signalling level voip privacy & p2p (Re: [p2p-hackers] Is P2P SIP Poised to Out-Hype Skype?)

[coderman]

On 8/23/05, Adam Back <adam at cypherspace.org> wrote:
> ...
> An interesting area tho I think for signalling because it is low
> bandwidth, and somewhat tolerant of latency is to use concepts like
> PIR (private information retrieval), where it is possible for example
> to implement computationally secure single database PIR.

the pynchon gate is a PIR technique that may be of interest:
  http://www.abditum.com/~rabbi/pynchon.pdf

also, reencryption mix networks may be useful for low bandwidth
signalling communication.  (though you significantly raise bandwidth
requirements as you scale such a network)
  http://www.syverson.org/univrenc-ctrsa.pdf

best regards,