Re: post-doomsday computing

From: stanislav shalunov (shalunov_at_internet2.edu)
Date: 07/22/03 

Date: 22 Jul 2003 15:22:42 -0400

Erik Max Francis <max@alcyone.com> writes:

> [...] A one time pad generated from a cryptographically strong
> pseudorandom number generator will likely be cryptographically
> strong, but possibly not unbreakable.

That is not a one-time pad. That is simply a stream cipher. It may
be more or less secure (usually, people who call stream ciphers
one-time pads are also using ridiculously weak stream ciphers). A
stream cipher of that sort shall never have provable
information-theory security of a one-time pad.

> Whether the latter even deserves the term "one time pad" is a
> separate semantic question; as an existence proof, I see quite a few
> Web references referring to "one time pads" using "cryptographically
> strong pseudorandom number generators."

``Virtual one-time pads,'' ``patented,'' and ``proprietary''
encryption schemes, and all? Why should we pay any attention to
crackpots and snake oil salesman when they try to hijack a
well-established term? 

-- 
Stanislav Shalunov		http://www.internet2.edu/~shalunov/
This message is designed to be viewed at sea level.

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