3. The information to be communicated in a data communication system is
Correct : C. Message
4. In a network with 25 computers, which topology would require most extensive calling
Correct : B. Star
5. In a network with 25 computers, which topology would require most extensive calling
Correct : A. Mesh
6. Which topology features a point to point line configuration
Correct : D. All of above
7. A cable break in which topology stops all transmission
Correct : B. Bus
8. The OSI model consist of
Correct : C. 7 layers
9. Dialog control is the function of which layer
Correct : B. Session
10. Data unit is called a frame in
Correct : D. Data link layer
11. Communication between a computer and a keyboard involves ______________
transmission.
Correct : A. simplex
12. A television broadcast is an example of _______ transmission.
Correct : A. simplex
13. A _______ connection provides a dedicated link between two devices.
Correct : A. point-to-point
14. In a _______ connection, more than two devices can share a single link.
Correct : B. multipoint
15. In _______ transmission, the channel capacity is shared by both communicating devices
at all times.
Correct : C. full-duplex
16. In the original ARPANET, _______ were directly connected together.
Correct : A. IMPs
17. This was the first network.
Correct : D. ARPANET
18. Which organization has authority over interstate and international commerce in the
communications field?
Correct : C. FCC
19. _______ are special-interest groups that quickly test, evaluate, and standardize new
technologies.
Correct : A. Forums
20. Which agency developed standards for physical connection interfaces and electronic
signaling specifications?
Correct : A. EIA
21. _______ is the protocol suite for the current Internet.
Correct : A. TCP/IP
22. _______ refers to the structure or format of the data, meaning the order in which they are
presented.
Correct : B. Syntax
23. ________ defines how a particular pattern to be interpreted, and what action is to be
taken based on that interpretation.
Correct : A. Semantics
24. _______ refers to two characteristics: when data should be sent and how fast it can be
sent.
Correct : C. Timing
25. The_________ layer is responsible for the delivery of a message from one process to
another.
Correct : B. transport
26. The Internetworking Protocol (IP) is a ________ protocol.
Correct : D. none of the above
27. _______ is a process-to-process protocol that adds only port addresses, checksum error
control, and length information to the data from the upper layer.
Correct : B. UDP
28. __________ provides full transport layer services to applications.
Correct : A. TCP
29. The ________ address, also known as the link address, is the address of a node as defined
by its LAN or WAN.
Correct : B. physical
30. Ethernet uses a ______ physical address that is imprinted on the network interface card
(NIC).
Correct : C. 6-byte
31. Which layer links the network support layers and user support layers
Correct : C. transport layer
32. Which address is used in an internet employing the TCP/IP protocols?
Correct : D. all of the mentioned
33. Which address identifies a process on a host?
Correct : C. port address
34. Transmission data rate is decided by
Correct : B. physical layer
35. Physical layer provides
Correct : D. all of the mentioned
36. The physical layer translates logical communication requests from the ______ into
hardware specific operations.
Correct : A. data link layer
37. A single channel is shared by multiple signals by
Correct : C. multiplexing
38. Wireless transmission can be done via
Correct : D. all of the mentioned
39. In asynchronous serial communication the physical layer provides
Correct : C. both (a) and (b)
40. The physical layer is responsible for
Correct : D. all of the mentioned
41. Attenuation means
Correct : A. loss of energy
42. If r is the number of data elements carried per signal element, N is the data rate, and S is
the signal rate, then
Correct : B. S = N/r
43. NRZ L and NRZ I differ in
Correct : C. Both a and b
44. Analog to digital conversion can be done using
Correct : C. Both a and b
45. The frequency of the modulated signal is constant for the duration of one signal element, but changes for the next signal element if the data element changes. Both peak amplitude and phase remain constant for all signal elements. This is
Correct : B. FSK
46. QAM combines
Correct : C. ASK and PSK
47. Differential Manchester and multi line transmission (MLT-3) schemes differ in
Correct : C. Both a and b
48. OSI model defines an open system as
Correct : A. a set of protocols that allows any two different systems to communicate
49. 1 TeraHertz =
Correct : C. 1000000000000 Hz
50. Shannon capacity formula for noisy channel is
Correct : C. C = B Log (1 + SNR)
51. In sliding window, if the window size is 63, what is the range of sequence numbers?
Correct : A. 0 to 63
52. Regulation of the rate of transmission of data frames is known as
Correct : B. Data rate control
53. When a primary device wants to send data to a secondary device, it needs to first send _______ frame.
Correct : D. ENQ
54. Flow control is needed to prevent
Correct : C. Overflow of receiver buffer
55. A timer is set when _____________is sent.
Correct : A. Packet
56. In a Go-Back-N ARQ, if the window size is 63, what is the range of sequence numbers?
Correct : A. 0 to 63
57. In Go-Back-N ARQ, if frames 4, 5, and 6 are received successfully, the receiver may send an ACK _______ to the sender.
