On Thu, Aug 30, 2001 at 09:14:46PM -0700, Tim May wrote: | A mixnet of the N extant remailers offers pretty damned good | untraceability. Needs some work on getting remailers more robust, but | the underlying nested encryption looks to be a formidable challenge for | Shin Bet to crack. http://anon.efga.org/Remailers lists about 35 Mixmasters and 45 type 1 remailers. An awful lot depends on what you mean by "pretty good untracability." For example, if you send a dozen messages from Alice to Bob, then I'd bet you can do an entry-exit correlation attack. It becomes harder if you add substantial cover traffic, but Kocher-esque reductions in the noise are very powerful. If Alice and Bob are smart spies, and use a different hotmail recieving address each time, then you get pretty good untracability, but that untracability comes as much from the one-off nature of the messages as the mix network between them. And, depending on how good I think Shin Bet is at traffic analysis, I'm not sure if I'd even draw attention to my messages by sending them through 1/40^5 remailers. Thats 28 or 29 bits with 5 hops. If you start looking at reliability, only half or so of the remailers have 99% reliability, although only 10 are below 95% which means either a smaller pool, or a need for redundancy, both of which reduce your security. Adam -- "It is seldom that liberty of any kind is lost all at once." -Hume