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Re: Fun new policy at AOL
From: Matthew Crocker <matthew () crocker com>
Date: Thu, 28 Aug 2003 10:18:45 -0400

In article <20030828111600.C282.RICHARD () mandarin com>, Richard Cox
<Richard () mandarin com> writes
We can thank the usual suspects - Cogent, Qwest, AT&T, Comcast - and in
Europe: BT, NTL and possibly the world-abuse-leader, Deutsche Telekom
(who run dtag.de and t-dialin.net) for this being the situation.

Here's another tale of undeliverable email. It seems that [at least] one
of those organisations you mention assigns IP addresses for its ADSL
customers from the same blocks as dial-up. Which means that
organisations using MAPS-DUL reject email from teleworkers (or indeed
people running businesses with an ADSL connection) who run their own
SMTP servers.
Roland Perry

Shouldn't customers that purchase IP services from an ISP use the ISPs mail server as a smart host for outbound mail? We block outbound port 25 connections on our dialup and DSL pool. We ask our customers that have their own mail servers to configure them to forward through our mail servers. We get SPAM/abuse notifications that way and can kick the customer off the network. We also block inbound port 25 connections unless they are coming from our mail server and require the customer setup their MX record to forward through our mail server. We virus scan all mail coming and going that way. We protect our customers from the network and our network from our customers. We are currently blocking over 3k Sobigs/hour on our mail servers. I would rather have that then all my bandwidth eaten up by Sobig on all of my dialup/DSL connections.

SMTP & DNS should be run through the servers provided by the ISP for the exact purpose. There is no valid reason for a dialup customer to go direct to root-servers.net and there is no reason why a dialup user should be sending mail directly to AOL, or any mail server for that matter (besides their host ISP)


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