1.

Transport layer aggregates data from different applications into a single stream
before passing it to ____________
a) network layer
b) data link layer
c) application layer
d) physical layer

2. Which of the following are transport layer protocols used in networking?

a) TCP and FTP
b) UDP and HTTP
c) TCP and UDP
d) HTTP and FTP

3. User datagram protocol is called connectionless because _____________

a) all UDP packets are treated independently by transport layer
b) it sends data as a stream of related packets
c) it is received in the same order as sent order
d) it sends data very quickly

4. Transmission control protocol ___________

a) is a connection-oriented protocol
b) uses a three way handshake to establish a connection
c) receives data from application as a single stream
d) all of the mentioned

5. An endpoint of an inter-process communication flow across a computer network is

called __________
a) socket
b) pipe
c) port
d) machine

6. Socket-style API for windows is called ____________

a) wsock
b) winsock
c) wins
d) sockwi
7. Which one of the following is a version of UDP with congestion control?
a) DatagramCongestion Control Protocol
b) Stream Control Transmission Protocol
c) Structured Stream Transport
d) User Congestion Control Protocol

8. A _____ is a TCP name for a transport service access point.

a) port
b) pipe
c) node
d) protocol

9. Transport layer protocols deals with ____________

a) application to application communication
b) process to process communication
c) node to node communication
d) man to man communication

10. Which of the following is a transport layer protocol?

a) stream control transmission protocol
b) internet control message protocol
c) neighbor discovery protocol
d) dynamic host configuration protocol

11. The transport layer protocols used for real time multimedia, file transfer, DNS and
email, respectively are:
a) TCP, UDP, UDP and TCP
b) UDP, TCP, TCP and UDP
c) UDP, TCP, UDP and TCP
d) TCP, UDP, TCP and UDP

12. Which of the following transport layer protocols is used to support electronic mail?
a) SMTP
b) IP
c) TCP
d) UDP
13. A layer-4 firewall (a device that can look at all protocol headers up to the transport
layer) CANNOT
a) Block entire HTTP traffic during 9:00PM and 5:00 AM
b) Block all ICMP traffic
c) Stop incoming traffic from a specific IP address but allow outgoing traffic to the same IP
address
d) Block TCP traffic from a specific user on a multi-user system during 9:00PM and 5:00AM

14. Which of the following system calls results in the sending of SYN packets?
a) Socket
b) Bind
c) Listen
d) Connect

15. In the slow start phase of the TCP congestion control algorithm, the size of the
congestion window
a) Does not increase
b) Increases linearly
c) Increasesquadratically
d) Increases exponentially

16. Which one of the following uses UDP as the transport protocol?
a) HTTP
b) Telnet
c) DNS
d) SMTP

17. Packets of the same session may be routed through different paths in
a) TCP, but not UDP
b) TCP and UDP
c) UDP, but not TCP
d) Neither TCP, nor UDP

18. The maximum window size for data transmission using the selective reject protocol
with n-bit frame sequence numbers is:
a) 2^n
b) 2^(n-1)
c) 2^n – 1
d) 2^(n-2)
19. Which of the following functionalities must be implemented by a transport protocol
over and above the network protocol?
a) Recovery from packet losses
b) Detection of duplicate packets
c) Packet delivery in the correct order
d) End to end connectivity

20. Which of the following is NOT true about User Datagram Protocol in transport
layer?
a) Works well in unidirectional communication, suitable for broadcast information.
b) It does three way handshake before sending datagrams
c) It provides datagrams, suitable for modeling other protocols such as in IP tunneling or
Remote Procedure Call and the Network File System
d) The lack of retransmission delays makes it suitable for real-time applications

