nanog mailing list archives
Re: Outgoing SMTP Servers
From: Mark Andrews <marka () isc org>
Date: Thu, 27 Oct 2011 09:11:41 +1100
In message <op.v3y8xvo6tfhldh () rbeam xactional com>, "Ricky Beam" writes:
On Tue, 25 Oct 2011 15:52:46 -0400, Alex Harrowell <a.harrowell () gmail com> wrote:>Why do they do that?You'd have to ask them. Or more accurately, you'd need to ask their system integrator -- I've never seen an "in house" network run like that. (and for the record, they were charging for that shitty network access.) Bottom line: Blocking port 25 (smtp) is undesirable, but necessary for a modern consumer internet. (Translation: It f'ing works.) This is the ISP saying, "You aren't a mail *server*."
MTA == Mail Transfer Agent. You don't have to be a *server* to be a MTA. Blocking SMTP also prevents your customers running encrypted mail sessions to prevent nosy ISP's and others looking at what they are sending. With DNSSEC now being deployed and DANE being standardised, running a SMTP session with STARTTLS is being a reality. Now most people don't care about this but you shouldn't have to get a business grade service just to have secure email sessions and if you want to run a SMTP server to do that you are not changing the amount of traffic going over the connection so why the hell should a ISP care. IMAP, POP, SMTP all have about the same overhead for inbound email.
MUA's (mail clients) should only be connecting to specified MSA's or MTA's (mail *servers*). They should never be connecting to random MTA's (presumably for direct delivery, which is the job of an MTA not MUA.) The only people who can effectively police this is the ISP.
Total utter BS.
Individual mail server admins and RBL maintainers can only guess and be reactionary, which is often wrong, still lets spam through, and becomes stale rather quickly. --Ricky
-- Mark Andrews, ISC 1 Seymour St., Dundas Valley, NSW 2117, Australia PHONE: +61 2 9871 4742 INTERNET: marka () isc org
Current thread:
- Re: Outgoing SMTP Servers, (continued)
- Re: Outgoing SMTP Servers Owen DeLong (Oct 25)
- Re: Outgoing SMTP Servers William Herrin (Oct 25)
- Re: Outgoing SMTP Servers Owen DeLong (Oct 25)
- Re: Outgoing SMTP Servers William Herrin (Oct 25)
- Re: Outgoing SMTP Servers Owen DeLong (Oct 25)
- Re: Outgoing SMTP Servers Mike Jones (Oct 25)
- Re: Outgoing SMTP Servers Owen DeLong (Oct 26)
- Re: Outgoing SMTP Servers Henry Yen (Oct 26)
- Re: Outgoing SMTP Servers Graham Beneke (Oct 25)
- Re: Outgoing SMTP Servers Ricky Beam (Oct 26)
- Re: Outgoing SMTP Servers Mark Andrews (Oct 26)
- Re: Outgoing SMTP Servers Leigh Porter (Oct 26)
- Re: Outgoing SMTP Servers Mark Foster (Oct 26)
- Re: Outgoing SMTP Servers Mark Andrews (Oct 26)
- Re: Outgoing SMTP Servers Bjørn Mork (Oct 27)
- Re: Outgoing SMTP Servers Jay Ashworth (Oct 26)
- Re: Outgoing SMTP Servers William Herrin (Oct 25)
- Re: Outgoing SMTP Servers Owen DeLong (Oct 25)
- RE: Outgoing SMTP Servers Matt McBride (Oct 25)
- Re: Outgoing SMTP Servers Ricky Beam (Oct 25)
- Re: Outgoing SMTP Servers Douglas Otis (Oct 25)