I'm looking over your MTX site and like SPF I don't understand how it
stops spam. Thanks for at least addressing in part the email forwarding
issue.
In order to be a white list you have to do something spammers can't do.
I don't see what prevents spammers from creating good MTX records like
they do with SPF and whitelisting themselves. Since your idea also
requires blacklists to counter this effect then I'm still not sure what
this adds. As you know people register new domain names just to avoid
being on any list so your idea would seem to be a white list for those
who exploit that.
As to penalizing those who don't participate, I already have enough
headaches with SPF and others who want to inflict their personal
standards on the whole of the email community. SPF. which has left me
with a bad attitude, does nothing for me to catch spam or pass ham. But
it does result in good email that I forward being blocked.
I'm always looking for innovative ideas that actually work. I don't want
to discourage you. But the "actually works" part is very important. I
have had a lot of ideas that I got really excited about and after I
implemented them I found out that the idea wasn't quite as good as I
thought it would be.
As to whitelisting - there's actually a far easier solution that I use.
I do RDNS to get the host name. Then I forward confirm it to verify that
it is valid. Spammers can't spoof that. Then I look it up in my host
name white list of hosts who send nothing but good email. This actually
works extremely well. But like everyone I'm always looking for more
ideas especially for white rules because in y bustness one good email
bounced is words that 100 spams not bounced.
