Re: Anti-spyware at the Gateway

Volker Birk wrote:
> Sebastian Gottschalk <seppi@seppig.de> wrote:
>> Volker Birk wrote:
>>> Somebody. <somebody.@nospam.russdoucet.com> wrote:
>>>> Oh wait, I forgot, tunnels are impossible to detect. Never mind.
>>> You have a problem with logic. No-one said, that it is impossible to
>>> detect a tunnel.
>> But I'm saying so.
>
> Then you're wrong.
>
>> Using public key cryptography one can create a tunnel
>> that provably can't be differed from a normal session ID transfer.
>
> And knowing how it is done means being able to detect.

Assuming the session ID transfer is a fully normal and trusted activtiy
(f.e. logging in at nytimes.com and reading some articles)and the
session ID is a pseudorandom value, you can create a covert channel with
bandwidth efficiency 1/n that is as hard to detect as it is to break
either a chosen n-bit symmetric cipher or RSA of any length.
Received on Mon May 1 00:57:31 2006