Hi > An other problem will arise if ISPs force there customers to use > there own SMTP relay server because they are blocking outbound > traffic to tcp/25. So this customers can not use the SMTP relay > server of there domain hosting provider with SMTP Auth (and > hopefully TLS) on tcp/25.
Valid point. One of the ideas we came up with was to provide customers with a mail address they could send a mail to. A script would then parse the headers and add the server(s) found to the SPF record. Only caveat: some ISPs use more than one IP address for outbound mail so you can never be sure you got all servers in your list. That's why you all need to adopt SPF. There is a "include" directive in SPF which would allow us to include, say bluewin's or tiscali's outbound mailservers, _given that they provide these records_. http://spf.pobox.com/mechanisms.html#include > I see still to many problems with systems like SPF, to much work > for only a little advantage. Because if big domains like gmx or > yahoo just put 0.0.0.0/0 in the SPF DNS entry it is just useless. Consider it a stub record - as much as SA 3.0's implementation of SPF is .. well .. not yet perfect :) The wider SPF has been adopted, the more sense it will make to support it. Or do you know of any other technology which would allow you to do what SPF does? Use your imagination - tell customers they can protect their domains from abuse when they enable SPF. That's another selling point! -- Kind Regards Daniel Lorch Positive Feedback Cycle Engineer Hostpoint GmbH � � � �| The Data Residence � �| Z�rcherstrasse 2 � � �| 8640 Rapperswil � � � | Schweiz Tel �+41 55 220 0404 �| Fax �+41 55 220 0409 �| www.hostpoint.ch _______________________________________________ swinog mailing list [EMAIL PROTECTED] http://lists.init7.net/cgi-bin/mailman/listinfo/swinog
