On Mar 18, 2008, at 11:31 AM, Frank Ellermann wrote: > Steve Atkins wrote: > >> As the hostname being checked is on the RHS of an email address >> there must be an A record or MX record for it, in order for it to >> be... operationally relevant, anyway. > > JFTR, if all goes well 2821bis will explicitly add AAAA. This does > not mean that "AAAA only" is an operationally good idea today, but > the "MX required" faction was hopelessly outnumbered for 2821bis.
What justifications were given for including AAAA records as SMTP discovery records in the face of today's level of abuse? Nevertheless, this outcome does not prevent a requirement for MX records when publishing DKIM policy. Only MX records are required to be at the email-address domain and are used specifically by SMTP. Having the MX record to qualifyuse of email policy can reduce the number of transactions required for policy discovery, and offers a practical means to disavow use of DKIM/SMTP. -Doug _______________________________________________ NOTE WELL: This list operates according to http://mipassoc.org/dkim/ietf-list-rules.html
