Computer Communication Networks - Dec 2013

Electronics & Communication (Semester 7)

TOTAL MARKS: 100
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any four from the remaining questions.
(3) Assume data wherever required.
(4) Figures to the right indicate full marks. 1 (a) With layer diagram, explain the responsibility of each layer in OSI model.(10 marks) 1 (b) How data transfer is achieved using Cm and CMIS in CATV channel?(6 marks) 1 (c) Calculate the minimum time required to donwload one million bits of information using each of the following techniques:
(i) V.32 modem
(ii) V.32 bis modem
(iii) V.90 modem(4 marks) 2 (a) What are the different types of framming? Explain bit stuffing with an example.(6 marks) 2 (b) With design and sliding window diagrams. Explain Go back - N ARQ prtocol.(10 marks) 2 (c) In a stop and wait ARQ system, the bandwidth-delay product is 20000 bits and 1 bit takes 20 ms to make a round trip. What is the B.W. of the line? If the protocol that can be send frames are 1200 bits in length then what is the percentage of utilization of the link?(4 marks) 3 (a) One hundred stations on a slotted ALOHA network share 1 mbps channel. If frames are 1000 bits long. Find the throughout if each station is sending 5 frames/second.(5 marks) 3 (b) With flow diagram, explain the procedure for CSMA/CD protocol.(6 marks) 3 (c) Explain polling method of controlled access of the channel.(4 marks) 3 (d) Describe the encoding and decoding scheme in CDMA techniques for channel sharing.(5 marks) 4 (a) Explain the frame formats of IEEE 802.3. What are the minimum and maximum frame lengths?(10 marks) 4 (b) What are the characteristics of fast Ethernet?(4 marks) 4 (c) Describe the address mechanism of IEEE 802.11.(6 marks) 5 (a) What is transparent bridge? Explain the process of learning in transparent bridge.(10 marks) 5 (b) What is VLAN? Explain the detail. What are the advantages of VLAN?(10 marks) 6 (a) What is classful addressing in IPV4? What is its mask? Explain.(6 marks) 6 (b) Find the class of each address:
(i) 14.23.120.8
(ii) 252.5.15.111
(iii) 11000001 10000011 00011011 11111111
(iv) 00000001 00001011 00001011 11101111(4 marks) 6 (c) What is network address translation (NAT)? Give the NAT implementation.(10 marks) 7 (a) Explain different forwarding techniques used in network layer.(10 marks) 7 (b) Explain the distance vector routing for the graph shown in Fig.Q7(b)