowed bits are not sufficient, you need to use six borrowed bits (which is more than enough). You do not want to use more than six borrowed bits, because you would not be maximizing the number of available host IP addresses per subnet. Since you are working with a network address of 172.16.0.0/16, adding the six borrowed bits to the /16, you get a subnet mask of /22. Answer D is incorrect. A /16 subnet mask only supports a single subnet for the 172.16.0.0/16 network. Answer A is incorrect. A /20 subnet mask only supports sixteen subnets for the 172.16.0.0/16 network. Answer C is incorrect. A /24 subnet mask supports 256 subnets for the 172.16.0.0/16 network, which does not maximize the number of available host addresses per subnet.