21. Suppose two hosts use a TCP connection to transfer a large file. Which of the
following statements is/are False with respect to the TCP connection?
1. If the sequence number of a segment is m, then the sequence
number of the subsequent segment is always m+1.
2. If the estimated round trip time at any given point of time
is t sec, the value of the retransmission timeout is always
set to greater than or equal to t sec.
3. The size of the advertised window never changes during the
course of the TCP connection.
4. The number of unacknowledged bytes at the sender is always
less than or equal to the advertised window
a)3 only
b) 1 and 3 only
c) 1 and 4 only
d) 2 and 4 only

22. Identify the correct order in which a server process must invoke the function calls
accept, bind, listen, and recv according to UNIX socket API.
a) listen, accept, bind recv
b) bind, listen, accept, recv
c) bind, accept, listen, recv
d) accept, listen, bind, recv

23. Consider the following statements.

I. TCP connections are full duplex.
II. TCP has no option for selective acknowledgment
III. TCP connections are message streams.
a) Only I is correct
b) Only I and II are correct
c) Only II and III are correct
d) All of I, II and III are correct

24. Consider the following statements about the timeout value used in TCP.
i. The timeout value is set to the RTT (Round Trip Time) measured during TCP
connection establishment for the entire duration of the connection.
ii. Appropriate RTT estimation algorithm is used to set the timeout value of a TCP
connection.
iii. Timeout value is set to twice the propagation delay from the sender to the receiver.
Which of the following choices hold?
a) (i) is false, but (ii) and (iii) are true
b) (i) and (iii) are false, but (ii) is true
c) (i) and (ii) are false, but (iii) is true
d) (i), (ii) and (iii) are false

25. Which of the following statements are TRUE?

(S1) TCP handles both congestion and flow control
(S2) UDP handles congestion but not flow control
(S3) Fast retransmit deals with congestion but not flow control
(S4) Slow start mechanism deals with both congestion and flow control
a) S1, S2 and S3 only
b) S1 and S3 only
c) S3 and S4 only
d) S1, S3 and S4 only
26. Which of the following layer of OSI Reference model is also called end-to-end layer?
a) Network layer
b) Data layer
c) Session layer
d) Transport layer

27. Generally TCP is reliable and UDP is not reliable. DNS which has to be reliable uses
UDP because
a) UDP is slower
b) DNS servers has to keep connections
c) DNS requests are generally very small and fit well within UDP segments
d) None of these

28.

a) (1)
b) (2)
c) (3)
d) (4)

29. What is the maximum size of data that the application layer can pass on to the TCP
layer below?
a) Any size
b) 216 bytes - size of TCP header
c) 216 bytes
d) 1500
30. An ACK number of 1000 in TCP always means that
a) 999 bytes have been successfully received
b) 1000 bytes have been successfully received
c) 1001 bytes have been successfully received
d) None of the above

31. Suppose you are browsing the World Wide Web using a web browser and trying to
access the web servers. What is the underlying protocol and port number that are being
used?
a) UDP, 80
b) TCP, 80
c) TCP, 25
d) UDP, 25

32. Optical fiber uses reflection to guide light through a channel, in which angle of
incidence is ________ the critical angle.
a) Equal to
b) Less than
c) Greater than
d) Less than or equal to

33. Which algorithm is used to shape the bursty traffic into a fixed rate traffic by
averaging the data rate?
a) Solid Bucket Algorithm
b) Spanning Tree Algorithm
c) Hocken Helm Algorithm
d) Leaky Bucket Algorithm

34. The protocol data unit for the transport layer in the internet stack is
a) segment
b) message
c) datagram
d) frame

35. The TCP sliding window

a) can be used to control the flow of information
b) always occurs when the field value is 0
c) always occurs when the field value is 1
d) occurs horizontally

36. Which of the following control fields in TCP header is used to specify whether the
sender has no more data to transmit?
a) FIN
b) RST
c) SYN
d) PSH

37. The maximum payload of a TCP segment is:

a) 65,535
b) 65,515
c) 65,495
d) 65,475

38. Silly Window Syndrome is related to

a) Error during transmission
b) File transfer protocol
c) Degrade in TCP performance
d) Interface problem

