CS206 Assignment 2 Solution and Discussion Spring 2020

[moaaz]

Re: CS206 Assignment 1 Solution and Discussion

Assignment No. 01
Semester: Fall 2020
CS206: Introduction to Network Design & Analysis Total Marks: 15
Due Date: 29th May, 2020

Instructions:
Please read the following instructions carefully before submitting assignment:
You need to use MS word document to prepare and submit the assignment on VU-LMS.
It should be clear that your assignment will not get any credit if:

 The assignment is submitted after due date.
 The assignment is not in the required format (.doc or docx)
 The submitted assignment does not open or file is corrupt.
 Assignment is copied (partial or full) from any source (websites, forums, students, etc)

Objectives:

To enhance the learning capabilities of the students about:

• Ethernet LAN
• MAC addressing
• Learning process of switch

Assignment

Scenario:
The following diagram is a representation of an Ethernet based network comprising of eight Personal computers and a server connected with each other through a switch:

[center][/center]

After carefully analyzing above diagram, you are required to do the following tasks:

Task 1:
Let’s assume that the network has just been powered on and there hasn’t been any flow of traffic occurred over the network yet.
a) What might be in the MAC address table of the switch?
b) If PC-1 sends a packet to PC-4, what action(s) will be performed by the switch?

Solution:

Task 2:

Now assume that some data transfer has been occurred between the following devices:
i. PC-1 and PC-4
ii. PC-7 and PC-5
iii. PC-3 and Server
iv. PC-5 and PC-8

What might be in the forwarding table of the switch? Give your answer in the following format:

MAC Address	Port Number

| |

Solution:

Task 3:
Let’s assume that PC-1, PC-2, PC-3 and PC-4 belong to accounts department and PC-5, PC-6, PC-7 and PC-8 belong to admin department of an organization. Both departments have some concerns regarding security of their relevant departmental data, and they want to restrict unnecessary transfer of irrelevant traffic from each other. What approach can be implemented at the switch level to separate out network traffic of both the departments without changing the physical network configuration?

Solution:

Best of Luck!

[moaaz]

Please solution idea

[moaaz]

@moaaz said in CS206 Assignment 1 Solution and Discussion:

ask 1:
Let’s assume that the network has just been powered on and there hasn’t been any flow of traffic occurred over the network yet.
a) What might be in the MAC address table of the switch?
b) If PC-1 sends a packet to PC-4, what action(s) will be performed by the switch?
Solution:
Solution:

a) As the network is just switched on, so is the switch. Therefore, there will be no entry in the Address table (forwarding table) of the switch.
b) Switch will perform two operations. First it will check its MAC address table which is empty, and it will populate its address table with the MAC entry of the incoming packet. Secondly, it will repeat the incoming packet on all its ports other than the source port.

Task 2:

Now assume that some data transfer has been occurred between the following devices:
i. PC-1 and PC-4
ii. PC-7 and PC-5
iii. PC-3 and Server
iv. PC-5 and PC-8

What might be in the forwarding table of the switch? Give your answer in the >following format:

Solution:

MAC Address	Port Number
0200.1111.1111	Fa0/1
0200.1111.4444	Fa0/4
0200.1111.7777	Fa0/7
0200.1111.5555	Fa0/5
0200.1111.3333	Fa0/3
0100.1111.1111	Fa0/9
0200.1111.8888	Fa0/8

Task 3:
Let’s assume that PC-1, PC-2, PC-3 and PC-4 belong to accounts department and PC-5, PC-6, PC-7 and PC-8 belong to admin department of an organization. Both departments have some concerns regarding security of their relevant departmental data, and they want to restrict unnecessary transfer of irrelevant traffic from each other. What approach can be implemented at the switch level to separate out network traffic of both the departments without changing the physical network configuration?

Solution:
Both networks can be separated out by creating two VLANs on the switch and registering appropriate interfaces on the VLANs. This network behaves just like it would with the two physical switches. Switch does learn all the MAC addresses, but the switch does not forward broadcasts or unicasts from one VLAN to the other. It keeps a separate address table for each VLAN. This way both departments will be separated out.