Manifest: Monday 18 September 2000

Assignments Due
11:59pm tonight	Projects Preliminary Proposal
27 September	Problem Set 2

Readings
Read before 20 September:

• Ron Rivest, Adi Shamir and Len Adleman. A Method for Obtaining Digital Signatures and Public-Key Cryptosystems, Communications of the ACM, Feb 1978. This is the original RSA paper. It is recommended that you read it in the Rotunda or one of the lawn gardens.
• Stallings, Chapter 7. You can read this anywhere.

Optional reading for more information: (see web version for links)

• Prophet of Privacy, Wired Magazine Feature on Whitfield Diffie. November 1994.
• Diffie-Hellman Key Exchange - A Non-Mathematician's Explanation
• Whitfield Diffie and Susan Landau, Privacy on the Line: The Politics of Wiretapping and Encryption, 1998.
• New York Times article on history of public-key cryptography, December 24, 1997.
• Ellis, Cocks and Williamson's original memos on non-secret encryption

Questions

• Why is key distribution important?
• What are some ways to distribute secret keys?
• What is a public-key cryptosystem?
• How does Diffie-Hellman key agreement work?

Useful Proof Methods
Proof by intimidation: "Trivial" or "obvious."
Proof by exhaustion: An issue or two of a journal devoted to your proof is useful.
Proof by omission: "The reader may easily supply the details", "The other 253 cases are analogous"
Proof by obfuscation: A long plotless sequence of true and/or meaningless syntactically related statements.
Proof by funding: How could three different government agencies be wrong?
Proof by lack of funding: How could anything funded by those bozos be correct?
Proof by democracy: A lot of people believe it's true: how could they all be wrong?
Proof by reference to inaccessible literature: The author cites a simple corollary of a theorem to be found in a privately circulated memoir of the Icelandic Philological Society, 1883. This works even better if the paper has never been translated from the original Icelandic.
Proof by vehement assertion: It is useful to have some kind of authority relation to the audience, so this is particularly useful in classroom settings.
Proof by vigorous handwaving: Works well in a classroom, seminar, or workshop setting.
Proof by cumbersome notation: Best done with access to at least four alphabets, special symbols, and the newest release of LaTeX.

Selected from http://www.ai.sri.com/~luong/research/proof.html.
None of these proof methods are suggested in CS551 problem sets.

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University of Virginia Department of Computer Science CS 551: Security and Privacy on the Internet

David Evans evans@virginia.edu