MODEL PAPER

B. Tech (IT) Degree Examination

Third Year - Second Semester

COMPUTER NETWORKS

Effective from the admitted batch of 2004-2005

Time: 3 hrs
Max Marks: 70

First Question is Compulsory

Answer any four from the remaining questions

All Questions carry equal marks

Answer all parts of any question at one place

1.a) Distinguish between backend LANs and backbone LANs
b) What are the possible types of delay in a packet switched network?
c) What is flooding?
d) List the main requirements of a internetworking facility
e) Write the major difference between IP and UDP
f) What is Switching Hub?
g) Write the important functions of Gateway

2. a) Describe the services and types of operation provided by the LLC protocol. Write the basic functions performed by the MAC layer
b) Write in detail the key requirements for a Wireless LAN. Briefly define IEEE 802.11 services

3. a) Compare and contrast circuit switching and packet switching
b) What are the requirements for a routing function for a packet switching network? Develop the static routing table for node A and node D of the following sub-network using one of the routing algorithms and draw the routing diagrams for node A & node D.
------DIAGRAM------

4. a) Explain adaptive routing with its merits and demerits
b) Describe the sequence of events for i) a call from mobile unit to a fixed subscriber ii) a call from fixed subscriber to a mobile unit

5. a) Describe the operation of a Connectionless Internetworking scheme
b) Explain briefly the meaning of the following IP addresses. State also which of the addresses can be used only as source addresses and which ones only as destination addresses
0.0.0.0, 0.0.0.3, 255.255.255.255, 130.29.255.255, 192.117.25.7, 127.0.0.1

6. a) What is TCP? Spell out the acronym and describe TCP briefly. Also tell for what purpose TCP was developed. What pieces of identification information are needed to unambiguously specify a TCP connection? What is the silly window syndrome and how can this problem be solved (at the sending and at the receiving end)
b) Describe the credit scheme used by TCP for flow control.

7. a) Briefly explain radix 64 encoding
b) Explain what e-mail systems can do and how they are organized

8. Write short notes on any Two of the following
a) Token Ring Repeater b) Datagram Operation
c) ICMP d) HTTP