Chapter 7

A technician is configuring a new SOHO multifunction router at a customer site to provide network access to several wireless devices. The technician is required to protect the internal network from unauthorized access while performing the initial router setup as well as during normal operation after the configuration is completed.Which of the following is the best step for the technician to take in securing the router to meet this requirement?

Change the router's default administrative password.

You run the ipconfig /all command on your Windows computer and see a hexadecimal value that looks like this: E0-70-EA-4E-AB-A5What does it represent? Select two.

Physical address Correct. The Physical address is the same as the MAC address burned-in to the NIC. It cannot be changed by conventional means and is globally unique. MAC address Correct. The MAC address is the same as the physical address burned-in to the NIC. It cannot be changed by conventional means and is globally unique.

Jesenia read an article that said stored data, such as when you are downloading an app, is transmitted using TCP, but live-streaming events are transmitted using UDP. Why would this be true? Select two.

UDP is fast and does not retransmit lost data so as not to disrupt the live video feed. Correct. Live stream video feeds and real-time calls using Voice over IP are best delivered in a continuous stream so as not to disrupt the experience. If a live-stream video packet is lost, the video quality may be degraded for a second. If a voice packet is lost, the recipient could ask to repeat the statement. TCP is reliable and ensures the delivery of data using a connection-oriented mechanism. Correct. TCP (Transmission Control Protocol) is reliable and uses a connection-oriented mechanism to guarantee the delivery of data. It expects an acknowledgement from the destination. If it does not receive one, it resends the data.

Henry is using the command line to troubleshoot whether a Windows client is able to connect to the server on his network.What command should Henry use to check whether he has connectivity to the server?

ping

Quintavius loves to tinker with computers so he sets off to see how many networking services he can install in one physical server. He sets up the system to support DCHP, DNS, HTTP, HTTPS, Telnet, SSH, and an email server. On what port will these services listen?

(DCHP 443, DNS 23, HTTP 80, HTTPS 22, Telnet 25, SSH 67, SMTP 53 Incorrect. DHCP listens on port 67; it is used to assign IP addresses to computers automatically. DNS listens on port 53; it resolves domain names into IP addresses. HTTP listens on port 80; it serves online resources, but it is not secure. HTTPS listens on port 443; it serves web pages securely. Telnet listens on port 23; it is used for remote access, but transmissions are not encrypted so it is not secure. SSH listens on port 22 and is used for remote access. SSH is secure because the transmissions are encrypted. SMTP listens on port 25 and is used to send and receive email messages between email servers.

A technician wants to configure a DHCP server to guarantee that certain printers always receive the same address. Which of the following should the technician configure?

(not vpn tunnel

Makani is participating in an on-the-job training program at work. He is learning how to configure computers in a network. He is told to use private IP addresses because all organizations could use them without conflict since they are not routable.If the addresses are not routable, he wonders, how will the computers have internet access?

A NAT router will translate a private address to a public one

Ramah is preparing a presentation on networking terminology. She wants to ensure everyone understands the difference between a node and a host. How should she define these terms? Select three.

A node is not used to run a variety of applications. Correct. Depending on the network, a node that is not a host typically provides a specialized function such as a router, switch, or a printer. It is not a general-purpose computing device that provides client/server functionality. A smart thermostat is an example of a node. Correct. Devices that connect to the network such as routers, switches, hubs and even smart thermostats are considered nodes. A node that is not a host does not typically provide client/server functionality as would a web, DHCP, or DNS server. Every host is a node, but not every node is a host. Correct. All hosts and nodes have an IP address and are accessible through the network. However, a host is a general-purpose computer and can be either a client or a server. Depending on the network, a node that is not a host typically provides a specialized function such as a router, switch, or a printer.

A technician wants to configure a DHCP server to guarantee that certain printers always receive the same address. Which of the following should the technician configure?

Address reservation Correct. An address reservation can be configured on a DHCP server to always assign the same IP address to a network host. When the host queries the DHCP server, the server checks the MAC address of the host and assigns the appropriate preconfigured IP address.

You log in to a wireless router with administrative privileges and change the SSID. What exactly have you done?

Changed the network name Correct. The network name for a wireless router is the SSID (Service Set Identifier). When you connect to a wireless network, you may see multiple networks names available for selection; these are the SSIDs. Most are secure so you will need a password to connect.

A small company has a few users that are spending too much time on specific social media web sites; this is affecting their productivity at work. The manager asks if it is possible to limit access to those sites.Which of the following will satisfy the request while not limiting access to other websites?

