nanog mailing list archives
Re: Spam filtering bcps [was Re: Open Letter to D-Link about their NTP vandalism]
From: Henry Yen <henry () AegisInfoSys com>
Date: Wed, 12 Apr 2006 15:38:53 -0400
On Wed, Apr 12, 2006 at 12:03:51PM -0400, Joe Maimon wrote:
Matthew Black wrote:there's no bandwidth savings from silently dropping the message versus providing a 550 rejection. In the best of all worlds, it would be nice to give feedback. No system is perfect and a false-positive rate of less than one in a million "220" accepted messages seems pretty small.Let me ask you this simple question: If you know at close of DATA whether you are going to actually perform final delivery, what does it cost you to follow standards and issue a 550 instead of a 220 and discard it? If you use a 550, a real live person sending an email that somehow gets FP will actually benefit.
In today's world, at least with the spamtorrent I see at my clients, that's just untrue. If your filtering is set up well, and you mark an e-mail as SPAM, it almost certainly is (yes, I'll certainly concede FP's exist, but again, it almost certainly doesn't matter that much in that teensy number of occurrences); and 99-plus-percent of spam is emitted from spambots who don't give a $expletive about return status one way or another. If you're worrying about "no-status" in the context of FP's, then your filtering isn't set up well, which really means you've got larger problems.
I am with Suresh on this, just like in the past threads. Search the archive.
Though not contradicting what I just wrote, so am I. However, header-forged and multi-chained spam from firehose-like spambots don't play by any of our rules; all they do is blast away in a largely one-way transaction (guess which direction!). A 550 now-a-days has nowhere to "go" (and those "commercial" akak "legit") spamhouses don't wash their lists even on 550's. -- Henry Yen Aegis Information Systems, Inc. Senior Systems Programmer Hicksville, New York
Current thread:
- Spam filtering bcps [was Re: Open Letter to D-Link about their NTP vandalism] Suresh Ramasubramanian (Apr 11)
- Re: Spam filtering bcps [was Re: Open Letter to D-Link about their NTP vandalism] Tony Finch (Apr 12)
- Re: Spam filtering bcps [was Re: Open Letter to D-Link about their NTP vandalism] Matthew Sullivan (Apr 12)
- Re: Spam filtering bcps [was Re: Open Letter to D-Link about their NTP vandalism] Joe Maimon (Apr 12)
- Re: Spam filtering bcps [was Re: Open Letter to D-Link about their NTP vandalism] Matthew Black (Apr 12)
- Re: Spam filtering bcps [was Re: Open Letter to D-Link about their NTP vandalism] Suresh Ramasubramanian (Apr 12)
- Re: Spam filtering bcps [was Re: Open Letter to D-Link about their NTP vandalism] Matthew Black (Apr 12)
- Re: Spam filtering bcps [was Re: Open Letter to D-Link about their NTP vandalism] Suresh Ramasubramanian (Apr 12)
- Re: Spam filtering bcps [was Re: Open Letter to D-Link about their NTP vandalism] Matthew Black (Apr 12)
- Re: Spam filtering bcps [was Re: Open Letter to D-Link about their NTP vandalism] Joe Maimon (Apr 12)
- Re: Spam filtering bcps [was Re: Open Letter to D-Link about their NTP vandalism] Henry Yen (Apr 12)
- Re: Spam filtering bcps [was Re: Open Letter to D-Link about their NTP vandalism] Joe Maimon (Apr 12)
- Re: Spam filtering bcps [was Re: Open Letter to D-Link about their NTP vandalism] Tony Finch (Apr 12)
- Re: Spam filtering bcps [was Re: Open Letter to D-Link about their NTP vandalism] Steve Thomas (Apr 12)
- Re: Spam filtering bcps [was Re: Open Letter to D-Link about their NTP vandalism] Valdis . Kletnieks (Apr 12)
- Re: Spam filtering bcps [was Re: Open Letter to D-Link about their NTP vandalism] Matthew Black (Apr 12)
- Re: Spam filtering bcps [was Re: Open Letter to D-Link about their NTP vandalism] Steve Thomas (Apr 12)
- Re: Spam filtering bcps Bryan Bradsby (Apr 12)
- Re: Spam filtering bcps Valdis . Kletnieks (Apr 12)
- Re: Spam filtering bcps Andy Smith (Apr 13)
- Re: Spam filtering bcps Matthew Black (Apr 12)
- Re: Spam filtering bcps Matthew Sullivan (Apr 12)