MCQs

 

Unit I 

 

1. The data link layer provides ________ delivery.

a. host-to-host

b. port-to-port

c. process-to-process

d. hop-to-hop 

 

2. For n devices in a network and duplex mode transmission facility, the number

of cable links required for a mesh topology is –

a. n2

b. 2n

c. n(n-1)/2

d. n(n-1) 

 

3. The layer responsible for encryption technique in OSI model is –

a. network

b. presentation

c. data link

d. session 

 

4. Switches function in which layer(s) of OSI model?

a. physical

b. data link

c. network

d. both a and b 

 

5. Which topology requires a multipoint connection?

a. mesh

b. star

c. ring

d. bus 

 

6. The transport layer provides _________ delivery.

a. bit-to-signal transmission

b. bit synchronization

c. process-to-process

d. hop-to-hop

 

7. The topology with highest reliability is–

a. bus topology

b. star topology

c. mesh topology

d. ring topology

 

8. The dedicated physical layer devices are –

a. Hub & Switch

b. Hub & multiplexer

c. ATM switch & MUX

d. Repeater & Router 

 

9. Advantage of layering includes –

a. multi-vendor integration

b. data hiding & encapsulation

c. easy testing

d. all of these 

 

10. A network which is used for sharing data, software and hardware among small number

of users owning microcomputers is called

a. WAN

b. LAN

c. MAN

d. VAN 

 

11. Which topology requires a central controller or hub?

a. Mesh

b. star

c. ring

d. bus 

 

12. Flow control in OSI reference model is performed in –

a. Data link layer

b. Network layer 

c. Session layer

d. Application layer 

 

13. Open Source Interconnection is developed by _____ and has ____ layers.

a. IEEE, 7

b. ISI, 5

c. ISO, 7

d. ISI, 7 

 

14. Method of communication in which transmission takes place in both

directions, but only in one direction at a time, is called

a. Simplex

b. full-duplex

c. four-wire circuit

d. half-duplex 

 

15. Communication between a computer and a keyboard involves –

a. Simplex

b. Half-duplex

c. Duplex

d. Automatic 

 

16. The key elements of a protocol are –

a. syntax

b. semantics

c. timing

d. all of these 

 

17. Repeaters function in which layer(s)?

a. physical

b. data link

c. network

d. both a and b 

 

18. Bridges/Switches function in which layer(s)?

a. physical

b. data link

c. network

d. both a and b 

 

19. Routers function in which layers?

a. physical and data link

b. physical, data link and network

c. data link and network

d. network and transport

 

20. Gateways in OSI model can function all the way up to –

a. transport layer

b. session layer

c. presentation layer

d. application layer 

 

21. Which of the following allows devices on one network to communicate with devices

on another network?

a. Multiplexer

b. Gateway

c. Switch

d. Modem 

 

22. Different computers are connected to a LAN by a cable and –

a. Modem

b. interface card

c. special wires

d. telephone lines 

 

Unit II

 

23. The extended ASCII is of _____ bit size and can represent up to ______ characters.

a. 7 bit, 128

b. 8 bit, 128

c. 8 bit, 256

d. 7 bit, 256

 

 24. Manchester code is a–

a. Non-return to zero code

b. Polar code

c. Bipolar code

d. both a and c 

 

25. Baud means –

a. number of bits transmitted per unit time

b. number of bytes transmitted per unit time

c. rate at which the signal changes

d. none of these 

 

26. If the maximum value of a signal is 31 and minimum value is -32, how many bits are

used for coding?

a. 4

b. 5

c. 6

d. 8 

 

27. A telephone network is an example of _______ network.

a. Packet-switched

b. Circuit-switched

c. Message-switched

d. None of the above 

 

28. BNC connectors are used by ________ cable

a. UTP

b. STP

c. Coaxial

d. Fiber-optic 

 

29. In an optical fiber, the inner core is _______ the cladding

a. denser than

b. less dense than

c. the same density as

d. another name for 

 

30. The RJ45 is a connector used in case of

a. 10Base2

b. 10Base5

c. 10BaseT

d. 10BaseF 

 

31. The number of times a signal changes value per second is called the ___________ .

a. Bit rate

b. Baud rate

c. frequency rate

d. Bit interval 

 

