managing and protecting nyms...

[Morlock Elloi]

The cost of breaking even bad crypto can be quite high.

If you just take, for example, DES, and change all S boxes to different random values, then provide these values as pre-arranged secret key to the other party, and use them only with this single correspondent, and keep your algorithm secret, while using a single 1-character key "a" through "5" depending on the day of month, how long do you think it will take someone to break the cipher and how much would it cost?

First they have to get enough text for correlation and differential attacks. Then they are starting with quite long 2K-bit S boxes that need to be inferred. It would take a brilliant analyst more then few days to break this. Few days of a brilliant analyst at Ft. Mead are very expensive, when you include all the overhead. Say $0.1-0.5M.

Compare this cost to the cost of breaking a massively used crypto algorithm with a backdoor.






> Isn't that the procedural equivalent though of saying "you
> should always
> keep your cryptographic algorithm secret and only disclose
> an algorithm
> as a ploy to deceive"?