Chapter 3 Transport Layer

1. A transport-layer protocol provides for logical communication between ____.

A Application processes B Hosts C Routers D End systems

2. Transport-layer protocols run in ____. A Servers B Clients C Routers D End systems

3. In transport layer, the send side breaks application messages into ____, passes to network layer. A Frames B Segments C Data-grams D bit streams

4. Services provided by transport layer include ____. A HTTP and FTP B TCP and IP C TCP and UDP D SMTP

5. Which of the following services is not provided by TCP A Delay guarantees and bandwidth guarantees B Reliable data transfers and flow controls

C Congestion controls D In-order data transfers

6. These two minimal transport-layer services----____ and ____----are the only two services that UDP provides!

A process-to-process data delivery, error checking B congestion control, reliable data transfer C flow control, congestion control D In-order data transfer, error checking 7. Port number’s scope is ____ to ____. A 0, 1023 B 0, 65535 C 0, 127 D 0,255

8. The port numbers ranging from ____to ____ are called well-known port number and are restricted. A 0, 1023 B 0, 65535 C 0, 127 D 0,255

9. UDP socket identified by two components, they are ____. A source IP addresses and source port numbers B source IP addresses and destination IP addresses C destination IP address and destination port numbers D destination port numbers and source port numbers 10. TCP socket identified by a (an) ____. A 1-tuple B 2-tuple

C 3-tuple D 4-tuple

11. Which of the following applications normally uses UDP services A SMTP

B Streaming multimedia C FTP D HTTP

12. Reliable data transfer protocol over a perfectly reliable channel is____.

A B C D

13. Reliable data transfer protocol over a channel with bit errors and packet losses is ____. A B C D

14. Which of the following about reliable data transfer over a channel with bit errors is not correct

A : assuming ACK and NAK will not be corrupted B : assuming ACK and NAK can be corrupted C : only use ACK-s

D : use both ACK-s and NAK-s

15. Which of the following protocols is not pipelining protocols

A TCP B

C GO-BACK-N D selective repeat

16. Which of the following is not correct about GBN protocol

A Only using ACK-s B Using cumulative ACK-s

C Receiver discards all out-of-order packets D It is not pipelined protocol

17. Which of the following is not correct about SR protocol

A receiver individually acknowledges all correctly received packets

B sender only resends packets for which ACK not received C It limits sequence number of sent but un-ACK-ed packets

D It is not a pipelined protocol

18. Which of the following about TCP connection is not correct A It is a broadcast connection B It is a point-to-point connection C It is a pipelined connection D It is a full duplex connection 19. The SYN segment is used for____. A TCP connection setup B TCP flow control C TCP congestion control D Closing a TCP connection

20. The FIN segment is used for____. A TCP connection setup B TCP flow control C TCP congestion control D Closing a TCP connection

21.How does TCP sender perceive congestion A Through a timeout event