32. In Ethernet when Manchester encoding is used, the bit rate is

a. Half the baud rates

b. Twice the baud rate

c. Same as the baud rated

d. none of these 

 

33. Different computers are connected to a LAN by a cable and –

a. Modem

b. NIC

c. special wires

d. telephone lines 

 

34. Blue-tooth uses ______ to communicate between two devices

a. Radio wave

b. Microwave

c. Infrared

d. Satellite 

 

35. In a network with 25 computers, which topology would require the most extensive

cabling?

a. Star

b. Bus 

c. Ring

d. Mesh

 

36. All the packets of a message follow the same channels of a path in

a. packet switching

b. circuit switching

c. message switching

d. virtual circuit 

 

37. The bit rate of a signal is 40,000 hertz. If a signal element encodes 4 bits, the baud rate

will be

a. 40000

b. 10000

c. 20000

d. 1000 

 

38. What is the bandwidth of a signal whose lower frequency is 20 KHz and upper

frequency is 60 KHz?

a. 80 KHz

b. 3 KHz

c. 1200 KHz

d. 40 KHz

 

Unit III

 

39. Bit Stuffing inserts a 0 bit after ________ consecutive 1 bits in the message data.

a. 4

b. 5

c. 6

d. 7

 

40. The 1-persistent CSMA / CD is a special case of the p-persistent approach with p =

a. 0.5

b. 0.1

c. 1.0

d. 100 

  

41. Pure ALOHA has a maximum efficiency of

a. 18%

b. 37%

c. 10%

d. None of these 

 

42. In the _____ random-access method there is no collision

a. ALOHA

b. CSMA / CD

c. CSMA / CA

d. Token passing 

 

43. How much channel throughput of Slotted ALOHA will be in comparison to Pure

ALOHA?

a. Same

b. Double

c. Three times

d. None of these 

 

44. What is the Hamming distance between 11100110 and 10100011?

a. 2

b. 3

c. 4

d. 5 

 

45. An Ethernet has 38 bytes of data. How many bytes padding should be added?

a. 12

b. 8

c. 26

d. 46 

 

46. In Ethernet CSMA/CD, the special bit sequence transmitted by media access

management collision handling is called as

a. Preamble

b. Post amble

c. Jam

d. Flag 

 

47. The monitor station in what standard ensures that one and only one token is

circulating?

a. 802.3

b. 802.4

c. 802.5

d. 802.11 

 

48. Flow control is used to prevent

a. overflow of sender buffer

b. overflow of receiver

c. collision between sender and receiver

d. underflow of sender and receiver 

 

49. If the ASCII “m” character is received as an “n” character, this is known as

a. single-bit error

b. burst error

c. character error

d. byte error 

 

50. A single bit error is more likely in a _____ transmission while a burst error is more

likely in a ______ transmission.

a. Serial; parallel

b. Parallel; serial

c. Serial; multiplexed

d. Duplex; parallel 

 

51. Which of the following is an error detection method?

a. Multiplexing

b. Redundancy

c. Reciprocity

d. Conditioning 

 

52. Which type of redundancy check do the upper layers primarily use?

a. VRC

b. CRC

c. LRC

d. Checksum 

 

CRC

Cyclic redundancy check

 

53. Which method can detect all single-bit error

a. CRC

b. VRC

c. LRC

d. All of the above 

VRC can detect single bit errors. LRC can detect burst errors.

 

54. A sender has a sliding window of size 15. The first 15 frames are sent. How many

frames are in the window now?

a. 0

b. 1

c. 14

d. 15

 

55. A sender has a sliding window of size 15. The first 10 frames are sent. How many

frames are in the window now?

a. 4

b. 5

c. 6

d. 10 

 

56. The receiver’s window in a sliding window protocol expands when

a. An ACK is received

b. An ACK is sent

c. A frame is sent

d. A frame is received 

 

57. The stop-and-wait flow control method is the same as the sliding window method with

a window size of ______

a. 0

b. 1

c. 2

d. None of the above 

 

58. Flow control is mainly a function of ________ layer

a. Application

b. Presentation

c. Session

d. Data link 

 

59. Stop-and wait is a _______ technique

a. Line discipline

b. Flow control

c. Error control

d. Session management 

 

60. Sliding window is a _________ technique

a. Line discipline

b. Flow control

c. Error control

d. Session management

 

61. In the sliding window method of flow control, the sender may send ____ at a time

a. Several frame

b. Only one frame

c. A set number of frame

d. Two frame 

 

62. In a stop-and-wait method of flow control, after the receiver receives a data frame,

________ frame can be sent

a. An ACK

b. A NAK

c. An EOT

d. (a) or (b) 

 If the ACK is not received, it re-transmits the previous packet again.