39. SSL is not responsible for

a) Mutual authentication of client & server
b) Secret communication
c) Data Integrity protection
d) Error detection and correction

40. Which of the following is not a field in TCP header?

a) Sequence number
b) Fragment offset
c) Checksum
d) Window size

41. Which of the following statements are true?

(a) Three broad categories of Networks are (i) Circuit Switched Networks (ii) Packet
Switched Networks (iii) Message Switched Networks
(b) Circuit Switched Network resources need not be reserved during the set up phase.
(c) In packet switching there is no resource allocation for packets.
a) (a) and (b) only
b) (b) and (c) only
c) (a) and (c) only
d) (a), (b) and (c)

42. Which among the following are delivered by the transport layer in process-to-
process delivery mechanism?
a) Frames
b) Datagrams
c) Packets
d) All of the above

43. Which among the following are uncontrolled and un-registered form of ephemeral
ports in accordance to IANA?
a) Well known Ports
b) Registered Ports
c) Dynamic Ports
d) All of the above

44. What is the purpose of using source & destination port numbers respectively in the
addressing method of transport layer?
a) For Delivery & Reply operations
b) For Reply & Delivery operations
c) Only for Delivery operations
d) Only for Reply operations

45. Which among the several transport services deals with the addresses, protocol utility
class in addition to performance evaluating features of a connection?
a. Connection Management
b. Quality of Service
c. User Interface
d. Status Reporting
46. Which mechanism/s is/are extremely essential in data link and transport layers in
accordance to operational services offered by the transport protocols?
a) Buffering
b) Flow Control
c) Both a & b
d) None of the above

47. Which among the below specified design issues should not be minimized while
designing the system of a computer network?
a. Bandwidth
b. Content Switching
c. Software Overhead
d. All of the above

50. Which TCP timer signifies its contribution in measuring the time of connection
maintenance in TIME_WAIT state?

a. Keep alive Timer

b. Persist Timer
c. Retransmission Timer
d. 2 Maximum Segment lifetime Timer

51. Which among the following specifies the impossibility of updating RTT estimator
during the arrival acknowledgement of retransmitted data especially at the occurrence
of timeout and retransmission phases in TCP?
a. NAGLE algorithm
b. Karn's algorithm
c. Clark's Solution
d. None of the above

52. Which mechanism in transport layer supplies multiple network connections along
with the distribution of traffic over them in a round-robin basis/ fashion?
a. Upward Multiplexing
b. Downward Multiplexing
c. Buffering & Flow Control
d. Crash Recovery
53. STUB is a technique utilized in the client-server operation especially for
implementation of __________
a. RPC
b. RTP
c. RTCP
d. All of the above

54. Which one of the following is a transport layer protocol?

A Stream Control Transmission Protocol
B Internet Control Message Protocol
C Neighbour Discovery Protocol
D Dynamic Host Configuration Protocol

55. What are the functions of the transport layer?

A Multiplexing/ Demultiplexing
B Connection less Services
C Connection oriented service
D Congestion control

56. TCP and UDP are called ________

A Application protocols
B Session protocols
C Transport protocols
D Network protocols

57. Security based connection is provided by which layer?

A Transport layer
B Application layer
C Network layer
D Session layer

58. TCP is the standard protocol with std no?

A5
B4
C7
D3
59. Buffer overrun can be reduced by using what?
A Traffic control
B Flow control
C Byte orientation
D Data integrity

60. Transport layer is which layer in OSI model?

A Fourth layer
B Third layer
C Second layer
D Fifth layer

61. FCP stands for _________

A Fiber Channel Protocol
B Field Channel Protocol
C Fast Channel Protocol
D Fiber Carrying Protocol

62. A connectionless protocol treats each segment

A Freely
B Independently
C Separately
D Dependently

63. In transport layer, message is divided into transmittable

A Segments
B packets
C frames
D None of the above

64. Transport layer is responsible for process-to-process delivery of the

A Address of Message
B Message
C Few Packets of Message
D Partial Message
65. Class C lies between
A 1240-25511
B 1192-22311
C 0 to 127
D 1128-19111

