Extra Credit Homework - 203

Protocol Analysis - Treasure Hunt

This homework is a practical homework on protocol analysis. And you are actually looking for something in the trace this time.

1.0 General Setup

1. Install a network protocol analyzer called Wireshark (http://www.wireshark.org/download.html). You can also use Fiddler ( http://www.fiddler2.com/fiddler2/ ) at the same time.
2. Go to www.yahoo.com to get a new yahoo id for email. Alternatively, you can use an existing id. It will work as long as it is a web based email.

2.0

Trace Capture Part I

1	Make sure you signout of any Yahoo account in the browser that you are using. In order words, create a new Yahoo account in this exercise. Start the network protocol analyzer	Make sure everything works and you can capture HTTP traffic.
2	Click this link	Only use this link
3	Click the "Create your free account" button	Capture the network trace.
4	Complete register and create a flickr account	Pay close attention to the page with username and password field.
5	Upload a photo	Make sure the network protocol analyzer is working. Make sure you have the trace. Stop the analyzer and perform analysis

Trace Capture Part II

1	Make sure you signout of any Yahoo account in the browser that you are using. Start the network protocol analyzer	Make sure everything works and you can capture HTTP traffic. Alternatively, you can use a different browser to have a clean start.
2	Click this link	Only use this link
3	Click the "Try it for 60 Days free" button	Capture the network trace.
4	Complete the registration	Pay close attention to the username and password field.
5	Log back on to the system and checkout the site.	Make sure the network protocol analyzer is working. Make sure you have the trace. Stop the analyzer and perform analysis

3.0 Analysis

You just did a quick audit on two different systems built by a big Internet company and a small company. Flickr is actually a Yahoo company.

For Flickr, some of the pages contain a randomly generated hidden value in the page. Go through your trace and identify those random hidden values. Random in this context is the fact that the value is not the same for different pages generated by the server. You must refer to the trace to get credit. After you identify the hiddle value in the flickr pages. Discuss the following:

• What format is the randomly generated hidden value?
• Refer to the trace and identify the hiddle value.
• Why is a randomly hidden value generated for these flickr pages?

Now, go through the constant contact trace that you captured. Are there any randomly generated hidden value in a page? If yes, please refer to the trace. If not, why not?

Hints:

• You can try using different browser and email login id to see if it makes a different and add to your discussion.
• Email the answer by Dec 9, 2011 11:59pm. However, the earlier the better.