Path: utzoo!utgpu!attcan!uunet!husc6!ukma!cwjcc!hal!ane From: ane@hal.UUCP (Aydin "Bif" Edguer) Newsgroups: comp.mail.uucp Subject: Re: active rerouting Message-ID: <290@hal.UUCP> Date: 29 Sep 88 12:17:54 GMT References: <4740@b-tech.UUCP> <4747@b-tech.UUCP> <4748@b-tech.UUCP> <6581@chinet.UUCP> <2105@edsews.EDS.COM> <12604@ncoast.UUCP> Reply-To: ane@hal.cwru.edu (Aydin "Bif" Edguer) Organization: Biometry Computing Facility Lines: 58 In article <12604@ncoast.UUCP> allbery@ncoast.UUCP (Brandon S. Allbery) writes: >As quoted from <2105@edsews.EDS.COM> by roberts@edsews.EDS.COM (Ted Roberts): >+--------------- >| In article <6581@chinet.UUCP>, les@chinet.UUCP (Leslie Mikesell) writes: >| > >| > Suppose >| > you want siteC to route siteA!siteB!siteC!domain.dom!user or >| > siteA!siteB!siteC!user@domain.dom. >| >| These are not the same thing. The first route would send to siteA, then >| siteB, then siteC and siteC would route to user@domain.dom which they >| would know how to do since they know how to resolve domain addresses >| (you hope:-). The second would attempt to send to domain.dom, then to >| siteA, then to siteB, then to site C, then to user. This is because the >| "@" syntax takes precedence over the "!" syntax. >+--------------- >WRONG!!! "@" and "!" are used by different networks -- there is NO defined >precedence between them! (You're comparing apples to oranges.) UUCP sites >give "!" precedence, Internet domain mailers give "@" precedence. BZZZ! Wrong WRONG :-) All internet sites should give "@" precedence. All RFC976 compliant UUCP sites should give "@" precedence. All lowlife, noncompliant UUCP sites give ! precedence :-) Here is the relevant quote from RFC976: "UUCP Mail Interchange Format Standard 2.1 Hybrid Addresses In conformance with RFC-822 and the AT&T Message Transfer Architecture, we recommand that any host that accepts hybrid addresses apply the (a!b)@c.d interpretation." 5. Summary The originating site should ensure that the addresses conform to RFC-822, since no requirement is placed on forwarding sites or gateways to transform addresses into legal RFC-822 format. > On ncoast (a UUCP system) "!" has precedence. Our neighbor "hal" gives "@" > precedence because they are on the Internet. This can be quite useful; if I > want to send mail across the Internet I can mail to hal!foo@bar.COM, thus > overriding the UUCP route (which may well be slower) that smail would give > me from a straight "foo@bar.COM". Yes. But the proper way to do this is to send to hal!bar.COM!foo. WHENEVER POSSIBLE, use non-ambiguous paths (only "!"'s or "@"'s, not both). I promise to correct the problem if it does not attempt delivery to foo@bar.com when given the path hal!bar.com!foo. (note: I make no guarantees it will actually get there) I am not yet a class 3 site (I do not currently use the pathalias database) but I do try to conform to the rest of the RFC976 standard. > Things get even more interesting when you try to apply your rules to a > DecNet network or to the Bitnet as well (on Decnet, does "::" have > precedence above or below "@"? How about "!"? Does Decnet even *care* what > the relative precedence of "!" and "@" is?) If the site is DECnet \(tm ONLY then it is welcome to do anything it wants (including eating fudge brownies whenever it sees an "@") but if it is on the Internet, then it is supposed to be RFC822 compliant and RFC822 says that "@" has precedence! The information to the left of the "@" is local information. Aydin Edguer Case Western Reserve University