66. Maximum size of an IPv4 packet would be

A 2048 bytes
B 4064 bytes
C 1024 bytes
D 3098 bytes

67. Frames that are used for initial communication between stations and access points
are called
A Management Frames
B Beacon Frame
C Control frames
D Data frames

68. Web pages are stored at the

A Server
B Client
C Domain
D Mail Server

69. At transport layer, TCP/IP defines

A Stream Control Transmission Protocol
B User Datagram Protocol
C Transmission Control Protocol
D All of the above

70. Transport layer may be responsible for flow and error Control, like the
A Data Link Layer
B Physical Layer
C Subnet Layer
D Application Layer
71. In transport layer, a message is normally divided into transmittable
A Frames
B Signals
C Networks
D Segments

72. Congestion control can control traffic entry into a telecommunications network, so
to avoid _________
A Congestive collapse
B Congestive connection
C Connection collapse
D Collapse congestive

73. Transport layer receives data in the form of __________

A Byte streams
B Bits stream
C Packets
D Both packets and Byte stream

74. Transport layer can identify the symptoms of overload nodes using _________
A Traffic control
B Flow control
C Byte orientation
D Data integrity

75. Using which method in transport layer data integrity can be ensured?
A Checksum
B Repetition codes
C Cyclic redundancy checks
D Error correcting codes

76. Which services are provided by transport layer?

A Error control
B Connection service
C Connection less service
D Congestion control
77. Transport layer protocols deals with
A process to process communication
B application to application communication
C node to node communication
D none of the mentioned

78. A _____ is a TCP name for a transport service access point.

A node
B pipe
C port
D none of the mentioned

79. Which one of the following is a version of UDP with congestion control?
A stream control transmission protocol
B structured stream transport
C datagram congestion control protocol
D none of the mentioned

80. Socket-style API for windows is called

A Winsock
B Wsock
C Wins
D None Of The Mentioned

81. An endpoint of an inter-process communication flow across a computer network is

called
A socket
B pipe
C port
D none of the mentioned

82. Transmission control protocol is

A connection oriented protocol
B uses a three way handshake to establish a connection
C receives data from application as a single stream
D all of the mentioned
83. Transport layer aggregates data from different applications into a single stream
before passing it to
A network layer
B data link layer
C application layer
D physical layer

84. Which one of the following is a transport layer protocol used in networking?
A TCP
B UDP
C Both TCP and UDP
D None of the mentioned

85. User datagram protocol is called connectionless because

A all UDP packets are treated independently by transport layer
B it sends data as a stream of related packets
C it is received in the same order as sent order
D none of the mentioned

86.Which of the following services use TCP?

1. DHCP
2. SMTP
3. HTTP
4. TFTP
5. FTP
A. 1 and 2
B. 2, 3 and 5
C. 1, 2 and 4
D. 1, 3 and 4

87. What layer in the TCP/IP stack is equivalent to the Transport layer of the OSI
model?
A. Application
B. Host-to-Host
C. Internet
D. Network Access
88. Which of the following describe the DHCP Discover message?

1. It uses FF:FF:FF:FF:FF:FF as a layer 2 broadcast.

2. It uses UDP as the Transport layer protocol.
3. It uses TCP as the Transport layer protocol.
4. It does not use a layer 2 destination address.
A. 1 only
B. 1 and 2
C. 3 and 4
D. 4 only

89. You want to implement a mechanism that automates the IP configuration, including
IP address, subnet mask, default gateway, and DNS information. Which protocol will
you use to accomplish this?
A. SMTP
B. SNMP
C. DHCP
D. ARP

