NCTI 3 to 4
Which statement best describes network address translation (NAT) masquerading?
It hides all internal addresses behind one external address.
What best describes orthogonal frequency division multiplexing (OFDM)?
It is a multicarrier transport scheme in which narrowband carriers (subcarriers) are modulated independently, and then multiplexed together.
What is the best description of the Internet protocol (IP) address prefix?
It is the shorthand notation for the combined network and subnet mask.
In what type of installation is wide wavelength division multiplexing (WWDM) used?
It is used in passive optical networks (PON).
When using multipath routing and multiple routes are available for a single destination address, how does the router make the route selection?
It selects the route with the highest precedence.
The Open Systems Interconnection reference model (OSI/RM) Network Layer serves which primary purpose?
It uses Layer 3 addresses to create multiple routed networks.
What authentication and directory services does an Apple Mac OS X/macOS server employ?
Kerberos, Active Directory (AD) connector, and RADIUS.
Which of the following is developed as a CD-based Debian-like distribution, or design, to run off the CD drive?
Knoppix.
In the five-layer hierarchy of Apple's operating systems, Mac OS X/macOS, which layer is most complex?
Layer five, the application layer containing Cocoa and Carbon.
Port addresses and network addresses are two types of:
Logical addresses.
With what synchronous optical network (SONET) standard is 10GBase-EW/LW/SW compatible?
OC-192.
Which hypertext transfer protocol (HTTP) message request from the client allows it to obtain additional information regarding options and requirements without initiating any actions on the part of the server?
OPTIONS.
Which one of the following protocols allows email clients to download their messages from an email server?
Post Office Protocol version 3 (POP3).
Internet protocol (IP) and X.25 are considered to be which of the following?
Protocols for the Network Layer.
Why are routers known as neighbors or peers?
Because they exchange routing information.
What are the common file extensions used to transfer image data in file transfer protocol (FTP)?
Bitmap (.BMP), graphics interchange format (GIF), and joint photography experts group (.JPG or .JPEG).
Layer 3 switches do a good job of containing which of the following?
Broadcasts.
How does frequency division multiplexing (FDM) enable multiple signals to share a common medium?
By assigning each signal a specific frequency or band of frequencies called a channel.
What are the units called that transport asynchronous transfer mode (ATM) data?
Cells.
The address 68.56.189.17 belongs to which Internet protocol (IP) class?
Class A
What type of process is located on two computers that perform approximately the same services?
Client.
Which of the following Dynamic Host Configuration Protocol (DHCP) codes carries vendor-specific options in a private network?
Codes 128-256.
Devices connected to hubs share the same:
Collision domain.
What is the Linux shell?
Command interpreter and scripting language.
What does the Domain Name System (DNS) allow users to do?
Distinguish between two similar names.
What service on an Apple Mac OS X/macOS server enables multiple computers to work together on a single task?
Distributed computing with Xgrid.
Host names and uniform resource locators (URL) are resolved to Internet protocol (IP) addresses by which of the following applications?
Domain Name System (DNS).
What network and virtual private network (VPN) services does an Apple Mac OS X/macOS server employ?
Domain name system (DNS), dynamic host configuration protocol (DHCP), network address translation (NAT), firewalling, and network time protocol (NTP).
Coarse wavelength division multiplexing (CWDM) applications were expanded to include use in large metropolitan networks, utilizing wavelengths in what band??
E-band.
All computers running on the transmission control protocol/Internet protocol (TCP/IP) suite have which of the following in common?
Each computer is assigned its own Internet protocol (IP) address.
When an application is sending data to a distant computer, what process occurs on the sending node?
Encapsulation.
What entry would be made to log each hop along the way to a specific Internet site?
Enter "tracert" followed by a host name for the Internet site.
Under what license is Linux released?
GNU General Public License (GPL).
When network address translation (NAT) uses IP (Internet protocol) address translation, it assigns external addresses to internal devices in which way?
It assigns the internal address to one of a pool of external addresses.
Which Linux distribution has the distinction of being the oldest surviving Linux distribution that is known for its stability?
Slackware.
Which file handles Samba Server Configuration in Linux?
Smb.conf.
What Open Source mail filter does an Apple Mac OS X/macOS server use for junk mail filtering?
SpamAssassin.
What can cause routing loops in the flat router architecture?
The router receives data packets before it receives routing information, causing the router to generate additional address-request messages for routing information.
A router makes its packet forwarding decision based on what information?
The router's routing table.
In Simple Network Management Protocol (SNMP), when do passive management agents take action on their own initiative?
When certain well-defined error conditions occur they generate an unsolicited message called a trap.
When a client connects to a web browser, the first action is typically media access control (MAC) address resolution. Under what circumstance may address resolution be bypassed?
When the client has recently made a request to the same server.
What are some common applications included with Mac OS X/macOS in an Apple computer?
iMovie, iTunes and GarageBand.
What is the primary reason to build a virtual local area network (VLAN)?
