1. The functionalities of the presentation layerinclude
Correct : D. All of the mentioned
2. Delimiting and synchronization of data exchange is providedby
Correct : B. Session layer
3. In OSI model, when data is sent from device A to device B, the 5th layer to receive data at B is
Correct : D. Session layer
4. In TCP IP Model, when data is sent from device A to device B, the 5th layer to receive data at B is
Correct : A. Application layer
5. Which layer is used to link the network support layers and user supportlayers?
Correct : C. Transport layer
6. OSI standsfor
Correct : A. Open system interconnection
7. Which Project 802 standard provides for a collision-free protocol?
Correct : C. 802.5
8. The protocol data unit (PDU) for the application layer in the Internet stack is
Correct : C. Message
9. What is a Firewall in Computer Network?
Correct : C. A system designed to prevent unauthorized access
10. Which of the following services is not provided by wireless access point in
802.11 WLAN?
Correct : C. Error correction
11. Bridge works in which layer of the OSI model?
Correct : D. Data link layer
12. Why IP Protocol is considered as unreliable?
Correct : D. All of the above
13. What are the uses of subnetting ?
Correct : A. It divides one large network into several smaller ones
14. The Internet is an example of
Correct : C. Packet switched network
15. What does protocol defines?
Correct : D. All of above
16. What is the use of Ping command?
Correct : A. To test a device on the network is reachable
17. What is the Demilitarized Zone?
Correct : A. The area between firewall & connection to an external network
18. The combination of an IP address and a port number is known as.
Correct : B. socket address
19. Which of the following is reliable communication?
Correct : A. TCP
20. What is the size of Host bits in Class B of IP address?
Correct : C. 16
21. Which of the following is not associated with the session layer?
Correct : C. Semantics of the information transmitted
22. The Internet Control Message Protocol (ICMP)
Correct : A. allows gateways to send error a control messages to other gateways or hosts
23. Your company has a LAN in its downtown office and has now set up aLAN 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 correct answer.
Correct : D. Router
24. Which of the following TCP/IP protocol is used for transferringelectronic
mail messages from one machine to another?
Correct : C. SMTP
25. Which of the following device is used to connect two systems, especiallyif
the systems use different protocols?
Correct : C. gateway
26. can detect burst error of length less than or equal to degree of the
polynomial and detects burst errors that affect odd number of bits.
Correct : B. CRC
27. The PSTN is an example of a............................. network.
Correct : B. circuit switched
28. When and where RARP is used intentionally or effectively?
Correct : A. At the time of network booting where no space to store IP address (or diskless network) for address resolution.
29. Which one of the following routing algorithm can be used for network layer
design?
Correct : D. all of the mentioned
30. A subset of a network that includes all the routers but contains no loopsis
called:
Correct : A. spanning tree
31. ICMP is primarily used for:
Correct : A. error and diagnostic functions
32. User datagram protocol is called connectionless because:
Correct : A. all UDP packets are treated independently by transport layer
33. An endpoint of an inter-process communication flow across a computer
network is called:
Correct : A. socket
34. A is a TCP name for a transport service access point.
Correct : A. port
35. Which one of the following is a transport layer protocol?
Correct : A. stream control transmission protocol
36. Physical layer provides:
Correct : D. all of the mentioned
37. The translates internet domain and host names to IP address.
Correct : A. domain name system
38. When displaying a web page, the application layer uses the:
Correct : A. HTTP protocol
39. This is a time-sensitive service:
Correct : D. Internet telephony
40. Packet sniffers involve:
Correct : B. Passive receiver
41. Identify the incorrect statement:
Correct : C. FTP sends its control information in-band
42. If 5 files are transferred from server A to client B in the same session. The
number of TCP connection between A and B is:
Correct : D. 6
43. Find the FTP reply whose message is wrongly matched:
Correct : D. 452 – Can’t open data connection
44. In an Ethernet local area network, which one of the following statementsis
TRUE?
Correct : D. The exponential back off mechanism reduces the probability of collision on retransmissions
45. The first Network:
Correct : D. ARPANET
46. Which organization has authority over interstate and international commerce
in the communications field?
Correct : C. FCC
47. Baud rate is:
Correct : A. number of signal changes per second
48. The slowest transmission speeds are those of
Correct : B. Twisted pair wire
49. The performance of a data communication network depends on
Correct : D. All of the above
50. Which of the following to keep track of the individual units of data (called packets) that a message is divided into for efficient routing through the Internet.
Correct : D. Transmission Control Protocol/Internet Protocol (TCP/IP)
51. The process of keeping addresses in memory for future use is called
Correct : C. Caching
52. A small network making up the Internet and also having a small numbers of
computers within it is called
Correct : C. Subdomain
53. If a file consisting of 50,000 characters takes 40 seconds to send, then the
data rate is .
