# CS601 Assignment 1 Solution Fall 2017

Instructions:

• You will submit your assignment before or on due date on VU-LMS.
• Assignment sent via Email will not be replied and accepted/graded in any case.
• If the submitted assignment does not open or file is corrupt, it will not be graded.
• Assignment should be completed by your own efforts it should not be copied from internet, handouts or books.
• You will submit solution only in the Microsoft Word File.
• Assignment is covered from lectures 1 to 8.

Assignment Questions

Questions:                                                                                                           Marks 15

Question. 1 Assume 50 students are  performing following different activities on different computers according to their need in a VU LAB. All the computers contains 4GB RAM, Intel Core i5 processor, 2.7 GHz clock speed and 500 GB SATA, connected to one LAN through fiber optic cable providing  internet speed of 5 Gbps. In this VU LAB which of the following applications are more sensitive to delay?(1.25 * 4) = 5(5 Marks)

1.      Sending an e-mail

2.      Copying a file

3.      Surfing the Internet

1.      Sending an e-mail

Not sensitive to delay because it is not an interactive application.

2.      Copying a file

Not sensitive to delay because we do not expect a file to be copied immediately.

3.      Surfing the Internet

It is very sensitive to delay because we expect to get access to site we are browsing very quickly.

As it is also an interactive application, it is also very sensitive to delay.

Question. 2 Assume there are 100 devices in a network, how many number of cable links are needed for mesh and star topology?Give Formulae and Calculation Both.(3+2= 5 Marks)

Mesh
Formula: n(n-1)/2 (where n = number of devices)
= 100(100-1)/2
= 100(99)/2
= 9900/2
= 4950

Star
Formula: n = number of devices
n = 100

Question. 3   Match the following to their relevant layer of the OSI model:                       (5 Marks)

1. Detection of error between nodes
2. Selection of route
3. Transmission of bit stream across physical medium.
4. Ensures reliable transmission of data
5. Defines frames

a.     Detection of error between nodes

b.      Selection of route
OSI Layer: Network

c.       Transmission of bit stream across physical medium.
OSI Layer: Physical

d.      Ensures reliable transmission of data
OSI Layer: Transport

e.       Defines frames