Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!samsung!munnari.oz.au!cs.mu.OZ.AU!kre From: kre@cs.mu.OZ.AU (Robert Elz) Newsgroups: comp.protocols.tcp-ip.domains Subject: Re: Proposed extensions to MX records. Message-ID: Date: 30 Mar 91 12:48:21 GMT References: <1991Mar28.170144.8370@mp.cs.niu.edu> <1991Mar28.182232.13467@agate.berkeley.edu> Sender: news@cs.mu.oz.au Lines: 29 cliff@garnet.berkeley.edu (Cliff Frost) writes: >This proposal implies using Domain Names for routing decisions. It's always >been my understanding that a DNS name implies nothing at all about routing >(for IP or mail or anything else). Is this no longer true? Its true in theory - in practice many DNS domains are isomorphic with routing areas. Its that practical truth, combined with the ability to make use of it without making any real change to the DNS system that inspired this proposal I believe. That is, for very little cost, a scheme can be implemented that would be of use to many sites, though there's no doubt that it would not be "complete" in any sense, nor would it be able to handle any arbitrary situation. >Where I'm more confused is in the area of geographic "ISO-ish" domain names. >Is a name that ends in ".AU" absolultely required to refer to a host that >is physically in Australia? It is not required, formally or otherwise. What's more, even if it were, that would not imply anything about routing, there are hosts in the AU domain (which happen to be in Australia) that send IP packets to each other via the US (entering at the west coast, crossing NSFnet, and exiting in the north east). (That is, from any regular AARNet host, to one on one multi-national company's IP net that happens to contact the world's research nets in north east US). kre