90. Which of the following is private IP address?

A. 12.0.0.1
B. 168.172.19.39
C. 172.15.14.36
D. 192.168.24.43

91. Which of the following allows a router to respond to an ARP request that is intended
for a remote host?
A. Gateway DP
B. Reverse ARP (RARP)
C. Proxy ARP
D. Inverse ARP (IARP)

92. TheDoD model (also called the TCP/IP stack) has four layers. Which layer of the
DoD model is equivalent to the Network layer of the OSI model?
A. Application
B. Host-to-Host
C. Internet
D. Network Access

93. Which of the following services use UDP?

1. DHCP
2. SMTP
3. SNMP
4. FTP
5. HTTP
6. TFTP
A. 1, 3 and 6
B. 2 and 4
C. 1, 2 and 4
D. All of the above

94. Which class of IP address provides a maximum of only 254 host addresses per
network ID?
A. Class A
B. Class B
C. Class C
D. Class D

95. If you use either Telnet or FTP, which is the highest layer you are using to transmit
data?
A. Application
B. Presentation
C. Session
D. Transport

97. Which of the following are layers in the TCP/IP model?

1. Application
2. Session
3. Transport
4. Internet
5. Data Link
6. Physical
A. 1 and 2
B. 1, 3 and 4
C. 2, 3 and 5
D. 3, 4 and 5
98. Which layer 4 protocol is used for a Telnet connection?
A. IP
B. TCP
C. TCP/IP
D. UDP

99. Which statements are true regarding ICMP packets?

1. ICMP guarantees datagram delivery.
2. ICMP can provide hosts with information about network problems.
3. ICMP is encapsulated within IP datagrams.
4. ICMP is encapsulated within UDP datagrams.
A. 1 only
B. 2 and 3
C. 1 and 4
D. All of the above

100. Which of the following are TCP/IP protocols used at the Application layer of the
OSI model?
1. IP
2. TCP
3. Telnet
4. FTP
5. TFTP
A. 1 and 3
B. 1, 3 and 5
C. 3, 4 and 5
D. All of the above

101. What protocol is used to find the hardware address of a local device?
A. RARP
B. ARP
C. IP
D. ICMP

102. Which of the following protocols uses both TCP and UDP?
A. FTP
B. SMTP
C. Telnet
D. DNS

103. What is the address range of a Class B network address in binary?

A. 01xxxxxx
B. 0xxxxxxx
C. 10xxxxxx
D. 110xxxxx

104.To use the services of UDP, we need _________ socket addresses.

A. Four
B. two
C. three
D. one

105. Transport layer protocols deals with

A. Application to application communication
B. Process to process communication
C. Node to node communication
D. Routing

106. In stop and wait protocol___________

A. Sequence number are required.
B. Sequence number are not required.
C. Waiting Sequence.
D. Ack required.

107. Multiplexing done at _______ side.

A. Sender
B. Receiver
C. Channel
D. Routing

108.For Stop-and-Wait ARQ, for 10 data packets sent, _______ acknowledgments are
needed.
A. exactly 10
B. less than 10
C. more than 10
D. only one

109. Transport layer aggregates data from different applications into a single stream
before passing it to __________
A. data link layer
B. application layer
C. physical layer
D. network layer

110. Each segment as an independent packet and delivers it to the transport layer at the
destination machine is called_____
A. Connection Oriented
B. Connectionless
C. Segmentation
D. Reassembly

111._______ control refers to a set of procedures used to restrict the amount of data that
the sender can send before waiting for acknowledgment.
A. Flow
B. Error
C. Transmission
D. Data

112. In case of rdt2.2 receiver can send _______ reply to sender.

A. Only ACK
B. Only NAK
C. Both ACK and NAK
D. Nothing

113. Demultiplexing done at _______ side.

A. Sender
B. Receiver
C. Both side
D. Channel
114. The checksum is used for _______.
A.data recovery
B.data transfer
C. error detection
D.error recovery

115.A _______________ protocol provides logical communication between processes

running on different hosts.
A. transport-layer
B. application-layer
C. network-layer
D. session-layer

