[LINK] CNN, Octoshape and Obama

[Richard Chirgwin]

Karl Auer wrote:
> On Mon, 2009-02-09 at 08:50 +1100, Roger Clarke wrote:
>   
>>       But even that is sufficient to enable informed consent.
>>       e.g.
>>       "the app will use some of your disk-space and bandwidth to deliver
>>       parts of the video and audio stream to other end users of the
>>       Software"
>>     
>
> I don't know for sure, but it seems to me that the only way Skype can
> work is to use (abuse?) the good offices of people with non-NAT
> connections. Yet I know I was never informed (or at least not in a way
> that I noticed) about that possibility - although since my client is
> NATted maybe there was no need.
>
> Regards, K.
>   
I think, from reading various analyses of the Skype protocol, that it's
designed to work around NAT. It has, I think, a proprietary
equivalent to STUN, so that it can traverse the firewall.

Eg:
<http://www1.cs.columbia.edu/~library/TR-repository/reports/reports-2004/cucs-039-04.pdf>

Cheers,
RC