Adikavi Nannaya University (ANU) 2007 B.E Computer Science CS339 - COMPUTER NETWORKS - Question Paper

CS339 - COMPUTER NETWORKS

VI SEMESTER

B.E. COMPUTER SCIENCE AND ENGINEERING

Time: 3 Hours Maximum: 100 Marks

ans All The ques.

PART – A (10 x two = 20 Marks)

1. Why network software is organized as a series of layer?

2. elaborate the 2 types of light sources used in fiber cables?

3. Reliability of CRC is better than that of simple parity and LRC. Justify this statement.

4. What is meant by bit stuffing?

5. Write short notes on virtual circuit organization of the subnet.

6. Differentiate ranging from adaptive and non-adaptive routing algorithms.

7. What is meant by upward and downward multiplexing.

8. Mention a few applications where UDP is preferred over TCP?

9. Mention the layer in which email gateway function. Also mention a few of its applications

10. describe encryption

PART – B (5 x 16 = 80 Marks)

11.i) Compare OSI and TCP / IP reference models on form of their merits and demerits. (10)

ii) Differentiate ranging from broadcast networks and point to point networks. (6)

12.a)i) discuss the CSMA/CD protocol with binary exponential back off algorithm used internet. (10)

ii) presume that a network can cover a distance of 5000 meters and the RTT is 100 µ sec of the network operates at a speed of 20Mbps. What should be the minimum frame size to employ CSMA / CD? (6)

(OR)

12.b)i) discuss the sliding window protocol and compare its performance against the simple stop and wait protocol. (10)

ii) provided message is M(X) = X5 + X4+ X + one and the generator is G(X) = X4+X3+1 calculate CRC. (6)

13.a)i) discuss the distance vector routing algorithm. (8 )

ii) obtain the shortest path from node A to node D in the subsequent network using the Bell mark kord routing algorithm. (Cool

(OR)

13.b)i) provided 3 IP addresses are 32.46.7.3, 200.132.110.35 and 140.75.8.92. obtain their classes, network addresses, broadcast address and their subnet marks. (6)

ii) discuss the token breket algorithm and compare its performance against the leaky bueket algorithm (10)

14.a)i) discuss the Bres-way handshak protocol used to establish the connection in the transport layer. Also discuss the protocol used to release the connection. (6)

ii) discuss the transport service access point and the different schemers used by the transport layer to obtain the TSAP at a server. (8 )

(OR)

14.b)i) discuss the different fields of TCP header. (8 )

ii) Write short notes about the pseudo header included in the TCP checkroom. (4)

iii) Draw the UDP header and discuss its fields (4)

15.a) discuss the DNS in terms of name space, resource record and name server. (16)

(OR)

15.b) discuss the architecture of WWW as on client / server application (16)

Earning:   Approval pending.