Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!cs.utexas.edu!uunet!mcvax!ukc!dcl-cs!aber-cs!pcg From: pcg@aber-cs.UUCP (Piercarlo Grandi) Newsgroups: comp.mail.sendmail Subject: Re: Short-circuiting a route Keywords: sendmail, smail, domain names Message-ID: <1047@aber-cs.UUCP> Date: 1 Jul 89 13:05:57 GMT Reply-To: pcg@cs.aber.ac.uk (Piercarlo Grandi) Organization: Dept of CS, UCW Aberystwyth (Disclaimer: my statements are purely personal) Lines: 36 In article lear@NET.BIO.NET (Eliot Lear) writes: > Domainization is only a scheme to generate reliably unique names, not > to give routing hints; these should be based on maps. And you should > never try to second guess somebody's else's maps... I'm not sure who is missing the point... If a name is unique, then one should be able to short circuit to it, And generate interesting mail loops... Again, names may be relative or absolute, and routing may be source or dynamic, but the two issues are TOTALLY unrelated. Relative names (a la UUCP net) may LOOK like routes, but they need not be; conversely absolute names don't imply anything about routing. and then use routing information, as declared SOMEHOW. SOMEHOW can be one of two methods: o If one is not connected to the Internet, one can use the map data. o If one is connected to the Internet, there are a number of standards (rfc974,rfc103[4,5]) to determine what Internet host to deliver a message. When you do anything other than prepend to a route, you are second guessing the original router, and to do that reliably you need to know that your maps are better (whether Internet or not). This is hard... At the very least it requires a distributed database update algorithm, and even the Internet one does fail occasionally. -- Piercarlo "Peter" Grandi | ARPA: pcg%cs.aber.ac.uk@nsfnet-relay.ac.uk Dept of CS, UCW Aberystwyth | UUCP: ...!mcvax!ukc!aber-cs!pcg Penglais, Aberystwyth SY23 3BZ, UK | INET: pcg@cs.aber.ac.uk