[Sipping] Re: draft-campen-sipping-stack-loop-detect-00, top route headers and spiraling

Byron,

Thanks for your responses. I think it would be worthwhile to include this information in your draft, it helps to make things explicit.
  Unfortunately, loop-detection actually doesn't solve the forking-loop exploit detailed in maxforwards-problems. Instead of a maxforwards^m level of amplification(m is the number of proxies involved), we still get well over an m! level of amplification. Robert Sparks worked it out to O(m^m), and I am not surprised (this of course only applies for cases where m < max-forwards). This is an improvement, but is still not acceptable. The only solution put forward so far  that seems to adequately reduce the damage caused by the forking loop exploit is the technique detailed in the max-breadth draft. 

I made a suggestion on the list the other day: keep a forking proxy from forwarding to an element which is already on the Via list, i.e. loop prevention rather than detection. You would still need both of course, since one cannot rely on other proxies having implemented this. I believe it could be a simple and effective solution, what do you think?

Regards,

Jeroen