On 2012-11-21 4:44 PM, Ted Lemon wrote: > ... Aside from this quibble, I think the document is useful and should > be published.
my quibble is different. ipv6 is bringing some tough love to the consumer-facing edge. the fact that ISP's auto-populated the IPv4 PTR tree made it impossible for mail server operators to distinguish between consumer grade and business grade internet connections. since consumer grade connectees should really not be connecting to SMTP servers on other networks, there's been a great deal of work to find all of the common auto-populated PTR naming patterns in use anywhere in the world, in order to reject off-net e-mail from consumer grade connections. this work is inefficient, ineffective, painful even when correct, and often wrong. there are some excellent reasons not to use PTR RR records for this purpose, starting with good security practices and continuing through good engineering practices. nevertheless this is a pre-existing property of the existing server plant, and even if server operators were willing to give it up, the tail would be very long. i'm going to treat this as an unavoidable universal mistake that all of us will have to live with, forever, period. network operators should provide PTR RR's for specific addresses which have real names. the inability due to IPv6's richness of address space to provide auto-naming for PTR's does not to me, a problem statement make. paul -- "It seems like the rules for automagic completion of incomplete names typed into browsers are going to start to look like those for the game of fizbin." --rick jones _______________________________________________ DNSOP mailing list DNSOP@ietf.org https://www.ietf.org/mailman/listinfo/dnsop