Correct : D. 10 kbps
54. In CRC there is no error if the remainder at the receiver is .
Correct : B. zero
55. Internet-like networks within an enterprise.
Correct : A. Intranets
56. Sending a file from your personal computer's primary memory or disk to
another computer is called
Correct : A. uploading
57. FDDI is a
Correct : A. ring network
58. Which address is the loopback address?
Correct : C. 127.0.0.1
59. A modulator converts a signal to a(n) signal.
Correct : C. analog; digital
60. The birthplace of the World Wide Web is considered to be
Correct : B. CERN
61. What is the port number for HTTP?
Correct : C. 80
62. The communication mode that supports data in both directions at the same
time is
Correct : C. full-duplex
63. The basic Ethernet design does not provide
Correct : C. automatic retransmission of a message
64. What does the acronym ISDN stand for?
Correct : B. Integrated Services Digital Network
65. ASK, PSK, FSK, and QAM are examples of encoding.
Correct : B. digital-to-analog
66. Who invented the modem?
Correct : B. AT & T Information Systems, USA
67. With an IP address of 201.142.23.12, what is your default subnetmask?
Correct : D. 255.255.255.0
68. Which utility is an all-purpose tool for troubleshooting TCP/IP problems?
Correct : C. PING
69. Which Layer is Responsible for Congestion Control?
Correct : C. Transport Layer
70. Pure ALOHA has a maximum throughput of -----------
Correct : B. 18.4 %
71. Which of these is a feature of hubs?
Correct : C. All lines coming into a Hub must operate at a same speed.
72. DSL stands for
Correct : D. digital subscriber lines
73. Which of the following is a MAC address?
Correct : D. 01:A5: BB: A7: FF: 60
74. The main difference between TCP and UDP is
Correct : C. UDP is a datagram whereas TCP is a connection oriented service
75. What operates in the Data Link and the Network layer?
Correct : C. Brouter
76. Which file transfer protocol uses UDP?
Correct : C. TFTP
77. Which of the following network access standard is used for connecting
stations to a circuit-switched network?
Correct : B. X.21
78. In OSI model, which of the following layer provides error-free delivery of
data?
Correct : C. transport
79. To avoid transmission errors, a check figure is calculated by the
Correct : C. both (a) and (b)
80. What is the first octet range for a class A IP address?
Correct : A. 1 - 126
81. CSMA (Carrier Sense Multiple Access) is
Correct : B. a method access control technique for multiple-access transmission media.
82. What is the first octet range for a class B IP address?
Correct : D. 128 - 191
83. ARP (Address Resolution Protocol) is
Correct : A. a TCP/IP protocol used to dynamically bind a high level IP Address to a lowlevel physical hardware address
84. The 802.5 standard implements a way for preventing collisions on the
network. How are collisions prevented when using this standard?
Correct : B. Token passing
85. Terminals are required for
Correct : D. real time, timesharing, and message switching
86. What OSI layer handles logical address to logical name resolution?
Correct : A. Transport
87. Consider different activities related to email.
m1:Send an email from a mail client to mail server m2:Download an email from mailbox server to a mail client m3:Checking email in a web browser Which is the applicable level protocol user in each activity?
Correct : C. m1:SMTP, m2:POP, m3:HTTP
88. One of the header fields in an IP datagram is the Time to Live (TTL) field. Which of the following statements best explains the need for this field?
Correct : D. It can be used to prevent packet looping
89. Which of the following system calls results in the sending of SYNpackets?
Correct : D. connect
90. In the slow start phase of the TCP congestion control algorithm, the size of
the congestion window
Correct : D. increases exponentially
91. What is the maximum size of data that the application layer can pass on to
the TCP layer below?
Correct : A. Any size
92. A computer on a 10Mbps network is regulated by a token bucket. The token bucket is filled at a rate of 2Mbps. It is initially filled to capacity with 16Megabits. What is the maximum duration for which the computer can transmit at the full 10Mbps?
Correct : B. 2 seconds
93. In Ethernet when Manchester encoding is used, the bit rate is:
Correct : A. Half the baud rate.
94. Station A needs to send a message consisting of 9 packets to Station B using a sliding window (window size 3) and go-back-n error control strategy. All packets are ready and immediately available for transmission. If every 5th packet that A transmits gets lost (but no acks from B ever get lost), then what isthe number of packets that A will transmit for sending the message to B?
Correct : C. 16
95. Determine the maximum length of the cable (in km) for transmitting data at a rate of 500 Mbps in an Ethernet LAN with frames of size 10,000 bits. Assume the signal speed in the cable to be 2,00,000 km/s.
Correct : B. 2
96. Let G(x) be the generator polynomial used for CRC checking. What is the condition that should be satisfied by G(x) to detect odd number of bits in error?
Correct : C. 1+x is a factor of G(x)
97. In serial data transmission, every byte of data is padded with a ‘0’ in the
beginning and one or two ‘1’ s at the end of byte because
Correct : A. Receiver is to be synchronized for byte reception
98. Which one of the following statements is FALSE?
Correct : B. Packet switching results in less variation in delay than circuitswitching.
99. Which of the following statements is FALSE regarding a bridge?
Correct : D. Bridge reduces broadcast domain
100. In a packet switching network, if the message size is 48 bytes and each
packet contains a header of 3 bytes. If 24 packets are required to transmit the message, the packet size is .