daemon@decwrl.UUCP (02/08/84)
From: castor::covert (John Covert)
Of course we want smart routing on the uucp network. But is it smart to
strip off pathnames that were explicitly specified when no domains are
present in the address?
Unless each machine that does name-stripping knows the domain space of
each node-name it strips off, misrouting can occur if gateways have
been crossed. How else can a name-stripper know which of the two nodes
named vortex is the real destination?
Smart routing should be truly smart, and not sophomoric. If the next
node specified in the path is not a communicating site, then a path-aliasing
can be done. Otherwise the specified path should be taken.
Once domains are fully implemented then smarter things can be done. Until
then, the path contains information which is dangerous to remove.
John Covert ...{ucbvax,allegra,decvax}!decwrl!rhea!castor!covertjmcg@decvax.UUCP (Jim McGinness) (02/19/84)
As perpetrator of the path improver in use on decvax, sophomoric as it may be, I feel compelled to say a few words in its defense. Under the circumstances, it's probably just as well that I cannot remember who first suggested this method. The path improver short circuits paths containing a uucp neighbor. For example, the path "siteA!siteB!siteC!user" is truncated to "siteC!user" if decvax has talked to siteC recently. Uucp (not just our version) keeps a stats file containing, for each site, the time of the most recent conversation or transfer. The important qualities of this method are that it is local, automatic, fairly safe, and uniform. All of the information needed is available on the machine doing the routing. There is no database to be collected and maintained. Mail will not be mis-directed along paths that have fallen inactive nor redirected into loops. If everyone used it, it would work even better. It does have failings. If it finds "vortex" in the path, then that piece of mail will go to LA rather than to the E-net. If someone sends mail on a long loop to probe a path or provoke a poll, it will get bounced at decvax rather than having the desired effect. It doesn't save us any money, just that of those sites we trim out of paths. Jim McGinness decvax!jmcg Digital Equipment Corp. (603)844-5703 MKO2-1/H10 Merrimack, NH, 03054