> -----Original Message----- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On > Behalf Of Julia Thompson
> How does this IP-based open relay blocking work? > > I ask because awhile back, I was in the situation of all my outgoing mail > going through a server that was known as an open relay; I got mail bounced > back to me for that reason (fortunately I had another address for > the party > I was trying to correspond with, or the conversation would have > died and he > wouldn't have known why, and might have been upset with *me*), and I'm > wondering if anyone is currently in that situation, and if so, > depending on > how the blocking worked, would end up being for all intents and purposes > censorship of that person, even if that were not the *real* intent. A little background for those who may be confused. An open relay is a mail server (what your mail client *sends* mail through) that will let you send mail to any domain. In the good old days of the Internet, before spam, people didn't generally mind if you used their mail server for your outgoing mail. There was no need to set up your own server for many people, because you could usually find a machine that would accept your mail. But open relays are a spammer's dream, because they allow anybody to send mail to anybody. Spammers have two choices -- find an ISP that will allow them to operate legitimately, or find an open relay that they can use. The former is getting harder and harder, as ISPs realize their liability if they don't catch this stuff fast. A few years back, Paul Vixie (who wrote BIND, as I recall), came up with an easy way to share the identities of open relays -- use the domain name system. This isn't the "real" DNS, it just uses the same software, since the the IP address of the open relay is what needs to get shared around. And DNS is great for sharing IP addresses. Thus, the real-time blackhole came into being. Now there are several such services, some free, some for pay (including Paul's original service and follow-ons, unless you're an individual). And there have been serious legal fights, to the point where it's necessary to fax in an agreement to use the original. Some market research companies sued Paul's company because they were blocked as known spammers, having send millions of unsolicited surveys by e-mail. By any liberal definition, that's spam. But Harris, etc., saw that this would make their traditional business very, very difficult, so they sued. All this is from memory, I may be screwing up a detail or two. The black-hole list operators tend to be very careful about making sure that a given server really is open or really is spamming before they block it. And they make it relatively easy to get off the list when you've fixed the problem (open relays are often accidental -- Sendmail is hideous to configure.) Otherwise, they'd really have some liability issues, as you might imagine. Now watch and enjoy as I tie this back to the list's topic -- David Brin. When I was a vp of Invisible Worlds, Paul was on our advisory board and hosted our servers. I had to drop off something at his offices in Redwood City and was more than a little intrigued to see a car sitting in the parking lot with the license plate, "Kithrup." Turns out that that's where kithrup.com lives, and there's a big fan of DB who works with Paul. Nick _______________________________________________ http://www.mccmedia.com/mailman/listinfo/brin-l