Slashdot Mirror

← Back to Stories (view on slashdot.org)

Comcast Gets Tough on Spam

Posted by michael on from the about-time dept.

WeakGeek writes "The Washington Post is reporting that Comcast, the nation's largest broadband ISP, has started blocking port 25 to reduce Spam. Jeanne Russo said Comcast is not blocking port 25 for all its users because it does not want to remove the option for legitimate customers who process their own e-mail. So the company is monitoring traffic and picking out machines that look suspicious. By blocking port 25, they say they cut Spam by 20% last week." ZDnet has another article, with a nice statistic: Comcast generates 800 million email messages/day, but only about 100 million of those are sent through Comcast's SMTP servers.

3 of 405 comments (clear)

  1. Why not work with the blacklists? by Anonymous Coward · · Score: 5, Insightful

    If they detect port 25 traffic over a certain threshold, do a quick dns blocklist check. If they're blacklisted, stop traffic on port 25 for that customer and contact them to let them know their machine may be infected.

  2. As a Comcast User... by rbabb · · Score: 5, Insightful

    ... This is starting to worry me a little. I have been happily running my own mail server for over a year now. The reason being is that I want the ability to host all my own solutions and at the same time use the bandwidth i'm already paying for.

    With wonderful dynamic DNS services like no-ip.org I am able to do this on any dynamic IP and I have no reason to worry about needing one of those pesky static IP addresses.

    Hopefully if something were to happen where I'd start getting blocked I could just use my connections at work and contact their e-mail admins directly to resolve the issue. However this slash and burn tactic is just the wrong way to go about fighting spam. Hence one of the reasons I left Earthlink/Mindspring, who block e-mail from ALL Dynamic IP addresses and also block outbound port 25 on their networks.

  3. Thanks to Spamhaus, Spamcop, Njabl RBLs by mabu · · Score: 5, Insightful

    And do you think Comcast finally took this step because they decided to stop their spamming users?

    Hell no!

    The only reason they got off their asses is because admins started wholesale blacklisting of their IP space and their customers started complaining.

    Blacklisting WORKS! It's the only way to force these ISPs to be responsible.

    If you're running content-based filtering, you're part of the problem. If you refuse SMTP traffic from confirmed spam sites, you are part of the solution.