And which of the two of you did I hear volunteer to start writing a coherent and unified "best practices" I-D? Please take this off the list and start writing.
john --On Wednesday, 16 April, 2008 22:30 +0100 Sabahattin Gucukoglu <[EMAIL PROTECTED]> wrote: > > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > Hi Frank, > > On 16 Apr 2008 at 20:46, Frank Ellermann > <[EMAIL PROTECTED]> said: > >> "Tony Finch" wrote: >> >> > I doubt that it makes sense to accept email from >> > [EMAIL PROTECTED] on a system that can only >> > communicate with IPv4 addresses. >> >> In stark contrast to Ned's view I think that you >> MUST reject such mails - unless you can guarantee >> delivery without auto-response (no NDR, no DSN, >> no MDN, no vacation, no forward, in essence an >> empty reverse-path, near to rewrite MAIL FROM:<>) > > No, I don't agree. Your only real obligation is to ensure > that your output relay doesn't attempt a delivery and so > waste resources when it can't do it by simply guaranteeing > that IPv6 hosts aren't considered in email routing at time of > delivery (EG worst case is a double-bounce listing "No data" > as reason because the resolver routines have ignored the IPv6 > addresses, if double-bounces were enabled - and they should > be!). That doesn't mean not accepting mail from IPv6-only > hosts, any more than it means not accepting mail from an > invalid mailbox. IMHO, it's your responsibility to ensure > that mail can and will be accepted and to make sure that it > will be delivered so that the minimal number of DSNs/whatever > have to be generated to accomodate your configuration problems > under whatever circumstance. It is less wise to depend on a > sender check that doesn't make sense semantically (there > never has been and never will be a requirement in a spec > enforcing it, and for good reason, even if it makes sense for > policy) and which is only really useful as a feeble antispam > check nowadays anyway in these days of deliberate DSN disposal. > >> Same idea as in EAI, after a reject "the sender >> can make another plan". After accepting it the >> IPv6-only mail vanished in a black hole for all >> non-trivial cases. > > Cheers, > Sabahattin > > - -- > Sabahattin Gucukoglu > <mail<at>sabahattin<dash>gucukoglu<dot>com> Address > harvesters, snag this: [EMAIL PROTECTED] > Phone: +44 20 88008915 > Mobile: +44 7986 053399 > http://sabahattin-gucukoglu.com/ > > > -----BEGIN PGP SIGNATURE----- > Version: PGP 8 > Comment: QDPGP - http://community.wow.net/grt/qdpgp.html > > iQA/AwUBSAZv2iNEOmEWtR2TEQLidgCgk0IXZEEBqCfv9cXv1S652LVYTiUAn1 > bT wv9u+hrPwyAmpqq1p98Rkph6 > =75hu > -----END PGP SIGNATURE----- >
