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North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical SMTP rate-limits [Was: Re: ingress SMTP]
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 - -- Simon Waters <[email protected]> wrote: >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. > Okay, I can understand why an ISP might want to apply SMTP rate-limits, but to clarify, I'm assuming you meant that ISPs (if they do block tcp/25 outbound to anything other than their own MTAs) need to watch for excessive SMTP utilization, which might indicate a spammer-client (?). ...as opposed to arbitrary SMTP rate-limits. Yes? - - ferg -----BEGIN PGP SIGNATURE----- Version: PGP Desktop 9.6.3 (Build 3017) wj8DBQFIwO90q1pz9mNUZTMRAneaAJwMgmIz99bPUYJ2HgUD6Zs1MOFXgQCgmsPY eUtV2bBKymWfxNwNOgWfp5w= =bdk+ -----END PGP SIGNATURE----- -- "Fergie", a.k.a. Paul Ferguson Engineering Architecture for the Internet fergdawg(at)netzero.net ferg's tech blog: http://fergdawg.blogspot.com/
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