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Re: Man in the middle attacks

At 10:20 3/6/96, Bruce Zambini wrote:
>On Tue, 5 Mar 1996, Carl Ellison wrote:
>> if you have Bob locked in Eve's attic, does Bob exist apart from [Bob,Eve]?

>However, if you've met Bob in person once or twice, especially BEFORE you
>met Bob online, there is a very clear difference.

Yes!  If you've met Bob in person, then you have a body of common knowledge
that most likely can be converted to a shared secret.  That shared secret,
in turn, can be used to verify that there is no eavesdropper.  This
in-person meeting is the second channel which defeats Eve.

The thing which amazes me is how fragile the MITM attack is for all the
attention it gets.

|Carl M. Ellison          cme@cybercash.com   http://www.clark.net/pub/cme |
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