 

63. What is the main disadvantage of stop-and-wait flow control?

a. Unreliable

b. Inefficient

c. Attenuation

d. Dropped packets 

 

64. In the sliding window method of flow control, the sender window _____ size when

frames are sent.

a. Increases in

b. Decrease in

c. Expands in

d. Remains its original 

 

65. In the sliding window method of flow control, the sender window _____ size when an

ACK is received

a. Increase in

b. Decrease in

c. Doubles in

d. Remains its original 

 

66. In a LAN defined by project 802, the _________ sub layer of the data link layer is

non-architecture specific

a. CSMA

b. MAC

c. LLC

d. (a) and (b) 

 

67. IEEE 802.1 is concerned with ________ issues in LANs and MANs

a. Error handling

b. Networking

c. Internetworking

d. Flow control 

 

68. The _______ sub layer, as specified in Project 802, is LAN specific and deals with

contention issues.

a. CSMA

b. MAC

c. LLC

d. (a) and (b) 

 

69. Ethernet, Token Ring and token Bus are all different types of 

a. LANs

b. MANs

c. WANs

d. VANs

 

70. The _______ is the data unit at the LLC level

a. HDLC

b. PDU

c. SSAP

d. MAC 

 

71. Which of the following is an IEEE Project 802 standard?

a. Ethernet

b. Token Ring

c. Token Bus

d. All of the above 

 

72. _______ signal is digital

a. A baseband

b. A broadband

c. An Ethernet

d. None of the above 

 

73. ________ signal is analog

a. A baseband

b. A broadband

c. An Ethernet

d. None of the above 

 

74. Token Bus is physically configured like ______

a. Ethernet

b. Token Ring

c. FDDI

d. All of the above 

 

75. Token Bus operates under a collision-free environment similar to ______

a. Ethernet

b. Token Ring

c. CSMA/CD

d. All of the above 

 

76. The _____ field in a token Ring frame is equivalent to the HDLC flag field

a. SD

b. AC

c. FC

d. FS 

 

77. A Token Ring frame can be identified as a token frame by a bit in the field

a. SD

b. AC

c. FC

d. ED 

 

78. In Token Ring, the _______ sets the bits in the frame status field to indicate that the

frame has been copied.

a. Sender

b. Receiver

c. Monitor

d. (a) and (b) 

 

79. The Token Ring AC field contains _______ information

a. Priority

b. Frame type

c. Reservation

d. All of the above 

 

80. In a Token Ring LAN, a frame is _______ at each station

a. Examined

b. Regenerated

c. Encapsulated

d. (a) and (b) 

 

81. A multistation access unit is most often used in ______ LAN

a. An Ethernet

b. A Token Ring 

c. An FDDI

d. (a) and (b)

 

Unit IV

 

82. A bridge has access to which address of a station on the same network?

a. physical

b. network

c. service access point

d. all of the above 

 

83. An IPv6 address consists of _________ bits.

a. 48

b. 16

c. 32

d. 128 

 

84. Identify the IP address in the class B–

a. 125.123.123.2

b. 191.23.21.54

c. 192.128.32.56

d. 10.14.12.34 

 

85. Routers function in which layer(s)?

a. physical

b. data link

c. network

d. all of these 

 

86. IP address in the class C is given by –

a. 125.123.123.2

b. 191.23.21.54

c. 192.128.32.56

d. 10.14.12.34 

 

87. ARP is a –

a. TCP/IP protocol used to dynamically bind a high level IP address to a low level physical

hardware address

b. TCP/IP high level protocols for transferring files from one machine to another

c. Protocol used to monitor computers

d. Protocol that handles error and control messages 

 

88. Which of the following is NOT an IPv6 address?

a. anycast

b. multicast

c. broadcast

d. unicast 

 

