Guru Gobind Singh Indraprastha Vishwavidyalaya 2006-6th Sem B.Tech [] - , Code : ETEC – 308 Subject : Data Communication Networks - Question Paper

First-Term exam
6th Semester [B.Tech] - February 2006

Paper Code : ETEC – 308 Subject : Data Communication Networks

Time : 11/2 Hours
Maximum Marks : 30

Note : Attempt any three ques. in all. Q1 is compulsory. every ques. carries 10 marks.


Q1
( a )
How flow control is various than fault control?


( b )
List the disadvantages of using piggybacking.
( c ) List the factors that will determine the length of the sliding window.
( d ) Name any 3 protocols of the data link layer.
( e ) obtain the binary equivalent of x4 + x3 + x one
( f )
How bit rate and baud rate are correlated.
( g ) compute the maximum possible bit rate for a noiseless channel with a bandwidth of 3500Hz, transmitting a signal with eight signal levels.
( h ) What is the advantage of using Trellis coded modulation?
( i ) How DSL modem can support high speed digital communication over traditional telephone loops.
( j ) explain the advantages of using packet switching over circuit switching.


Q2
( a )
List the differences ranging from the OSI and TCP/IP model.


( b )
elaborate the advantages of PSK over ASK. Draw the constellation diagram if the data points are (2,0), (2,2), (-2,0) and (-2,-2). Is the modulation ASK, PSK or QAM.



Q3
( a )
elaborate the various kinds of redundancy checks used in data communication?

( b )
describe CSMA/CD protocol and its advantages over CSMA protocol.


Q4
( a )
explain sliding window protocol? explain the criteria for choosing the sender and receiver sliding window size with suitable example.

( b )
Name the kinds of HDLC frames. In HDLC, what is bit stuffing and why is it needed?

Earning:   Approval pending.