116. _______ is a flow characteristic that applications can tolerate in different degrees.
A) Reliability
B) Delay
C) Jitter
D) Bandwidth

117. The _______ defines the maximum data rate of the traffic.
A) peak data rate
B) maximum burst size
C) effective bandwidth
D) none of the above

118. In Frame Relay, the _____________ defines an average rate in bits per second.
A) access rate
B) committed burst size
C) committed information rate
D) excess burst size

119. In ________ congestion control, policies are applied to prevent congestion before it
happens.
A) open-loop
B) closed-loop
C) either (a) or (b)
D) neither (a) nor (b)
120. In ________ we try to avoid traffic congestion.
A) congestion control
B) quality of service
C) either (a) or (b)
D) both (a) and (b)

121. _________ is a characteristic that a flow needs. Lack of it means losing a packet or
acknowledgment, which entails retransmission.
A) Reliability
B) Delay
C) Jitter
D) Bandwidth

122. In a network, after the load reaches the capacity, throughput _______.
A) increases sharply
B) increases proportionally with the load
C) declines sharply
D) declines proportionally with the load

123. In _________ queuing, the packets are assigned to different classes and admitted to
different queues. The queues, however, are weighted based on the priority of the
queues; higher priority means a higher weight. The system processes packets in each
queue in a round-robin fashion with the number of packets selected from each queue
based on the corresponding weight.
A) FIFO
B) priority
C) weighted fair
D) none of the above

124. In ATM, the _________ class is a best-effort delivery service that does not
guarantee anything.
A) CBR
B) VBR
C) ABR
D) UBR
125. The________ normally refers to the maximum length of time the traffic is
generated at the peak rate.
A) peak data rate
B) maximum burst size
C) effective bandwidth
D) none of the above

126. In _______ congestion control, mechanisms are used to alleviate congestion after it
happens.
A) open-loop
B) closed-loop
C) either (a) or (b)
D) neither (a) nor (b)

127. _______ happens in any system that involves waiting.

A) Congestion
B) Jamming
C) Error
D) none of the above

128. In the ________ algorithm of TCP, the size of the congestion window increases
exponentially until it reaches a threshold.
A) slow-start
B) congestion avoidance
C) congestion detection
D) none of the above

129. In Frame Relay, the user can never exceed the_________.

A) access rate
B) committed burst size
C) committed information rate
D) excess burst size

130. In the ___________ algorithm of TCP, the size of the threshold is dropped to one-
half, a multiplicative decrease.
A) slow-start
B) congestion avoidance
C) congestion detection
D) none of the above

131. In _________, when a source makes a reservation, it needs to define a flow

specification.
A) Integrated Services
B) Differentiated Services
C) Connectionless
D) Connection-Oriented

132. A _________ traffic model has a data rate that does not change.
A) constant bit rate
B) variable bit rate
C) bursty
D) none of the above

133. ________ is the variation in delay for packets belonging to the same flow.
A) Reliability
B) Delay
C) Jitter
D) Bandwidth

134. A ___________ is a packet sent by a node to the source to inform it of congestion.

A) backpressure
B) choke packet
C) implicit signaling
D) explicit signaling

135. In ATM, the _________ class delivers cells at a minimum rate. If more network
capacity is available, this minimum rate can be exceeded.
A) CBR
B) VBR
C) ABR
D) UBR

136. In the ________ traffic model, the rate of the data flow changes in time, with the
changes smooth instead of sudden and sharp.
A) constant bit rate
B) variable bit rate
C) bursty
D) none of the above

137. In __________, there is no communication between the congested node or nodes

and the source. The source guesses that there is a congestion somewhere in the network
from other symptoms.
A) backpressure
B) choke packet
C) implicit signaling
D) explicit signaling

138. In a network, when the load reaches the network capacity, the delay _______.
A) increases sharply
B) decreases sharply
C) remains constant
D) cannot be predicted

