La Trobe University, Bendigo

Department of Information Technology

INT21CN: Computer Networks

Assignment 3, 2002

Your task in this assignment is to investigate ONE ONLY of the following topics in computer network architecture, and submit a report on your findings. Most of the questions are fairly "open-ended", so it'll be easy to do too much! Keep reminding yourself that you only have to write a maximum of 2000 words for the assignment.

Note also that additional topics might appear on this page as they are suggested to me. It could be worth checking back regularly if you don't like any of those given below.

• One of the biggest problems faced by Internet users is that of Spam -- unsolicited commercial/bulk email. The spammers use a great number of techniques to hide their identity, but much can be discovered by a few simple tricks. Firstly, it is usually possible to examine the Received: headers of a spam message and discover where it was relayed -- you can then complain to the relay site's administrator. Secondly, if the relay site doesn't respond you can use a tool like traceroute to discover his "upstream ISP" and complain to the admin of that site. Using some real spam email which has been sent to you, discover and document:
  1. whether the relay or originating host can be identified, and whether complaining to postmaster at that site has any effect, and

  2. Whether upstream ISPs revealed by traceroute are useful in the fight against spam, and finally

  3. How you can configure your mail software to filter spam coming from known relay sites.

• A local Bendigo business desires a full-time Internet connection, to enable them to run a Web and email server. You have been engaged as a consultant to advise them on their options, and to suggest the best mix of technology and products to serve their purpose. You may assume that speed, whilst always obviously important, is not their main concern. See if you can come up with some "real-world numbers" for pricing, without doing an excessive amount of work. This question is not> about hardware and software. You are not to write about how to set it up, what sort of computers would be required, what software they should run, etc. Your assignment is to present options for the "Basic Carriage Service" and the ISP costs, for a business which will, presumably, be running a Web server and an email gateway on a full-time connection. That's it. You must use Real World™ numbers, and there must be some comparative component. And yes, it will be difficult to find this information

• Investigate steganography, and in particular how it relates to encryption and the Internet. This is a fun topic, because you should discover lots of interesting software and applications. Try some of them, and document the results! One absolutely fascinating aspect of this topic which has appeard in recent months has been the use of "pattern analysis" to discover whether a stego message exists in an object, by looking for the characteristic "telltale" signs generated by common stego packages. See if you can discover how this works. Your report should have a reasonable practical component.

• Investigate the use of PGP (and/or GnuPG) as a practical encryption tool, suitable for everyday use in the modern email environment. Download a recent package and install as a plug-in in your normal email software. Document the effort required to create a key pair, distribute your public key, and exchange encyrpted and/or signed emails with others. It's obvious that you'll have to work with someone else to manage this. Shared assignments are possible here, but I'd prefer if you each used (at the least) a different email package, and submitted separate assignment reports.

• Use tkined to build a network management system for the Bendigo campus, monitoring most of the interesting pieces of equipment in the campus network. You should submit the ".tki" file for your system, along with a brief description of what it does, and how it does it, so that we can run it and check its operation. Obviously this question is only relevant to people who are taking the subject on campus, although if you're located somewhere with an interesting network perhaps you could set up tkined and use it there. Or perhaps you could use one of the many other SNMP packages available, see below.

• Build a useful "Network Operations Console" using the freely available SNIPS software which is installed on our Unix systems. Extra information as for previous question.

• The best (free) SNMP package for Unix is tkined. There are many other SNMP-based network monitoring packages in existence, particularly for Windows systems, although there are a few for Macs as well. Discover one (or more) such packages (such as Netsaint), install them on your home system(s) and report on their usefulness.

• Discover what the pathchar software package does by installing it on your computer and testing it. Report briefly on how it does its work, and your experience with it.

This assignment carries 20% of your mark for Computer Networks.

Due Date:7th June, 2002 (end of semester 1)

Lecturer: Phil Scott, 5444 7277, p.scott@latrobe.edu.au.