Q.1

Synchronous protocols

  • transmit characters one at a time
  • allow faster transmission than asynchronous protocols do
  • are generally used by personal computers
  • are more reliable
  • None of the above
Q.2

What is the maximum number of entries in the HOSTS file?

  • 8
  • 255
  • 500
  • Unlimited
  • None of the above
Q.3

The communication mode that supports data in both directions at the same time is

  • simplex
  • half-duplex
  • full-duplex
  • multiplex
  • None of the above
Q.4

An error-detecting code inserted as a field in a block of data to be transmitted is known as

  • Frame check sequence
  • Error detecting code
  • Checksum
  • flow control
  • None of the above
Q.5

The cheapest modems can transmit

  • 300 bits per second
  • 1,200 bits per second
  • 2,400 bits per second
  • 4,800 bits per second
  • None of the above
Q.6

Which of the following is an advantage to using fiber optics data transmission?

  • resistance to data theft
  • fast data transmission rate
  • low noise level
  • few transmission errors
  • All of the above
Q.7

Which of the following statement is incorrect?

  • if a host moves from one network to another, its IP address must change
  • routing uses the network portion of the IP address, the path taken by packets travelling to a host with multiple IP addresses depends on the address used.
  • IP addresses encode both a network and a host on that network, they do not specify an individual machine, but a connection to a network.
  • All of the above
  • None of the above
Q.8

Which of the following communications service provides message preparation and transmission facilities?

  • Teletex
  • Teletext
  • x400
  • Fax
  • None of the above
Q.9

Four bits are used for packet sequence numbering in a sliding window protocol used in a computer network. What is the maximum window size?

  • 4
  • 8
  • 15
  • 16
  • None of the above
Q.10

What is the default subnet mask for a class A network?

  • 127.0.0.1
  • 255.0.0.0
  • 255.255.255.0.0
  • 255.255.255.0
  • None of the above
Q.11

Which of the following device is used to connect two systems, especially if the systems use different protocols?

  • hub
  • bridge
  • gateway
  • repeater
  • None of the above
Q.12

You have a class A network address 10.0.0.0 withsubnets, but are required to addnew subnets very soon. You would like to still allow for the largest possible number of host IDs per subnet. Which subnet mask should you assign?

  • 255.240.0.0
  • 255.248.0.0
  • 255.252.0.0
  • 255.254.0.0
  • 255.255.255.255
Q.13

To make possible the efficient on-line servicing of many teleprocessing system users on large computer systems, designers are developing

  • communication systems
  • multiprogramming systems
  • virtual storage systems
  • All of the above
  • None of the above
Q.14

Which of the following best describes the scopes on each DHCP server, in the absence of configuration problems with DHCP addresses, if you use multiple DHCP servers in your environment?

  • Unique to that subnet only
  • For different subnets
  • For no more than two subnets
  • For no subnets
  • None of the above
Q.15

What is the port number for NNTP?

  • 119
  • 80
  • 79
  • 70
Q.16

Contention is

  • One or more conductors that serve as a common connection for a related group of devices
  • a continuous frequency capable of being modulated or impressed with a second signal
  • the condition when two or more stations attempt to use the same channel at the same time
  • a collection of interconnected functional units that provides a data communications service among stations attached to the network
  • None of the above
Q.17

A T-switch is used to

  • control how messages are passed between computers
  • echo every character that is received
  • transmit characters one at a time
  • rearrange the connections between computing equipment
  • None of the above
Q.18

An anticipated result from multiprogramming operations is:

  • reduced computer idle time
  • the handling of more jobs
  • better scheduling of work
  • All of the above
  • None of the above
Q.19

Who originally designed TCP/IP?

  • The Department of Defense
  • Novell
  • IBM
  • Xerox
Q.20

What is the usual number of bits transmitted simultaneously in parallel data transmission used by microcomputers?

  • 16
  • 9
  • 8
  • 4
  • None of the above
Q.21

Data are sent over pin _____ of the EIA-interface.

  • 2
  • 3
  • 4
  • All of the above
Q.22

To set up a bulletin board system you need

  • a smart modem with auto-answer capabilities
  • a telephone line
  • a personal computer
  • All of the above
  • None of the above
Q.23

When using the loopback address, if TCP/IP is installed correctly, when should you receive a response?

  • Immediately
  • Only if the address fails
  • After the next host comes online
  • Within two minutes
  • None of the above
Q.24

The synchronous modems are more costly than the asynchronous modems because

  • they produce large volume of data
  • they contain clock recovery circuits
  • they transmit the data with stop and start bits.
  • they operate with a larger bandwidth
  • None of the above
Q.25

What are the most commonly used transmission speeds in BPS used in data communication?

  • 300
  • 1200
  • 2400
  • 9600
  • None of the above
Q.26

Eight stations are competing for the use of a shared channel using the 'Adaptive tree Walk Protocol'. If the stations 7 and 8 are suddenly become ready at once, how many bit slots are needed to resolve the contention?

  • 7 slots
  • 5 slots
  • 10 slots
  • 14 slots
Q.27

The Internet Control Message Protocol (ICMP)

  • allows gateways to send error a control messages to other gateways or hosts
  • provides communication between the Internet Protocol Software on one machine and the Internet Protocol Software on another
  • reports error conditions to the original source, the source must relate errors to individual application programs and take action to correct the problem
  • All of the above
  • None of the above
Q.28

Avalanche photodiode receivers can detect hits of transmitted data by receiving

  • 100 photons
  • 200 photons
  • 300 photons
  • 400 photons
  • None of the above
Q.29

The geostationary satellite used for communication systems

  • rotates with the earth
  • remains stationary relative to the earth
  • is positioned over equator
  • All of the above
  • None of the above
Q.30

How many bits internet address is assigned to each host on a TCP/IP internet which is used in all communications with the host?

  • 16 - bits
  • 32 - bits
  • 48 - bits
  • 64 - bits
  • None of the above
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