On Tue, 18 Apr 2006 14:46:15 -0400, "Theodore Ts'o" <tytso@xxxxxxx> wrote: > On Tue, Apr 18, 2006 at 11:42:27AM -0400, Keith Moore wrote: > > > It smells remarkably like pathalias to me ;-) > > > > except that I'm not proposing that border routers do source routing, > > just that they map from PI identifiers to PA locators and prepend a > > header that causes the payload to be routed to the locator. > > And that sounds exactly like pathalias and what the Usenet/SMTP smart > routers did, yes? Hopefully though they wouldn't require as much CPU > power to calculate as pathalias database required --- as I recall Erik > Fair at Apple used a Cray for that purpose, because he didn't like > waiting.... :-) > Peter Honeyman optimized my original algorithm considerably; there's even a paper on it on my web page. There were two more fundamental problems that neither of us every really solved. One is relatively easy today: we didn't have good maps of connectivity for each site. Today, though, we have routing protocols that are supposed to disseminiate such data. Even now, though, there's a tension between physical connectivity and policy; we ran into that, too. The harder problem, though was metrics. Simple hop count gave bad results; bandwidth varied. (That said, the probability of uucp silently dropping the message was high enough that maybe we should have stayed with just that as a metric....) --Steven M. Bellovin, http://www.cs.columbia.edu/~smb _______________________________________________ Ietf@xxxxxxxx https://www1.ietf.org/mailman/listinfo/ietf