!i! CSE Rockerz !i!

Department of Computer Science and Engineering
Common to CSE & IT
B.E/B.Tech Degree Cycle Test – II, September 2011

Branch: CSE Year/Semester: III / V
Subject Name: Computer Networks Max Marks: 50

Part – A (09 x 02 = 18)

1. Justify why packet switching is more suitable to data transmission
2. List the two forms in which virtual circuit packet switching is implemented
3. Is 3.54.81.76 a class A, B, C, or D IP address? What are the network ID and host
ID in decimal notation? Assume that the subnets are not used.
4. What field in the IP datagram header is used to avoid forwarding datagram's endlessly
through routing loops? How is the header used to accomplish that?
5. What is the need of ARP ?
6. Give some examples of error messages provided by ICMP?
7. What are the three methods that support IP address allocation in DHCP?
8. Name the two queuing algorithms used in routers. Differentiate their working principle
9. State which layers of the ISO OSI model does the following
Interconnecting devices operate.
(1) Repeaters (2) Bridges (3) Routers (4) Gateways

Part-B (02 x 16 =32)

10 (a) i. Explain in detail about the different queuing disciplines (8)
ii. Briefly explain about ARP, DHCP (8)
(Or)
(b) i. Give the format of IPv4 packet and explain the function of each field (8)
ii. Explain Spanning tree algorithm with an example (8)

11. (a) i. Differentiate DVR and LSR techniques. (8)
ii. An organization is granted a site address 130.56.0.0 & Company needs 1024
Subnets. (8)
a) Find subnet mark.
b) Find the no. of address in each subnet
c) Find 1st and last address in subnet 1
d) Find 1st and last subnet 1024
(Or)
(b) i. Given the network topology below, use a link-state algorithm to
Compute the shortest path from A to all other nodes. Make sure to show the results
of the computation at each step. (12)

ii. Describe collision avoidance mechanism used in 802.11 wireless LAN. In particular
how such a mechanism solves the hidden terminal problem (4)


Prepared by Approved by

Dr K.Komathy
Dr S.Chitrakala(HOD /CSE)