🚀 go-pugleaf

I think demonstrating the delivery of postings is overkill, as well as
being difficult.  Given a moderator for a newsgroup, one could implement
a simpler scheme as follows:

Let	M(n) be the n-th posting to the group
	D(n) be a digest (e.g. by MD5) of M(n)

When the moderator accepts a posting M(n+1), he appends D(n) to it, signs
the result, and returns a copy to the poster.

The poster is now in a position to prove that he submitted the successor
to M(n).  In addition, any reader who receives M(n+2) without receiving
M(n+1) will detect the omission.  (What he does about this is up to him,
but at least he knows about the problem.)

If the moderator signs two different postings as successors to M(n), and
either author gets ahold of a signed copy of the other posting, then he
is in a position to discredit the moderator.  If there is any means (even
non-deterministic) of making public signed postings (e.g. posting them to
other newsgroups, uploading them to random BBS's, printing them in the
Personals columns of newspapers, etc.), then such inconsistencies are
subject to detection.

Furthermore, if the moderator does fork the newsgroup in such a fashion,
the appended digests prevent seamless merging of the resulting groups.

It remains the case that the moderator can refuse or alter a submission
to the group, but this is traditionally one of his prerogatives.  (Note
that having the moderator sign D(n) without seeing M(n) is unnacceptable.)
If he alters or fails to sign it, the poster will of course know.  If he
signs and suppresses it, he compromises himself as soon as he signs the
next posting.  Of course, he can refuse all postings thereafter, but this
is again his prerogative.

Finally, a moderator must still be chosen; but now his performance (or,
rather, his performance modified by the reliability of the newsfeed) can
be effectively monitored.  (If you miss a posting, I guess you query
archive servers and/or the moderator for it.  If they don't reply, I
guess you start complaining in other newsgroups.  If every moderator
refuses your postings, I guess you get paranoid...)

--
Jeff Keller <keller@cse.ucsc.edu>	CIS Board, UCSC
"If X is the answer, what was the question?" --David Fuller