89. The network layer provides __________ delivery.

a. host-to-host

b. port-to-port

c. process-to-process

d. hop-to-hop

 

90. Maximum size of the data portion of the IP datagram is

a. 65515 bytes

b. 65555 bytes

c. 65535 bytes

d. none of these 

 

91. IP address can be used to specify a broadcast and map to hardware broadcast

if available. By conversion broadcast address has hosted with bits

a. all 0

b. all 1

c. alternate 0 and 1

d. alternate 1 and 0 

 

92. Which of the following is an interior routing protocol?

a. RIP(Routing Information Protocol)

b. OSPF(Open Shortest Path First )

c. BGP(Border Gateway Protocol)

d. both a and b 

 

93. A station in a network forward incoming packets by placing them on its shortest output

queue. What routing algorithm is being used?

a. Hot Potato routing

b. Flooding

c. Static routing

d. Delta routing 

 

94. Which routing algorithm requires more traffic between routers for set-up and

updating?

a. Distance vector

b. Link state

c. Dijkstra

d. Vector link 

 

95. Identify the class of IP address 199.1.2.3.

a. A

b. B

c. C

d. D 

 

96. A subnet mask in class A has fourteen 1s. How many subnets does it define?

a. 32

b. 8

c. 64

d. 128

 

97. Class _______ has the greatest number of hosts per given network address.

a. A

b. B

c. C

d. D 

 

98. In ________ routing, the full IP address of a destination is given in the routing table.

a. Next-hop

b. Network-specific

c. Host-specific

d. Default 

 

99. In ________ routing, the destination address is a network address in the routing table.

a. Next-hop

b. Network-specific

c. Host-specific

d. Default 

 

100. What is the hostid of the IP address 114.34.2.8

a. 114.34

b. 114.34.2

c. 2.8

d. 34.2.8

 

101. You are working with a network that is 172.16.0.0 and would like to support 600 hosts

per subnet. What subnet mask should you use?

a. 255.255.192.0

b. 255.255.224.0

c. 255.255.248.0

d. 255.255.252.0 

 

102. What is the loopback address?

a. 127.0.0.1

b. 255.255.0.0

c. 255.0.0.0

d. 255.0.0.0 

 

103. What part of 192.168.10.51 is the Network ID, assuming a default subnet mask?

a. 192

b. 192.168.10

c. 0.0.0.5

d. 51 

 

104. How many bits of internet address is assigned to each host on a TCP/IP internet which

is used in all communications with the host?

a. 16 - bits

b. 32 - bits

c. 48 - bits

d. 64 - bits 

 

105. Which of the following is the address of the router?

a. The IP address

b. The TCP address

c. The subnet mask

d. The default gateway 

 

106. What is the first octet range for a class C IP address?

a. 192 - 255

b. 192 - 223

c. 192 - 226

d. 128 - 191 

 

107. How many class A, B, and C network IDs can exist?

a. 2,113,658

b. 16,382

c. 126

d. 128 

 

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

a. 127.0.0.1

b. 255.0.0.0

c. 255.255.255.0.0

d. 255.255.255.0 

 

109. With an IP address of 201.142.23.12, what is your default subnet mask?

a. 0.0.0.0

b. 255.0.0.0

c. 255.255.0.0

d. 255.255.255.0 

 

Unit V

 

110. UDP is

a. reliable and connection oriented

b. unreliable and connection oriented

c. unreliable and connectionless

d. reliable and connectionless 

 

111. The ______ layer ensures end-to-end reliable data transmission.

a. Network

b. Physical

c. Data link

d. Transport 

 

112. ________ addresses on headers change as a packet moves from network to network

but the ________ do not.

a. Logical; port

b. Logical; network

c. Logical; physical

d. Physical; logical 

 

113. The ______ layer lies between the network layer and the session layer

a. Physical

b. Data link

c. Transport

d. application 

 

114. The ______ layer is responsible for source-to-destination delivery of the entire

message

a. Physical

b. Data link

c. Transport

d. Network 

 

115. A _______ address identifies a process running on a computer

a. Logical

b. Physical

c. Network

d. Service-point 

 

116. The header added by the transport layer to the packet coming from the upper layer

includes the _______ address

a. Logical

b. Service-point

c. Physical

d. network 

 

