nanog mailing list archives
Re: ISP port blocking practice
From: Owen DeLong <owen () delong com>
Date: Sat, 4 Sep 2010 03:40:17 +0930
Sent from my iPad On Sep 3, 2010, at 10:10 PM, John Levine <johnl () iecc com> wrote:
Really? So, since so many ISPs are blocking port 25, there's lots less spam hitting our networks?It's been extremely effective in blocking spam sent by spambots on large ISPs. It's not a magic anti-spam bullet. (If you know one, please let us know.)
That simply hasn't been my experience. I still get lots of spam from booted hosts in large provider networks, and yes, that includes many that block 25. As near as I can tell, 25 blocking is not affecting spammers at all, just legitimate users. There was a time when it was effective, but the spammers have long since adapted. Now we are only breaking the Internet. We are no ,onger accomplishing anything ireful. It's pure momentum.
workaround. Since, like many of us, I use a lot of transient networks, having to reconfigure for each unique set of brokenness is actually wasting more of my time than the spam this brokenness was alleged to prevent.Is there some reason you aren't able to configure your computers to use tunnels or SUBMIT? They seem to work pretty well for other people.
Many of the transient networks I deal with block 22, 25, 465, and 587. They also often block protocols 41 and 43 or do not provide a public address, rendering those protocols unusable anyway. Yes, I am now running ssh and s,tp processes on ports 80 and 443 to get around this, but, that consumes an extra address for something that should be handled by a port number. Personally, i'd rather use port numbers for l4 uniqueness rather than IP Addresses. Owen
R's, John
Current thread:
- Re: ISP port blocking practice, (continued)
- Re: ISP port blocking practice Randy Bush (Sep 03)
- Re: ISP port blocking practice Nick Hilliard (Sep 03)
- Re: ISP port blocking practice Owen DeLong (Sep 03)
- Re: ISP port blocking practice Curtis Maurand (Sep 03)
- Re: ISP port blocking practice Dobbins, Roland (Sep 03)
- Re: ISP port blocking practice Kevin Oberman (Sep 04)
- Re: ISP port blocking practice Owen DeLong (Sep 03)
- Re: ISP port blocking practice Butch Evans (Sep 03)
- Re: ISP port blocking practice Owen DeLong (Sep 03)
- Re: ISP port blocking practice John Levine (Sep 03)
- Re: ISP port blocking practice Owen DeLong (Sep 03)
- Re: ISP port blocking practice John R. Levine (Sep 03)
- RE: ISP port blocking practice Paul Stewart (Sep 03)
- Re: ISP port blocking practice Doug Barton (Sep 03)
- Re: ISP port blocking practice Franck Martin (Sep 03)
- Re: ISP port blocking practice Owen DeLong (Sep 03)
- Re: ISP port blocking practice John R. Levine (Sep 03)
- Re: ISP port blocking practice Robert E. Seastrom (Sep 08)
- RE: ISP port blocking practice Brian Johnson (Sep 12)
- Re: ISP port blocking practice Patrick W. Gilmore (Sep 03)
- Re: ISP port blocking practice Ricky Beam (Sep 03)