nanog mailing list archives
Re: ingress SMTP
From: Simon Waters <simonw () zynet net>
Date: Fri, 5 Sep 2008 09:21:17 +0100
On Friday 05 September 2008 00:33:54 Mark Foster wrote:
*rest snipped* Is the above described limitation a common occurrance in the world-at-large?
If the ISP blocks port 25, then the ISP is taking responsibility for delivering all email sent by a user, and they have to start applying rate limits. Otherwise if they send all email from their users, all they've done is take the spam, and mix it in with the legitimate email, making spam filtering harder. Locally one of the big ISP insists you register all sender addresses with them, so all the spam from them has legitimate sender credentials. The problem is that by blocking port 25, you are basically then switching users to arbitrary per ISP rules for how to send email. This is probably good for ISPs (provides some sort of lock-in) but bad for their users. Whilst the antispam folk think it is a godsend because their block lists are smaller, it is relatively easy to block spewing IP addresses, and hard to filter when good and bad email is combined. Which is why they hate Google hiding the source IP address. This will continue until the real issue is addressed, which is the security of end user systems.
Current thread:
- Re: ingress SMTP, (continued)
- Re: ingress SMTP Mark Andrews (Sep 04)
- Re: ingress SMTP Alec Berry (Sep 04)
- Re: ingress SMTP matthew (Sep 03)
- RE: ingress SMTP Justin D. Scott (Sep 03)
- Re: ingress SMTP matthew (Sep 03)
- ingress SMTP Keith Medcalf (Sep 03)
- Re: ingress SMTP Mark Foster (Sep 03)
- Re: ingress SMTP Jeff Kinz (Sep 04)
- Re: ingress SMTP Mark Foster (Sep 04)
- Re: ingress SMTP Jeff Kinz (Sep 04)
- Re: ingress SMTP Simon Waters (Sep 05)
- Re: ingress SMTP Mikael Abrahamsson (Sep 05)
- Re: ingress SMTP Mark Foster (Sep 05)
- Re: ingress SMTP Robert E. Seastrom (Sep 10)
- Re: ingress SMTP Jeff Kinz (Sep 05)
- Re: ingress SMTP Mark Foster (Sep 03)
- Re: ingress SMTP Suresh Ramasubramanian (Sep 03)
- Re: ingress SMTP Ang Kah Yik (Sep 03)