Computer Networks - May 2012

Information Technology (Semester 4)

TOTAL MARKS: 80
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any three from the remaining questions.
(3) Assume data if required.
(4) Figures to the right indicate full marks. 1 (a) With a neat diagram compare the uses and functions of different hardware components/devices in an internetwork.(10 marks) 1 (b) Compare virtual circuits and datagram subnets and show their diagrammatic representation during congestion control. (10 marks) 2 (a) What are the advantages of variable length frame over fixed length frames. Explain the different framing methods. (10 marks) 2 (b) Explain FDMA, TDMA and CDMA. (10 marks) 3 (a) Derive the efficiency of pure ALOHA protocol. (10 marks) 3 (b) A receiver receives the code 11001100111. When it applies the hamming code algorithm the result is 0101. Which bit has the error? What is the correct hamming code? (10 marks) 4 (a) Describe the IPv4 header format in detail.(10 marks) 4 (b) Explain the three protocol scenarios for establishing a connection using a 3-way handshake in TCP. (10 marks) 5 (a) Explain DVR routing algorithm and mention the drawbacks of the algorithm when put into practice. (10 marks) 5 (b) Explain the working of Transactional TCP. (10 marks) 6 (a) List the design features to be taken care of as congestion prevention policies in the different layers of network(10 marks) 6 (b) Draw the layered structures and compare the two network reference models OSI and TCP/IP. (10 marks)

Write short notes on (any two):-

7 (a) SONET.(10 marks) 7 (b) Ethernet frame formats.(10 marks) 7 (c) ADSL.(10 marks) 7 (d) Satellite Communication.(10 marks)