from the because-individuals-should-not-have-them dept.
kmself writes "As first reported at linux-elitists by Aaron Sherman, and with a demonstration of the denial at zIWETHEY, AOL has begun blocking mailservers identified with residential DSL lines as an anti-spam measure, apparently heedless of the huge collateral damage this move imposes (and guess who can't send mail to Mom...). This action was unannounced, and has received virtually no coverage, spare an oblique mention at News.com. It also violates SMTP RFCs, as Aaron points out, not to mention the 'good neighbor' conventions of Internet communications. Mail to AOL's postmaster is also bounced -- this is RFC-ignorant.
I strongly recommend that as a compensatory measure, non-AOL MTAs be configured to deny all incoming mail from AOL's domain."
We warn the reader in advance that the proof presented here depends on a
clever but highly unmotivated trick.
-- Howard Anton, "Elementary Linear Algebra"