AOL blocking DynDNS Mailhop-Outbound

[Tom Metro]

Robert Krawitz wrote:
> Perhaps, but it's possible that passage through a downstream trusted
> MTA "sanitizes" them (i. e. that AOL trusts Comcast's servers if it
> comes from them).

But sanitizing is exactly what Rich is buying with DynDNS's Mailhop
service. The other half of your point is "if it comes from them."
Presumably AOL is using SPF to determine that the client (relay's) IP is
a permitted sender for Rich's domain. I didn't ask, but I assume Rich
has set up an SPF record to do that.

Maybe the absence of SPF records for most domains relayed through
DynDNS's Mailhop makes their relay appear like an open relay from AOL's
perspective?

 -Tom

-- 
Tom Metro
Venture Logic, Newton, MA, USA
"Enterprise solutions through open source."
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