Configure a proxy server as an internet appliance to limit access to the web sites. Correct. A proxy server is a computer that can be configured to intercept web traffic to, among other things, limit access to certain web sites.

A client contacted you to request your help in researching and supplying the hardware necessary to implement a SOHO solution at his new home-based business.Which of the following SOHO router features will simplify IP address configuration on the private network for both wired and wireless clients?

DHCP server Correct. An integral feature of a SOHO router is the DHCP (Dynamic Host Configuration Protocol) server, which automatically assigns IP address information to network clients with either wired or wireless connections. The host device is configured to obtain IP address information automatically.

You are a security professional tasked with preventing fraudulent emails. Which DNS records will you configure to help you realize this goal? Select three.

DKIM Correct. The DKIM (DomainKeys Identified Mail) record authenticate that an email message came from a trusted source. SPF Correct. (Sender Policy Framework) record helps protect against email spoofing by informing the receiving email server which servers can send emails from your domain.DMARC Correct. The DMARC (Domain-based Message Authentication, Reporting, and Conformance) records tell the receiving email server what to do when it receives fraudulent emails. DMARC

You are setting up your Windows computer to connect to the Internet. When you type www.microsoft.com, the issues an error message indicating the site cannot be reached.What network setting should you check to see the address of the server being used to resolve the domain name you entered in the browser?

DNS Correct. The DNS address is used to connect to a DNS (domain name system) server that is used to resolve the domain name. This allows you to use a name like www.microsoft.com instead of trying to remember the IP address of the Microsoft web server.

Which of the following devices are most commonly used to connect a LAN to an ISP for broadband services? (Select TWO.)

DSL modem Correct. A DSL modem is the hardware device used to connect the local area network (LAN) to an Internet service provider (ISP). DSL is a broadband technology transported over copper POTS (plain old telephone service) cable that can provide high-speed Internet alone (SDSL) or Internet combined with voice (ADSL, VDSL). Cable modem Correct. The cable modem is the hardware device used to connect the local area network (LAN) to a cable Internet service provider (ISP). Cable is a broadband technology transported over a coaxial cable that can provide high-speed Internet, TV, and voice via a single cable connection.

Gulliver is trying to determine why one of the computers at work cannot connect to the network. He thinks it might be DHCP related but wants to rule out the computer itself as being the problem. Gulliver manually configures the network settings that will allow the computer to connect to the network. What three values does he configure? Select three.

Default Gateway Correct. The default gateway is the address of the router connected to the local network. When sending a message to another network, a device will send the message to the router (default gateway), and the router will forward the message based on entries in its routing table. In larger networks, the default gateway could be a layer 3 switch instead of a router. A layer 3 switch has switching and routing capabilities . IP address Correct Answer Subnet Mask

You buy a cable that has RJ-45 connectors. For what type of transmission will the cable be used?

Ethernet Correct. Ethernet patch cables are copper twisted pair cables using RJ-45 connectors. RJ-45 connectors are constructed to accept up to four pairs of individual wires.

Which of the following is a scenario in which an IT support technician would most likely be required to implement the alternate IP configuration method on a network host?

In the event a DHCP server is unavailable, the workstation will have a valid IP address on the subnet. Correct. The most common use of the alternate IP configuration method is to assign a valid IP address to a host when it cannot reach a DHCP server. For example, a client uses her laptop at home (using DHCP) and at work (using static assignment). If the host is set to obtain an IP address automatically, it will receive an IP address at home but not at work. Without an alternate configuration, if the host cannot reach a DHCP server, the host will automatically assign an automatic private Internet protocol address (APIPA).

The owner of a small loan brokerage firm does not know much about computers but has always been concerned with security, so he buys a used enterprise grade router. Mango, a loan officer with a little bit of IT knowledge, configures FE80::1 as the only address on the internal interface of the router. What effect will this have?

Internet access will now be suppressed. Correct. FE80::1 is a link-local IPv6 address; it is not routable. Configuring a global unicast address will allow devices to have internet access.

Cathy wants to connect to her wireless LAN at home but is not sure where to change the setting so that she can connect.Where in the Windows Control Panel will Cathy find her computer's network connection settings?

Network and Sharing Center Correct. Cathy will find the computer's network connection settings in the Network and Sharing Center. She will also see all the network connection types.

You are running a performance test using three different browsers on the same computer to simultaneously access the same web site. What numeric identifier or address is used to keep the three connections separate at the application (browser) level?