To minimize broadcast traffic.
Why does Simple Network Management Protocol (SNMP) use unsolicited messages (traps) from the network elements to poll for appropriate information?
Using traps is consistent with the goal of simplicity and minimizing the amount of traffic generated by the network management function.
Which version of the packet-based multimedia communications system, covered by the H.323 standard, was the first to standardize requirements for communications between a PC-based telephone and a telephone on the switched circuit network (SCN) of the public telephone system?
Version 2.
Which Linux tool allows you to run Windows applications natively on an x86 platform?
WINE.
Which represents the prefix bits for the subnet mask 255.255.0.0?
/16.
Where does Red Hat store networking parameters?
/etc/sysconfig directory
Which network address represents a default route?
0.0.0.0/0.
What server management services are installed on an Apple Mac OS XmacOS server?
Simple network management protocol version 3 (SNMPv3), Secure Shell access, and server monitor.
On which network type is a static route best used?
Stub routing.
What is the primary difference between transmission control protocol (TCP) and user datagram protocol (UDP)?
TCP messages are tracked to ensure they are received; UDP messages are sent without tracking.
The most commonly used dense wavelength division multiplexing (DWDM) channels in broadband cable networks are in which band?
The C-band (1,530 to 1,565 nm).
What happens when the browser application finishes downloading the files necessary to display a web page?
The browser and server drop the connections, and the browser maintains the page and its elements in local memory.
What is the Dynamic Host Configuration Protocol (DHCP) client/server components?
The client requests parameters and the server provides the parameters.
What happens to a datagram sent by a higher level protocol to a 127.x.y.z address?
The datagram loops back inside the host and never leaves the network interface card (NIC).
Which router protocol type shares routing information within the autonomous system (AS)?
Interior Gateway Protocol (IGP).
What are routers that belong to the same autonomous system (AS) called?
Interior neighbors.
Which of the following commonly is used to classify networks?
The distance between the computer and the server
What component of the packet-based multimedia communications system, covered by the H.323 standard, is considered to be the "brain" of the network?
The gatekeeper.
What network information can be determined from a logical Internet protocol (IP) address?
The host portion and network portion.
A store-and-forward email system will not deliver messages until:
The host requests the information.
Which email protocol enables the messages to be viewed without first downloading them from the email server?
Internet Message Access Protocol version 4 (IMAP4).
Which of the troubleshooting utilities presented is frequently used as a starting point for transmission control protocol/Internet protocol (TCP/IP) network problem isolation to learn what network a device resides on?
Ipconfig.
Why is subnetting used?
It allows network administrators to break up a single network address into smaller network addresses.
Which ping option allows you to specify the packet buffer size for each ping packet?
Ping -l.
Which of the following is used to verify whether another host on a transmission control protocol/Internet protocol (TCP/IP) network is reachable?
Ping.
Which of the troubleshooting utilities presented expects a reply when it sends a message to another computer?
Ping.
Which protocol allows a diskless workstation to contact a server and obtain an Internet protocol (IP) address?
Reverse address resolution protocol (RARP).
Where does the Domain Name System (DNS) namespace begin?
Root domains.
Which device evaluates and acts upon a packet's Internet protocol (IP) address?
Router.
Which transmission control protocol (TCP) header control bit represents that the message is initiating a connection?
SYN.
Which application allows Linux to share files and printers with Microsoft Windows devices?
Samba.
What services are typically included in Apple's Mac OS X/macOS server?
Services a company would need to operate a business.
What is the maximum length of a 10GBase-T Ethernet connection using category 7 (CAT-7) shielded twisted-pair (STP) cable?
100 m.
What is the binary equivalent of decimal 136?
10001000.
Convert the Internet protocol (IP) address 172.68.10.2 from decimal to binary:
10101100.01000100.00001010.00000010.
Convert the binary Internet protocol (IP) address 01110011.11001000.00101100.00000010 to decimal:
115.200.44.2.
Which user datagram protocol (UDP) port address do simple network management protocol (SNMP) agents use to send and receive management requests?
161.
Which is the result of ANDing the Internet protocol (IP) address 23.176.224.18 with the subnet mask 255.224.0.0?
23.160.0.0.
The maximum Domain Name System (DNS) domain name length is how many bytes?
255.
Which is the Internet protocol (IP) header protocol number used to specify that the packet's contents were created with transmission control protocol (TCP)?
6.
What is the correct destination of a user datagram protocol (UDP) port number for a DHCPDISCOVER message?
67.
If we borrow 3 bits from a Class C network address, how many useable subnets have we created?
8.
What is Ethernet?
A Data Link Layer specification for media access control (MAC), which defines how network nodes can use a shared medium to transmit signals to one another.
The Mac OS X/macOS kernel includes which elements?
A Mach kernel, XNU kernel, and various Berkeley Software Distribution (BSD) system calls.
What provides user datagram protocol (UDP) with the ability to demultiplex data for an application?
