Search This Blog

Friday, 26 June 2015

Data Communication and Networks-Model question paper for B.E/B.Tech Engineering



1(a) Explain the concept of networks and types of computer networks. (6 Marks)
(b) What is TCP/IP protocol architecture? Explain. (6 Marks)
(c) Draw the block diagram of a general communication model and explain the function of each block. (8 Marks)
2 (a) Discuss salient features of OSI reference model. (6 Marks)
(b) What is the difference between virtual and actual communication? (6 Marks)
(c) Why do we use layered protocols? Give reasons. (8 Marks)
3(a) With the help of suitable waveforms explain the Manchester and quaternary NRZ formats. What are the advantages of using the Manchester format over the other formats? (8 Marks)
(b) What is the effect of twisting the wires in UTP cables? (4 Marks)
(c) State and explain various properties of line codes. (4 Marks)
(d) What is the difference between source coding and line coding? (4 Marks)
4(a) A bit stream 10011101 is transmitted using the standard CRC method. The generator polynomial is x3+1. Show the actual bit string transmitted. Suppose the third bit from left is inverted during transmission. Show that this error is detected at the receiver end. (6 Marks)
(b) Explain about the role of minimum distance in error correction and detection. (4 Marks)
(c) What is piggybacking? (4 Marks)
(d) Given an error free 64 kbps satellite channel which is used to send 512 byte data frames in one direction with very short acknowledgements coming back the other way. What will be the maximum throughput for window sizes of 1, 7, 15 and 127. (6 Marks)
5(a) What is the maximum and minimum length of frame of traditional Ethernet? Explain briefly. (6 Marks)
(b) How can you compare 1-persistent CSMA and P-persistent CSMA? What part of the 802 project makes use of CSMA/CD? (6 Marks)
(c) Why can not Ethernet and token ring be used in WAN? Explain. (4 Marks)
(d) Fast Ethernet has the same 64-byte minimum frame size but can get bits out ten times faster. How is it possible to maintain the same minimum frame size? How much bandwidth loss will occur in this case? (4 Marks)
6(a) Explain different carrier sense protocols. How are they different than collision-free protocols? (5 Marks)
(b) Describe the access method used by Ethernet (IEEE) network, and the cable and connectors used by Ethernet network. (6 Marks)
(c) Discuss briefly the advantages and disadvantages of FDDI and Ethernet LAN technologies. (4 Marks)
(d) Evaluate ring latency of 20 stations separated by 100 meters and operate at a speed of 4 Mbps. Assume the delay introduced by each station to be 2.5 bit. (5 Marks)
7(a) With the help of suitable explanatory diagrams, explain about the routers and gateways. (8 Marks)
(b) A class B network on internet has a subnet mask of 255.255.240.0. What will be the maximum number of hosts per subnet? (4 Marks)
(c) What is firewall? What is the difference between packet filtering and proxy server gateways? (4 Marks)
(d) A computer on a 6 Mbps network is regulated by token bucket. Token bucket filled at a rate of 1 Mbps. It is initially filled to a capacity of 8 megabytes. How long can computer transmit at the full 6 Mbps? (4 Marks)
8(a) What is meant by fragmentation? Is fragmentation needed in concentrated virtual circuit internets, or any in datagram system? (5 Marks)
(b) Differentiate between the static and dynamic routing with their pros and cons. Give example of some routing protocols used in both type of routing. (6 Marks)
(c) Give an efficient algorithm for finding the shortest parts between all pairs of nods in a tree. What is the complexity of the algorithm? (4 Marks)
(d) An ATM network uses a token bucket scheme for traffic shaping. A new token is put into bucket every 5 Microseconds. What is the maximum sustainable net data rate. Exclude the header bits. (5 Marks)

No comments:

Post a Comment