sendmail can lose forwarded mail - (nf)
rpw3 at fortune.UUCP
rpw3 at fortune.UUCP
Mon Dec 19 19:02:08 AEST 1983
#R:vax4:-125600:fortune:2000007:000:1249
fortune!rpw3 Dec 19 00:00:00 1983
Hmmmm... the infinite loop problem. I have two suggestions, neither of
which may be ultimately useful becasue implementing them might break
too much old software, but...
1. Yell, scream, demand, insist that systems supply guaranteed universally
unique I.D.'s on messages. Then you can at least detect loops at the
cost of caching "recently" seen I.D.'s). [One of the main reasons
Ethernet has 48 bit addresses, BTW]
2. Having done #1, look at the so-called "hot potato" routing algorithms
(and friends) that were popular a few years back (especially in
military work). In particular, there was a PhD thesis by a guy named
Tajibnakis (sp?) at Univ. Michigan which analyzed an algorithm which
guaranteed that every site would see every message and no link would
see it more than twice. Yea, I know that's better suited to USENET
ans BB's than to mail, but the real point is: Go back and dig up
some of the old store-and-fwd routing literature. An awful lot was
done on that before ARPAnet-style (fully connected all the time)
became popular.
Rob Warnock
UUCP: {sri-unix,amd70,hpda,harpo,ihnp4,allegra}!fortune!rpw3
DDD: (415)595-8444
USPS: Fortune Systems Corp, 101 Twin Dolphins Drive, Redwood City, CA 94065
More information about the Comp.bugs.4bsd.ucb-fixes
mailing list