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CSCI322/MCS9322 Session 3, 2011 – Assignment Three Page 1 University of Wollongong School of Computer Science and Software Engineering CSCI322/MCS9322 System Administration Session 3 2011 Assignment 3 (10 marks) Due on the date specified on the SIM CSCI322 assessment schedule. Aim: In this assignment you will be parsing log files from a web proxy. This is an example of a simple task a system administrator may have to embark upon. It is designed to get you warmed up for what comes next in this subject. Task Imagine you work for an Internet Service Provider like exetel or Internode with a number of customers. Each customer has a unique IP address which acts as their identified. In this world the provider only allows users to surf the web using the Hyper Text Transport Protocol (HTTP). When a user logs on to the ISP to get access to the Internet, they would typically use a browser such as Safari (preferably) or IE to view web pages. When the user wishes to visit the site http://www.apple.com.au/index.html the ISP logs this request and its results for billing purposes via a proxy. Your job is to write some billing software for this Internet Service provider using any scripting language you feel comfortable with i.e. Python, Perl or Shell (if you want you can use C++). All user requests are stored in a log file at the ISP called proxy.log with one user request to a line. Considering the above request the resulting line in the log file would be 1184813281.056 0.170 137.157.60.46 200 1830 GET http://www.apple.com.au/index.html “text/html” For this task the most important columns are; a) Column 3 represents the IP address of the user. Each user has a unique IP address. For this assignment users will be represented by IP address. b) Column 4 is the HTTP response code. A value of 200 means the request for the resource was successful – anything else for the purpose of this assignment means it failure. c) Column 5 represents the size of the file. If the HTTP response code was…