Frothing remailers - an immodest proposal

[Hal]

One point re remailer reliability:  Even though in my discussions with
Nathan I did not really agree with his suggestion to have remailers check
signatures on incoming messages, actually Chaum did propose something
similar in his 1981 paper.

He would have each remailer sign the batch of messages it outputs each
cycle.  (Chaum's remailers used a straight batching approach.)  The idea,
as I recall, was to allow a remailer to prove that it had not engaged in
a denial-of-service attack by purposely dropping some message into the
bit bucket.  If some customer put his message in here and it didn't ever
come out over there, I guess the remailer could prove that it didn't lose
the message by showing its signed batch.  I'm not clear on the details
though.  Anyway, here is an area where message signing and reliability
have some intersection.

Hal