Communication, Codes and Cyphers

HON 400, Section 005

Welcome to the course homepage for Communication, Codes and Cyphers (HON 400), section 005, Spring 2002. If you are a student in this class you should check this site frequently for new information.

The Illegal Prime

The prime number described at The Prime Pages may constitute an illegal circumvention device under the Digital Millennium Copyright Act (DMCA), since if it is decompressed with gzip it becomes a program for breaking the encryption system on DVDs.

For other examples, see the Gallery of CSS Descramblers compiled by Dr. David S. Touretzky, a computer science professor at Carnegie Mellon University and opponent of the DMCA. (CSS stands for Content Scrambling Scheme, and is the standard for DVD encryption.) Look at the examples and see what you think - where is the line between free speech and computer software?

Patents

For a well-researched, easily understood article about patents and patent law, read James Gleick's Patently Absurd. I used this article as a primary source for lectures.

The US Patent and Trademark Office has more detailed information about patents and other intellectual property.

Patents on compression algorithms can be found in the comp.compression FAQ. This FAQ is also a good source for brief explanations of algorithms, file formats, and other issues related to compression technology. RSA Security have a FAQ which lists some significant encryption patents.

Notes

Notes for the course are available online.