Encrypted desktop videoconferencing

[thad@hammerhead.com (Thaddeus J. Beier)]

A friend of mine works for a large input-device company, and they are looking
to get into the desktop videoconferencing business.  Their current business 
is extremely competitive on price, and they'd like to do something in
desktop videoconferencing that would distinguish them from everybody else.
Naturally, I suggested cryptography.

I have always thought that the biggest problem introducing crypto to
phone conversations was the large amount of cpu speed and software complexity
to digitize the audio; that adding the crypto code is relatively minor.
Certainly RC4 and IDEA for instance, run very fast.  In videoconferencing
applications, this audio compression is already being done, so adding
the crypto should be almost free.

Well, except for licensing costs.  I'd really like to use Diffie-Hellman
to negotiate a key.  Does anyone know how much it would cost to license
that from PKP?  I'd expect that there would be a one time fee, plus
a per-copy-sold fee.

Does anybody know - and if so, can they say - if anybody else has added
or is adding cryptography to their videoconferencing systems?  It seems
like such a killer ap that I must be overlooking something.

thad
-- Thaddeus Beier                   email:  thad@hammerhead.com
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