117. Segmentation and reassembly are functions of the _______ layer

a. Physical

b. Data link

c. Transport

d. Network 

 

118. In a connection-oriented exchange the first phase is _______ between the transport

layers of the source and destination

a. Connection establishment

b. Exchange of data packets

c. Connection termination

d. None of the above 

 

119. In a connection-oriented exchange the last phase after all the data packets are

transferred is

a. Connection establishment

b. Flow control

c. Connection termination

d. None of the above 

 

120. The assignment of sequence numbers to packets of message is a function of the

______ layer 

a. Physical

b. Data link

c. Transport

d. network 

 

121. The reassembly of packets into the original message is a function of the _______ layer

a. Physical

b. Data link

c. Transport

d. Network 

 

122. The division of a message into packets is a function of the ______ layer

a. Physical

b. Data link

c. Transport

d. Network

 

*********END***** 

 

 PART -2

Which one of the following task is not done by data link layer?
a.	framing
b.	error control
c.	flow control
d.	channel coding
	Answer:channel coding

 The IETF standards documents are called ________
a) RFC
b) RCF
c) ID
d) DFC
=> a
RFC stands for Request For Comments and they are documents that describe methods, behaviors, research, or innovations applicable to the working of the Internet.

 

Which one of the following algorithm is not used for congestion control?
a) traffic aware routing
b) admission control
c) load shedding
d) routing information protocol =>D

 The network layer is concerned with __________ of data.
a) bits
b) frames
c) packets
d) bytes =>C

Header of a frame generally contains ______________
a) synchronization bytes
b) addresses
c) frame identifier
d) all of the mentioned  => D

The technique of temporarily delaying outgoing acknowledgements so that they can be hooked onto the next outgoing data frame is called ____________
a) piggybacking
b) cyclic redundancy check
c) fletcher’s checksum
d) parity check => A

The data link layer takes the packets from _________ and encapsulates them into frames for transmission.
a) network layer
b) physical layer
c) transport layer
d) application layer  => A

A 4 byte IP address consists of __________
a) only network address
b) only host address
c) network address & host address
d) network address & MAC address=> C

The network layer responds to request from which layer?
a) Transport layer
b) Data layer
c) Application layer
d) Session layer

A

 

The network layer contains which hardware device?
a) Routers, Bridges
b) Bridges only
c) Bridges and switches
d) Routers, Bridges and Switches

D

 

 In the layer hierarchy as the data packet moves from the upper to the lower layers, headers are ___________
a) Added
b) Removed
c) Rearranged
d) Modified
=> A
Each layer adds its own header to the packet from the previous layer. For example, in the Internet layer, the IP header is added over the TCP header on the data packet that came from the transport layer.


The structure or format of data is called ___________
a) Syntax
b) Semantics
c) Struct
d) Formatting
=> A
The structure and format of data are defined using syntax. Semantics defines how a particular pattern to be interpreted, and what action is to be taken based on that interpretation. In programming languages, syntax of the instructions plays a vital role in designing of the program.

Communication between a computer and a keyboard involves ______________ transmission.
a) Automatic
b) Half-duplex
c) Full-duplex
d) Simplex
=> D

The first Network was called ________
a) CNNET
b) NSFNET
c) ASAPNET
d) ARPANET
=> d
ARPANET stands for Advanced Research Projects Agency Networks. It was the first network to be implemented which used the TCP/IP protocol in the year 1969.

Layer 3

Layer 3 of the OSI Model: Network Layer

A _______ is the physical path over which a message travels.
a) Path
b) Medium
c) Protocol
d) Route
=> b
Messages travel from sender to receiver via a physical path called the medium using a set of methods/rules called protocol. Mediums can be guided (wired) or unguided (wireless).


Which organization has authority over interstate and international commerce in the communications field?
a) ITU-T
b) IEEE
c) FCC
d) ISOC
=> c
FCC is the abbreviation for Federal Communications Commission. FCC is responsible for regulating all interstate communications originating or terminating in USA. It was founded in the year 1934.

ICMP IS  PRIMARILY USED FOR

addressing         None of these         forwarding       error and diagnostic functions(ANS)

 ddl stands for in computer network

Datagram Delivery Protocol

Packets will be transferred in how many types?
a) 5 types
b) 4 types
c) 2 types
d) 3 types

=> 3

The Internet Control Message Protocol (ICMP)

 
Which of this is not a network edge device?
a) PC
b) Smartphones
c) Servers
d) Switch
=> d
Network edge devices refer to host systems, which can host applications like web browser. A switch can’t operate as a host, but as a central device which can be used to manage network communication.