139. The technique of ________refers to a congestion control mechanism in which a

congested node stops receiving data from the immediate upstream node or nodes.
A) backpressure
B) choke packet
C) implicit signaling
D) explicit signaling

140. In ________ queuing, packets are first assigned to a priority class. Each class has
its own queue.
A) FIFO
B) priority
C) weighted fair
D) none of the above

141. In ________, queuing packets wait in a buffer (queue) until the node (router or
switch) is ready to process them.
A) FIFO
B) priority
C) weighted fair
D) none of the above

142. Traditionally, ________types of characteristics are attributed to a flow.

A) two
B) three
C) four
D) five

143. In Frame Relay, the ___________ is the maximum number of bits in excess of Bc
that a user can send during a predefined time.
A) access rate
B) committed burst size
C) committed information rate
D) excess burst size

144. In a network, when the load is below the capacity of the network, the throughput
______________.
A) increases sharply
B) increases proportionally with the load
C) declines sharply
D) declines proportionally with the load

145. In the __________ method, the signal is included in the packets that carry data.
A) backpressure
B) choke packet
C) implicit signaling
D) explicit signaling

146. In a network, when the load is much less than the capacity of the network, the
delay is _________.
A) at a maximum
B) at a minimum
C) constant
D) none of the above
147. Congestion in a network or internetwork occurs because routers and switches have
_______.
A) tables
B) queues
C) crosspoints
D) none of the above

148. In _________, we try to create an appropriate environment for the traffic.

A) congestion control
B) quality of service
C) either (a) or (b)
D) both (a) and (b)

149. In Frame Relay, the ________ bit warns the sender of congestion in the network.
A) BECN
B) FECN
C) either (a) or (b)
D) neither (a) nor (b)

150. In Frame Relay, the ________ bit is used to warn the receiver of congestion in the
network.
A) BECN
B) FECN
C) either (a) or (b)
D) neither (a) nor (b)

151. The ________ is a function of three values: average data rate, peak data rate, and
maximum burst size.
A) peak data rate
B) maximum burst size
C) effective bandwidth
D) none of the above
Solution:

152. In the _________ algorithm of TCP, the size of the congestion window increases
additively until congestion is detected.
A) slow-start
B) congestion avoidance
C) congestion detection
D) none of the above

153. In ATM, the _________ class is divided into two subclasses: real-time (VBR-RT)
and non-real-time (VBR-NRT). VBR-RT is designed for those users who need real-time
services (such as voice and video transmission) and use compression techniques to
create a variable bit rate. VBR-NRT is designed for those users who do not need real-
time services but use compression techniques to create a variable bit rate.
A) CBR
B) VBR
C) ABR
D) UBR

154. Traffic ______ are qualitative values that represent a data flow.
A) controls
B) descriptors
C) values
D) none of the above

155. _________ is a class-based QoS model designed for IP.

A) Integrated Services
B) Differentiated Services
C) Connectionless
D) Connection-Oriented

156. In the ______ bucket algorithm, bursty chunks are stored in the bucket and sent
out at an average rate.
A) leaky
B) token
C) either (a) or (b)
D) neither (a) nor (b)
157. The _______ bucket algorithm allows idle hosts to accumulate credit for the future
in the form of tokens.
A) leaky
B) token
C) either (a) or (b)
D) neither (a) nor (b)

158. In ATM, the _________ class is designed for customers who need real-time audio or
video services. The service is similar to that provided by a dedicated line such as a T
line.
A) CBR
B) VBR
C) ABR
D) UBR

159. In the ______ traffic model, the data rate changes suddenly in a very short time.
A) constant bit rate
B) variable bit rate
C) bursty
D) none of the above

160. In Frame Relay, a ___________ is the maximum number of bits in a predefined

time that the network is committed to transfer without discarding any frame or setting
the DE bit.
A) access rate
B) committed burst size
C) committed information rate
D) excess burst size