Jawaharlal Nehru Technological University Anantapur 2011-3rd Year B.Tech Electronics and Communications Engineering Computer Networks s, - Question Paper

Jawaharlal Nehru Technological University, Anantapur

ans any 5 ques.
All ques. carry equal marks Max Marks:80

1. (a) provide a detailed description of the Novell Netware reference model?
(b) With suitable examples discuss simplex, half-duplex & full-duplex communication.? [10+6]

2. (a) explain different channels supported by ISDN bit pipe?
(b) Differentiate ranging from virtual circuits and circuit switching? [8+8]

3. (a) To give more reliability than a single parity bit can give, an error-detecting coding scheme uses 1 parity bit for checking all the odd numbered bits and a 2nd parity bit for all the even numbered bits. What is the Hamming distance of this code?
(b) explain the functioning of SLIP? [8+8]

4. (a) What is the prime difference ranging from a token bus and a token ring?
(b) A large population of ALOHA users manages to generate 50 requests/sec, including both originals and retransmissions. Time is slotted in the units of 40 msec?
i. What is the chance of success on the 1st attempt?
ii. What is the probability of exactly k collisions and then a success?
iii. What is the expected number of transmission attempts needed? [4+12]

5. What is the effect of link failures in Virtual circuit subnet. Congestion can be easily controlled in Virtual circuit subnet. discuss. Why use of Virtual circuits, increases initial delay ? [16]

6. (a) What is Fair queuing in the situation of congestion control? What is the main issue with fair queuing? How it is solved?
(b) discuss hop-by-hop choke packets method for congestion control? [8+8]

7. (a) What is multiplexing? Why multiplexing is required? What is the difference ranging from upward multiplexing and downward multiplexing?
(b) How to recover from host crashes and router crashes? [8+8]

8. (a) When external viewers are needed? How does a browser know which 1 to use?
(b) What is the difference in transferring compressed and uncompressed video? [8+8]

Earning:   Approval pending.