Correct : C. 7
58. ARQ stands for _______.
Correct : B. Automatic repeat request
59. For Stop-and-Wait ARQ, for 10 data packets sent, _______ acknowledgments are needed.
Correct : A. exactly 10
60. HDLC is an acronym for _______.
Correct : B. High-level data link control
61. Data link control deals with the design and procedures for ______ communication.
Correct : A. node-to-node
62. _______ in the data link layer separates a message from one source to a destination, or from other messages going from other sources to other destinations.
Correct : C. Framing
63. In _______ framing, there is no need for defining the boundaries of frames.
Correct : A. fixed-size
64. In ________ framing, we need a delimiter (flag) to define the boundary of two frames.
Correct : B. variable-size
65. _________framing uses two categories of protocols: character-oriented and bit-oriented.
Correct : B. Variable-size
66. In a ________ protocol, the data section of a frame is a sequence of characters.
Correct : B. character-oriented
67. In a _________ protocol, the data section of a frame is a sequence of bits.
Correct : B. bit-oriented
68. In _________ protocols, we use ________.
Correct : A. character-oriented; byte stuffing
69. Byte stuffing means adding a special byte to the data section of the frame when there is a character with the same pattern as the ______.
Correct : C. flag
70. In ________ protocols, we use ________.
Correct : C. bit-oriented; bit stuffing
71. Bit stuffing means adding an extra 0 to the data section of the frame when there is a
sequence of bits with the same pattern as the ________.
Correct : C. Flag
72. _______ control refers to a set of procedures used to restrict the amount of data that the
sender can send before waiting for acknowledgment.
Correct : A. Flow
73. ______ control refers to methods of error detection and correction.
Correct : B. Error
74. In a linear block code, the _______ of any two valid codewords creates another valid codeword
Correct : A. XORing
75. A simple parity-check code can detect __________ errors.
Correct : D. an odd-number of
76. _______codes are special linear block codes with one extra property. If a codeword is
rotated, the result is another codeword.
Correct : C. Cyclic
77. The _____of errors is more difficult than the ______.
Correct : A. correction; detection
78. In modulo-11 arithmetic, we use only the integers in the range ______, inclusive.
Correct : C. 0 to 10
79. In modulo-2 arithmetic, we use only ______.
Correct : C. 0 and 1
80. Adding 1 and 1 in modulo-2 arithmetic results in _________.
Correct : C. 0
81. Which one of the following task is not done by data link layer?
Correct : D. channel coding
82. Which sublayer of the data link layer performs data link functions that depend upon the
type of medium?
Correct : B. media access control sublayer
83. Header of a frame generally contains
Correct : D. all of the above
84. When 2 or more bits in a data unit has been changed during the transmission, the error is
called
Correct : B. burst error
85. CRC stands for
Correct : A. cyclic redundancy check
86. Which one of the following is a data link protocol?
Correct : D. all of the above
87. The technique of temporarily delaying outgoing acknowledgements so that they can be hooked onto the next outgoing data frame is called
Correct : A. piggybacking
88. The data link layer takes the packets from _____ and encapsulates them into frames for
transmission.
Correct : A. network layer
89. The maximum size of payload field in Ethernet frame is
Correct : D. 1500 bytes
90. What is inter-frame gap?
Correct : A. idle time between frames
91. Error detection at the data link level is achieved by
Correct : B. Cyclic Redundancy Code
92. "BAUD" rate means
Correct : C. The rate at which the signal changes.
93. Start and stop bits are used in serial communication for
Correct : C. Synchronization
94. Unmodulated signal coming from a transmitter is know as
Correct : B. Baseband signal
95. Maximum data rate of a channel for a noiseless 3-kHz binary channel is
Correct : B. 6000 bps
96. The ________ measures the number of lost or garbled messages as a fraction of the total sent in the sampling period.
Correct : A. Residual Error Rate.
97. In session layer, during data transfer, the data stream responsible for the "control" purpose (i.e control of the session layer itself) is
Correct : C. Capability Data
98. Which of the following is not a field in the Ethernet Message packet?
Correct : C. Pin-code
99. The Network topology that supports bi-directional links between each possible node is
Correct : D. Mesh
100. Which network has connectivity range up to 10 meters?