A UDP destination port number.
On the file transfer protocol (FTP) server, what manages client requests for file retrieval or transmission?
A daemon.
What type of server maintains an access log to assist with troubleshooting and tracking down malicious users?
A file transfer protocol (FTP) server.
Virtual local area networks (VLAN) are typically implemented using which type of device?
A gateway.
What isolates an Internet protocol (IP) address's network portion from its host portion?
A network mask.
Which of the following best describes the difference between a process and a program?
A process is a subset of a program.
The interaction between processes and protocols forms which of the following?
A protocol stack.
What determines the length of a time division multiplexing (TDM) frame?
The number of input channels to the multiplexer.
You know the logical address of an associate's computer on the company's local network and you want to learn the media access control (MAC) address of your associate's computer. Which of the following tools would you use?
Address resolution protocol (ARP).
Which of the following accurately describes a bus topology?
All devices are connected by a single electrical circuit.
At which point in the Dynamic Host Configuration Protocol (DHCP) lease period does the client first attempt to renew its lease?
At 50% of the original lease time.
How would an operator find a list of options available for the ping utility?
Type "ping" from a command line.
Which of the following two ports are contained in the transmission control protocol (TCP) header?
Destination and source.
Which layer in the OSI reference model is the only layer that adds a trailer to the data it transmits?
Data Link Layer.
What are some issues that can arise when making a file available for transfer to other users?
Data type, file structure, and transmission mode.
The Network Layer must do what to a received frame first, in order to determine the route over which it will forward the datagram to the next network?
Decapsulate the packet.
Ipconfig displays which of the following elements of client configuration information?
Default gateway.
Which Internet protocol (IP) packet fragmentation header field specifies where the fragment belongs in the original datagram?
Fragment Offset.
Which Layer 2 switch type reads the first 64 bytes of a frame and then forwards it to the destination interface?
Fragment-free.
Which is the most important of the network troubleshooting steps?
Identify the exact issue.
Which Linux tool is used for monitoring and changing network parameters?
Ifconfig.
Which Linux application supports centralized user authorization and directory services?
OpenLDAP.
What applications are available in Apple iWork?
Pages, a word processing application; Numbers, a spreadsheet application; and Keynote, a presentation application.
What does the packet-based multimedia communications systems, covered by the H.323, cover?
Realtime audio, video, and data communications over Internet protocol (IP) packet networks.
Zones maintain domain name information in which record types?
Resource records.
What is the name of the protocol by which management information for a network element can be inspected or altered by a management station?
Simple Network Management Protocol (SNMP).
Hypertext transfer protocol (HTTP) is what type of protocol?
Stateless.
Which of the following is a characteristic of static routing?
Static systems do not operate well in an environment of rapid growth or change.
How are store-and-forward Ethernet switches different from cut-through switches?
Store-and-forward switches are more accurate, but cut-through switches are faster.
What type of delivery method uses an email server between the sender and the receiver of messages?
Store-and-forward.
The physical address of a device is processed by which layer of the Open Systems Interconnection reference model (OSI/RM)?
The Data Link Layer.
A repeater operates at which layer of the Open Systems Interconnection reference model (OSI/RM)?
The Physical Layer.
Transmitting messages from a sending computer process to a receiving computer process is the function of which layer of the Open Systems Interconnection (OSI) model?
The Transport Layer.
Which layer of the Open Systems Interconnection reference model (OSI/RM) would you suspect as being the problem when packets are arriving at the server but no information is being returned to the client?
The Transport Layer.
What is an X.25 network, whether public or private, typically built upon?
The leased-line facilities of the public telephone network.
In a net mask address, what identifies the network and host portions of the address?
The network portion of the net mask is set to all ones, and the host is set to all zeros.
In a synchronous optical network (SONET) what is the basic building block having a data transmission rate of 51.84 Mbps?
The synchronous transport signal (STS) frame.
The five steps of (1) obtaining logical addresses, (2) obtaining physical addresses, (3) establishing a connection between applications, (4) the transfer of information, and (5) the termination of the connection are necessary to accomplish what?
The transfer of information across a transmission control protocol/Internet protocol (TCP/IP) network.
How does IEEE 802.3 frame format differ from Ethernet Version 2 frame format?
The type field is replaced with the length field.
Distance Vector Algorithms (DVA) operate in which manner?
They advertise their routing tables to directly connected neighbor routers.
What is an inefficient characteristic of synchronous time division multiplexing (TDM) that is addressed by statistical TDM?
Transport of empty time slots.
What are the primary requirements to connect to a transmission control protocol/Internet protocol (TCP/IP) network?
Unique pairs of Network Layer and Transport Layer addresses and use of the TCP/IP protocol suite.
Which utility should be run to verify that your Windows client is configured to use the correct Domain Name System (DNS) server?
ipconfig.
When troubleshooting, asking the question, "Has anything changed recently that might have had an impact?",
will aid you in: Identifying the exact issue relating to a problem.
