On Mon, Apr 14, 2014 at 09:03:44AM -0400, Patrick Hemmer wrote: > While I strongly disagree, I can respect your reasoning. But perhaps > there are solutions other than restricting non-subscribers. I can think > of these few without much thought: > 1) add grey listing (http://en.wikipedia.org/wiki/Greylisting).
We already have some greylisting which is why we have "only" a little bit of spam. > 2) add a header indicating whether the sender is subscribed to the > mailing list. Then anyone who wants to remain on the list can add a > filter to auto-delete mail when the sender isn't on the list. I don't > know the numbers, but I'd bet the valid non-subscriber mail is rare. Among 2000 participants, we have 700 permanent subscribers, which means that other ones unsubscribe after a few exchanges. Some people (including myself) also have multiple addresses and will post from work or home using a different one while they don't want to be subscribed multiple times. > 3) Add a spamhaus IP blacklist. While I doubt this would block any > legitimate mail, it is possible. So I expect this to be met with the > same resistance as only allowing subscribers. We're currently using one such crappy BLs, which was the reason people from gmail were recently denied posting. So we had to relax them. The problem with blacklists is that they're maintained by people who quickly get addicted to the great power they have by being able to decide who is allowed to send mail and who isn't allowed. It quickly turns a technical tool into a political one. I don't have a magic solution to this. The real point is that a mailing list always comes with some spam and any mailbox also comes with some spam anyway. So as long as the mailing list only adds a few percent of spam to the one you already have, I really think it's not worth blocking legitimate users to try to save this. Willy