A _________ set of rules that governs data communication.
a) Protocols
b) Standards
c) RFCs
d) Servers
=> a
 In communications, a protocol refers to a set of rules and regulations that allow a network of nodes to transmit and receive information. Each layer in the network model has a protocol set, for example, the transport layer has TCP and UDP protocols.


Three or more devices share a link in ________ connection.
a) Unipoint
b) Multipoint
c) Point to point
d) Simplex
=> b
A multipoint communication is established when three or many network nodes are connected to each other. Frame relay, Ethernet and ATM are some examples of multipoint connections.


When collection of various computers seems a single coherent system to its client, then it is called _________
a) computer network
b) distributed system
c) networking system
d) mail system
=> b
A Computer network is defined as a collection of interconnected computers which uses a single technology for connection.
A distributed system is also the same as computer network but the main difference is that the whole collection of computers appears to its users as a single coherent system.
Example:- World wide web

6. Multidestination routing
a) is same as broadcast routing
b) contains the list of all destinations
c) data is not sent by packets
d) none of the mentioned
View Answer

Answer: c

Two devices are in network if __________
a) a process in one device is able to exchange information with a process in another device
b) a process is running on both devices
c) PIDs of the processes running of different devices are same
d) a process is active and another is inactive
=> a
 A computer network, or data network, is a digital telecommunications network which allows nodes to share resources. In computer networks, computing devices exchange data with each other using connections between nodes. The nodes have certain processes which enable them to share a specific type of data using a distinct protocol.


Which of the following computer networks is built on the top of another network?
a) prior network
b) chief network
c) prime network
d) overlay network
=> d
An overlay network is a computer network that is built on top of another network. Some examples of an overlay network are Virtual Private Networks (VPN) and Peer-to-Peer Networks (P2P).


In computer network nodes are _________
a) the computer that originates the data
b) the computer that routes the data
c) the computer that terminates the data
d) all of the mentioned
=>In a computer network, a node can be anything that is capable of sending data or receiving data or even routing the data to its destination. Routers, Computers and Smartphones are some examples of network nodes.


Communication channel is shared by all the machines on the network in ________
a) broadcast network
b) unicast network
c) multicast network
d) anycast network
=> a
 In a broadcast network, information is sent to all stations in a network whereas in a multicast network the data or information is sent to a group of stations in the network. In unicast network, information is sent to only one specific station. The broadcast address of the network is the last assigned address of the network.


Bluetooth is an example of __________
a) personal area network
b) local area network
c) virtual private network
d) wide area network
=> a
Bluetooth is a wireless technology used to create a wireless personal area network for data transfer up to a distance of 10 meters. It operates on 2.45 GHz frequency band for transmission.


A __________ is a device that forwards packets between networks by processing the routing information included in the packet.
a) bridge
b) firewall
c) router
d) hub
=> c
A router is a networking device that forwards data packets between computer networks. Routers perform the traffic directing functions on the Internet. They make use of routing protocols like RIP to find the cheapest path to the destination.


. A list of protocols used by a system, one protocol per layer, is called ________
a) protocol architecture
b) protocol stack
c) protocol suite
d) protocol system
=> b
A protocol stack refers to a group of protocols that are running concurrently that are employed for the implementation of network protocol suite. Each layer in the network model has to use one specific protocol from the protocol stack.


Network congestion occurs _________
a) in case of traffic overloading
b) when a system terminates
c) when connection between two nodes terminates
d) in case of transfer failure
=> a
Network congestion occurs when traffic in the network is more than the network could handle. To avoid network congestion, the network management uses various open-loop and closed-loop congestion control techniques.


 Which of the following networks extends a private network across public networks?
a) local area network
b) virtual private network
c) enterprise private network
d) storage area network
=> b
A virtual private network extends a private network across a public network, and enables users to send and receive data across shared or public networks as if their computing devices were directly connected to the private network.VPN provides enhanced security and online anonymity to users on the internet. It is also used to unblock websites which are unavailable in certain regions.