On 23 Mar 2005 at 14:55, Marilyn Davis wrote about
"Re: [exim] Heads up?":
|...
| > FWIW, if a C/R system *only* sent challenges to envelope senders that
| > have been verified by one of the schemes to prevent envelope-sender
| > spoofing (SPF, DK, SES, etc), *then* it would not have the collateral
| > spam problem. But it wouldn't be very usefull...
|
| Hmmmmm. It wouldn't be very useful because????
1. Because you'd not be challenging the bulk of your spam, you'd
mainly be (uselessly) challenging legitimate mail.
2. Because it depends on said scheme(s) being widely adopted.
| Because by then, you
| should just accept the mail and be confident that it is ham? No,
| spammers can register themselves at SPF too.
*If* a viable sender verification scheme gets widely adopted, then
you'd be able to use name-based DNSBLs to reject mail from the
spammer's (verified) sender domains.
There would still be no good reason to annoy your legitimate senders,
losing some legitimate mail in the process.
- Fred
