Tribhuvan University

Institute of Science and Technology

2076

Bachelor Level / fourth-semester / Science

Computer Science and Information Technology( CSC263 )

Computer Networks

Full Marks: 60 + 20 + 20

Pass Marks: 24 + 8 + 8

Time: 3 Hours

Candidates are required to give their answers in their own words as far as practicable.

The figures in the margin indicate full marks.

Section A

Attempt any Two questions. (2x10=20)

1

Explain each layer of TCP/IP model in detail. Compare it with OSI model.

2

Define transmission media. What are different types of transmission media. Explain different types of unguided media in detail.

3

Define flow control. Explain Go-Back-N ARQ with suitable example. How is it different from Stop-and-Wait ARQ?

Section B

Attempt any Eight questions. (8x5=40)

4

Define network topology. Explain ring topology along with its merits and demerits.

5

Explain LAN with example. How is it different from PAN?

6

Define routing table. Differentiate static routing table with dynamic routing table.

7

What is switching? Compare and contrast a circuit-switched network and packet-switched network.

8

Why do we need wireless LAN? Explain the architecture of IEEE 802.11 in detail.

9

What is NAT? How does it work? What are its benefits?

10

In a block of address, we know the IP Address of one host is 192.34.12.56/28. What are the first address(network address)  and the last address (limited broadcast address) in this block?

11

Why do we need a DNS system when we can directly use an IP address? what is domain name space?

12

Write short notes on (any two):

  1. Connection-oriented service
  2. Bridge
  3. Hamming distance