tneff@bfmny0.UUCP (Tom Neff) (08/26/89)
The question is: whether 'tis nobler in the mail to let some other smart host do thy routing for thee, knowing for thyself only the rump end of thine intended recipient's net address, or whether to take arms against the little twisty passages of net topology and, by running pathalias(1), conquer them. The answer -- AN answer, MY answer -- is that it depends heavily on what kind of site you are. If you are a leaf site, taking everything from and routing everything to one or two major well connected sites, then you might as let the big guys do the routing for you. They employ sysadmins and presumably update the maps regularly, which may be more of a responsibility than your site can afford. And since everything goes through them anyway, you can't cost the next an extra dime by relying on them for routing. On the other hand if you are a well connected site yourself, with links to several other well connected sites of net wide popularity, then you or your sysadmin owe it to the net to maintain up to date routing maps and use them. Otherwise it costs the net extra money to forward things from B to C to D to E when you could have gone straight from A to E. If you are a common or garden user on a largish machine which has the latter mentioned responsibility of correct routing, it does not mean that you yourself need know the correct path. Your site should run routing software like pathalias(1) to handle correctly addresses you specify. Only if your intended destination host is off the maps should you need to supply bang ! information yourself. The good news is that even if you are a leaf site pathalias runs OK and helps set things up properly. There is a facility in "smail" and pathalias called "smart-host" which says: if a destination doesn't appear on my local detailed map (such as you might have to route mail through a few departmental computers), forward to to machine X and let it figure things out. The advantage to this method for a leaf site is that you only need to change your map data when you add a new direct feed or otherwise change your local topology. The monthly torrent of new sites and address changes across the wider net.world can go right on but you needn't rerun pathalias or download all that data. -- "We walked on the moon -- (( Tom Neff you be polite" )) tneff@bfmny0.UU.NET