Port number Correct. The port number is used to identify the application or service running on the host. It is used to create a socket which is the combination of the IP address and the port number such as 192.168.1.1:8000. The IP address identifies the host, and the port number identifies the application or service running on the host. Since the three browsers are running on the same system, the socket will have the same IP address, but each will have a different port number to help keep the three connections or conversations separate. The source port number is assigned randomly, but the destination port number for the service being requested, HTTP (web server), is 80 (443 for HTTPS).

Kwan, a fifth-grade teacher, has been learning about computers but does not know much about networking. He found a hub in the supply closet and decided to create a small network in his classroom consisting of a file/application server, 10 relatively new computers, and a printer. The students often complain that the computers are slow, but one student blames it on the network. What can Kwan do to eliminate complaints?

Replace the hub with a switch Correct. Hubs employs older technology, operate at 10/100 Mbps, and share the bandwidth with all the devices connected to it. This means signals will collide and delay transmissions as the network recovers. A modern-day switch has 1 Gbps ports and every port is capable of operating at that speed because the bandwidth is not shared. There are network design considerations that need to be taken into account but a switch will outperform a hub in all cases.

Venus is a member of the IT department at a company that has a moderately-sized network. One of her performance review objectives is to help her department be more proactive relative to being notified, and responding to, certain events that occur in the network. What type of server will help her meet the objective?

Syslog Server Correct. A syslog server gathers information about various network devices and stores the events into a database. Syslog messages have a numeric identifier to denote the severity of the event.

A restricted computer lab at a college has been set up with local authentication. Students are able to log in but do not have internet access. You check the network settings on one of the computers and it has an IP address of 169.254.1.10. What is the problem?

The DHCP server is not reachable Correct. When a computer is configured to request an IP address from a DHCP server on power up, and the DHCP server is not available or reachable, the operating system will assign an address in the 169.254.x.y address space (APIPA, Automatic Private IP Addressing). This allows devices in the local network to have connectivity with each other but not with computers on another network, hence internet access is not possible. The host will transmit a DHCP discover message periodically in an attempt to obtain an address from a DHCP server.

Akello uses his computer to download a document from the internet. What role does his computer play as opposed to the computer from which he is downloading the document? Select two.

The computer from which he downloads the document is a server Correct. In a client/server model, the device initiating the request is the client and the machine that responds to the request, and services that request, is the server. The client application is the browser Akello is using, and the system supplying the resource is the web server. His computer is a client Correct. In a client/server model, the device initiating the request is the client and the machine that responds to the request, and services that request, is the server. The client application is the browser Akello is using, and the system supplying the resource is the web server.

Torino receives a call from a SOHO client who says her computer is not working. He goes to her office and checks the network settings. He notices that the default gateway entry is blank, yet he can ping the router. Once he enters the default gateway, the problem is solved. What did the client mean when she said her computer is not working?

The computer had no internet access Correct. If the default gateway is not set, the computer will not be able to send traffic outside of the local network. He can ping the default gateway because the router interface is part of the local network. The address on the router interface is the default gateway but the computer does not know this unless it is explicitly configured either manually or automatically using DHCP.

What characteristics do the 10.0.0.1/24, 172.16.0.2/24, and 192.168.0.3/24 IP addresses have in common? Select three.

They are private IP addresses. Correct. The range of private IP addresses is 10.0.0.0 - 10.255.255.255, 172,16.0.0 - 172.31.255.255, and 192.168.0.0 - 192.168.255.255. They can be used internally by any organization and will not create a conflict because they are not routable. They are not routable by the ISP. Correct. Private IP addresses are not routable and can be used internally by any organization. If an ISP router encounters a packet with any one of these addresses, it will drop the packet (not forward it). They all have the same subnet mask. Correct. The /24 is using the CIDR notation. This means that the first 24 bits of the address represent the network portion. It is an alternate way of representing the subnet mask which is used to help computers determine if the destination device is on the local network or on another network.

You are asked to add a resource record in the DNS namespace for a website your company wants to publish. Which of the following entries will you make?

www.company.com A IN 14440 209.165.200.5 Correct. The proper format is resource name (www.company.com), record type (A), class code (IN), TTL (14400), Data (209.168.200.5). The record type of A is the address record and points a host name to its IP address. The class code IN means the record is allowed on the internet.  The TTL is the time-to-live and represents the time a server can hold the record in its cache. The data is the IP address mapped to the host.