Blacklisting is very effective, but should be done carefully. Senderbase-like solutions proved to be _very_ effective, without much of false positives. What I do object, is uceprotect-like blacklists who automatically block huge ranges for a ridiculous amount of spam.
I do agree that blocking port 25, as tempting as it might sound for your average abuse desk personnel, is a stupid idea. -----Original Message----- From: Oleg Goldshmidt [mailto:p...@goldshmidt.org] Sent: Tuesday, April 07, 2009 9:02 PM To: Aviram Jenik Cc: Imri Zvik; linux-il@cs.huji.ac.il Subject: Re: Israeli ISP blocking outgoing SMTP Aviram Jenik <avi...@jenik.com> writes: > Noam didn't say blocking port 25 for everyone is a good thing or > that he likes it - just that this is what ISPs in Europe and the US > are doing that to fight spam. Not in my experience. That is, unless I grossly misunderstand the problem. In my mind, this means that the problem occurs when you configure a foreign server as your SMART_HOST while connected to the "octal 11" Israeli ISP. If this is _not_ the problem, please accept my apologies and ignore the rest. I have just returned from a trip to Europe. I sent emails, using my laptop, from two different Western European countries, from a hotel, from coffee shops, from occasional unidentified public Wi-Fi spot, etc. Presumably several different ISPs were involved, though I never bothered to make a list. Now, my laptop runs sendmail and has SMART_HOST configured to be my Israeli ISP's mail server. Thus, when I send an email from abroad, I am in a situation analogous to someone in Israel using a US server for outgoing SMTP traffic. Not a single email during my week-long trip (and I had to send quite a few) bounced or was lost. To me, this means that Western European ISPs do *not* prevent SMTP traffic reaching servers other than theirs. Last time I was in the US was last August, I had no problem there, either. In general, this does not make much sense. Imagine a typical Windows/Outlook user who has his "outgoing mail server" (SMART_HOST equivalent) configured to something (by his company's IT people, he himself does not know what an "outgoing mail server" is, etc.). Imagine this person on a trip somewhere - he does not change his configuration, but he doesn't normally have any problems sending email. If the "octal 11" Israeli ISP does it it is *not* following any common practice. Oh, and I agree it is stupid, as is blacklisting. -- Oleg Goldshmidt | p...@goldshmidt.org _______________________________________________ Linux-il mailing list Linux-il@cs.huji.ac.il http://mailman.cs.huji.ac.il/mailman/listinfo/linux-il
