La Trobe University, Bendigo

Department of Information Technology

INT21CN: Computer Networks

Assignment 3, 2003

Your task in this assignment is to investigate ONE ONLY of the following topics in computer network architecture, and submit a report/essay 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. You must also remember to correctly reference your information sources!

Note also that additional topics might appear on this page as they are suggested to us. 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 or abuse at that site has any effect, and

  2. Whether its worth the trouble to inform upstream ISPs revealed by traceroute in the fight against spam.

• The previous question related to "proactive" approaches to spam. For many Internet users the simplest solution is simply to discard spam emails. This can be automated/assisted by "intelligent" email filters.
  1. Discover what you can about approaches taken to email spam filtering. In particular, what can you learn about "Bayesian Spam Filters"? Are such filters readily available, and how well do they perform? Are there better approaches -- for example, how do such filters compare with (eg) whitelist/blacklist approaches? With other adapative filter technologies?

  2. Can you configure your own email software (whatever it is that you use on a regular basis) to discard spam, based on the filtering technologies you have discovered in your research for this question? As for the previous question, demonstrate its operation on real spam email which has been sent to you

• You have been approached (as a computer networking expert) by a local business (or community organisation, or whatever) who desire to get their business "onto the Web", with their own domain name. The name is to be registered in the either of the .com.au or .org.au domains, so (for example) we might use dodgybros.com.au as the domain name. Write a report explaining the steps (and costs) involved in registering the domain name, contacting with a Web hosting service and getting their pages "online". You should be sure to mention some technical aspects of how the DNS is to be configured.

• A local Bendigo business desires a full-time Internet connection, to enable them to run their own 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 absolutely not about hardware and software beyond that needed for the actual connection to the ISP, such as access routers, etc. You are not to write about how to set up servers, 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. NB: you also do not have to address issues of domain name registration, delegation, etc -- see previous question if these topics interest you.

• 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/usual 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. If you're intending to submit your assignment by email, I would like it signed with your private key and a copy of your public key handed to me as well so I can verify its source. You might care to comment on the usefulness of these technologies in typical Web-based email systems.

• 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 single ".tki" file for your monitoring 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.

• The best (free) SNMP package for Unix is widely believed to be 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 Nagios), install them on your home system(s) and report on their usefulness.

• One of the more "interesting" developments in recent times has been the ENUM technology for integrating aspects of Internet addressing with the existing telephone numbering system. This is an immensely complex system, with serious privacy implications. Your task: in the limited number of words allowed for in this essay, briefly describe the ENUM proposal, and outline the privacy concerns which are related to its implementation.

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

Due Date:6th June, 2003 (end of semester 1)

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