In <42D7FD15(_dot_)9090207(_at_)de-korte(_dot_)org> Arjen de Korte
<spf+discuss(_at_)de-korte(_dot_)org> writes:
wayne schreef:
"exists:abc:spf.example.com"
Is this a parse error? Or a domain with a ":" in it?
Or an unknown mechanism "exists:abc"?
That is a domain with a colon in it. Mechanisms can not have colons.
That is an illegal domain name. According to RFC 1035, domain names can
not have colons.
No.
It is a perfectly legal domain name. See RFC1035, section 2.3.3. If
that isn't clear enough, see RFC2181, section 11.
This is a FAQ, we need to write it up somewhere.
The requirements for a "host name" is different than the requirements
for a "domain name". Host names can not contain things like colons,
underscores, or slashes, but domain names can. Host names are a
proper subset of domain names. All host names are domain names, but
not all domain names are host names.
Trust me on this one. I don't have time to dig up longer answers
right now, but this would be a good task for someone to write up a FAQ
entry on.
-wayne