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Today we first worked on some bitstream problems [PDF|PS|TeX]. We spent a total of about 40 minutes on them. I think some of the students understood the point. We put our chairs all in a circle, and Mr. Radomirovic and I walked around and tried to help people. It was somewhat slow going, especially finding the bitstream for the last exercise (with a depth). I had prepared solutions, which was fortunate. Part of the success in decrypting the Venona messages was misuse of the one-time pad: agents sometimes reused their keys. That's easy to understand, because distribution of key material was very difficult. Answers together with comments (the last 3 pages of the handout previously referenced) were handed out after our work.

Then we had the European Union report. This was o.k., not great. Some of the reasons are given here. We discussed what authorities say they will do compared to what is actually done. I tried to discuss the eavesdropping problem realistically, since the Echelon idea, currently a topic of scandal in some European circles, came up.

I gave out the "Aliens" bitstream homework [PDF|PS|TeX]. Since some students were absent, I began to put the homework on the web. Again, for these exercises in class and for this homework assignment, some simple Maple routines were written to make life easier.

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