Deakin University SIT202 Computer Networks Problem Solving Report

This assignment solution addresses a problem-solving report on computer networks, focusing on the cookie mechanism. The solution explains the six steps of cookie usage in online shopping, detailing the interactions between the client (web browser) and server, including the role of HTTP and TCP connections. It covers session cookies, session tokens, and how cookies are used to maintain stateful relationships, track user behavior, and facilitate e-commerce transactions. The explanation includes the exchange of cookies between the client and server, the use of cookie headers, and how cookies store and transmit information to enhance the user experience. The assignment references relevant sources to support its explanation of the cookie mechanism and its applications.

Running head: COMPUTER NETWORK
COMPUTER NETWORK
Name of the Student
Name of the University
Author Note

Answer to question 1.a
Simply, cookies are used in order to exchange information among the client and server.
Server also recognize the client request by cookies. Generally, web server and client interact with
each other as client-server system [1]. Data is stored into the server and client can access those
data on request. Cookies are capable of storing only 4KB of data and limit of cookies per domain
is 20. Typically, web browsers functions as a client in order to request desired data from servers.
Web browser as client and server communicate with each other by HTTP. HTTP stands for
hypertext transfer protocol which is a standard application, supports web browsers responses and
requests [2]. HTTP is stateless as all requests roots to a server are totally same and sever are not
able to determine if a request coming from client is already existed or new one. The below figure
describes the mechanism for using the cookie in online shopping [3]. The below figure showcase
the cookie exchange between the client and server. The mechanism is also described below.

Figure 1: cookie using in online shopping [4]
Step 1 & 2: First, client request to get information from Boytoys.com by specifying the URL in
a browser. The web browser established a TCP connection to the server pool or web server
through IP address. Then, browser acknowledged the TCP connection and transfer HTTP request
to the server in order to retrieve the content. This is used to store the cookie for future as when
the same site will be requested the web browser will use the previous connection utilities. In the
second stage, Server conformed the request made by web browser along with set-cookies id

12343. Server responses to the web browser by return the search result. In this case, the server
responds returning the home page along with pages representing toys. Server responses also
comprises all relevant contents of the toys. One of the cookies send by server is known as session
cookie. In this step, the session cookie is produced. The session cookie is formed and it is deleted
when the client shuts down the program or backs from the page, as there is no particular expiry
time for the session cookie [5]. Other cookie is known as session token which contains attributes
to instruct the browser to remove the cookie after a certain amount of time [6].
Step 3 & 4: In the third stage, browser made another request to get any certain image of a toy on
the website. This request also contains a cookie along with a HTTP header. Web browser used
the same set-cookie 12343. Client used the same id in order to acknowledge the server that the
new request is associated with previous request. After acknowledgement, sever transfer cookie to
the web browser. This cookies consist of cookie header. System initiated the response while
modifying the existing cookie or add new ones. In this case, user send requests to the server to
get certain image associated with boy toys which client want to buy from the website. The server
respond with the desired page consist of the required image along with the price. At this stage,
client has the capability to modify the cookie by while modifying the existing cookie or add new
ones. Then, the browser add new cookie value by replacing the old value.
Step 5 & 6: At stage five, client again request for further payment details in order to confirm the
booking. This request also contains a cookie along with a HTTP header. Web browser used the
same set-cookie 12343. Client used the same id in order to acknowledge the server that the new
request is associated with previous request. After acknowledgement, sever sends cookie to the
web browser. This cookies consist of cookie header. System initiated the response while
modifying the existing cookie or add new ones. In this case, client send the request for getting

the payment details associated with certain toy. Then, the server respond with the desired
payment details and confirming the payment which are necessary to proceeds with the payment
required to be made with the item. Further, browser add new values by replacing the old value or
modifying the old value.
Answer to Question 1.b
Answer to Question 2

Reference:
[1]N. Zakas, "HTTP cookies explained - Human Who Codes", Humanwhocodes.com, 2018.
[Online]. Available: https://humanwhocodes.com/blog/2009/05/05/http-cookies-explained/.
[Accessed: 23- Sep- 2018].
[2]A. Ball, "The Cookie is Still Crumbling: The Challenges Facing Cookie Tracking
Research", International Journal of Market Research, vol. 55, no. 1, pp. 34-41, 2013.
[3]"RSA Algorithm key generation Extension", International Journal of Modern Trends in
Engineering & Research, vol. 5, no. 1, pp. 73-75, 2018.
[4]B. Dimitrova and A. Mileva, "Steganography of Hypertext Transfer Protocol Version 2
(HTTP/2)", Journal of Computer and Communications, vol. 05, no. 05, pp. 98-111, 2017.
[5]V. Kazymyr, A. Mokrohuz and M. Moshel, "MINIMAL HTTP HEADER FOR TRAFFIC
CRITICAL APPLICATIONS", TECHNICAL SCIENCES AND TECHNOLOG IES, no. 28, pp.
123-128, 2017.
[6]M. Bassiouni, "Protecting Cookie-Based Internet User Sessions", Journal of
Telecommunications System & Management, vol. 01, no. 03, 2013.