Computer Networks Answers

In the IPv4 Header format following information is given in decimal number system, with

respect to the given information calculate the header checksum value. (10)

VER=4

HLEN =6

Service type=9

Total length=26

Identification=2

Flag=3

Fragmentation offset=0

Time to live=5

Protocol=12

Source IP Address=11.13.12.6

Destination IP Address=10.6.8.11

Find the first address, last address and the number of addresses of a network whose one

of the IP addresses is 50.28.22.75 / 25.

(5 marks question).

Mention and explain each field of IPv4 header in detail, by taking suitable examples.

(5 marks)

Q1.2: Explain the different methods for random media access control? (5 marks)

Differentiate among flow control mechanisms by taking suitable examples.

According to Recent Media, Amazon Web Services recently had to defend against a DDoS assault with a peak traffic level of 2.3 Tbps, the most ever recorded. According to Amazon's Q1 2020 threat report, the incident happened in February and was neutralized by AWS Shield, a solution meant to protect users of Amazon's on-demand cloud computing platform against DDoS attacks, malicious bots, and application vulnerabilities. The corporation did not reveal the attack's aim or its source.

Your task is to compile a complete report on the attack mentioned above, considering the following criteria.

-Attack Mechanism.

-Impact of the Attack.

-Mitigation Techniques applied by the organization.

-As a cyber security officer, what will be your strategy to encounter such scale of the attack.

Describe how domain name service (DNS) works and how DNS add efficiency to a network. Explain and illustrate the operation using a diagram.

What is end-to-end congestion control and how is it achieved in TCP?

Describe the functionality provided by the transmission control protocol (TCP)

A 4-stage pipeline has the stage delays as 150, 120, 160 and 140

nanoseconds respectively. Registers that are used between the stages have a

delay of 5 nanoseconds each.

Question: Assuming constant clock rate, calculate the total time taken to

process 1000 data items on this pipeline.