CS-601 Assignment No 1 Solution:-

Assignment No. 01

Semester: Fall 2017
Data Communication– CS601

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.      Sending an e-mail

2.      Copying a file

3.      Surfing the Internet

4.      Login to VULMS

Answer:-
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. 


4.      Login to VULMS

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.

Answer:

Number of cable links in mesh topology= n (n-1)/2

=100(100-1)/2

=4950

Number of cable links in star topology will be 100 because in star topology every device needs only 1 node.

Question.3   Match the following to their relevant layer of the OSI model:                       

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

Answer:

6.      Detection of error between nodes	Transport Layer
7.      Selection of route	Network Layer
Transmission of bit stream across physical medium.	Physical Layer
Ensures reliable transmission of data	Transport Layer
8.      Defines frames	Data Link Layer

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