Practice | Hashtable

51. Which of the following is used for modulation and demodulation?

A. modem

B. protocols

C. gateway

D. multiplexer

Discuss

52. Which of the following is not a disadvantage of wireless LAN?

A. Slower data transmission

B. higher error rate

C. interference of transmissions from different computers

D. All of the above

Discuss

53. The Internet Control Message Protocol (ICMP)

A. allows gateways to send error a control messages to other gateways or hosts

B. provides communication between the Internet Protocol Software on one machine and the Internet Protocol Software on another

C. reports error conditions to the original source, the source must relate errors to individual application programs and take action to correct the problem

D. All of the above

Discuss

54. Your company has a LAN in its downtown office and has now set up a LAN in the manufacturing plant in the suburbs. To enable everyone to share data and resources between the two LANs, what type of device(s) are needed to connect them? Choose the most corre

A. Modem

B. Cable

C. Hub

D. Router

Discuss

55. The term 'duplex' refers to the ability of the data receiving stations to echo back a confirming message to the sender. In full duplex data transmission, both the sender and the receiver

A. cannot talk at once

B. can receive and send data simultaneously

C. can send or receive data one at a time

D. can do one way data transmission only

Discuss

56. How many hosts are attached to each of the local area networks at your site?

A. 128

B. 254

C. 256

D. 64

Discuss

57. Which of the following technique is used for fragment?

A. a technique used in best-effort delivery systems to avoid endlessly looping packets

B. a technique used by protocols in which a lower level protocol accepts a message from a higher level protocol and places it in the data portion of the low level frame

C. one of the pieces that results when an IP gateway divides an IP datagram into smaller pieces for transmission across a network that cannot handle the original datagram size

D. All of the above

Discuss

58. Contention is

A. One or more conductors that serve as a common connection for a related group of devices

B. a continuous frequency capable of being modulated or impressed with a second signal

C. the condition when two or more stations attempt to use the same channel at the same time

D. a collection of interconnected functional units that provides a data communications service among stations attached to the network

Discuss

59. Avalanche photodiode receivers can detect hits of transmitted data by receiving

A. 100 photons

B. 200 photons

C. 300 photons

D. 400 photons

Discuss

60. Satellite-Switched Time-Division Multiple Access (SS/TDMA) is

A. the method of determining which device has access to the transmission medium at any time.

B. a medium access control technique for multiple access transmission media

C. a form of TDMA in which circuit switching is used to dynamically change the channel assignments

D. All of the above

Discuss