william(at)elan.net wrote:
On Fri, 8 Jul 2005, wayne wrote:
In <1120824561(_dot_)19467(_dot_)473(_dot_)camel(_at_)hades(_dot_)cambridge(_dot_)redhat(_dot_)com> David
Woodhouse <dwmw2(_at_)infradead(_dot_)org> writes:
But nobody volunteered any reasons why, in the _absence_ of SPF (which
we know has technical problems with forwarding) there is any other
reason to consider it to be a bad thing. I'd heard nobody say that
forwarding was wrong, or 'forgery', before SPF was invented. What,
_other_ than the technical problems of SPF, has changed?
I think, if you dig around in the archive, you will quickly find
people who have said that forwarding w/o rewriting is wrong
I disagree. The SMTP transmission is multi-stage and original sender is
correct source of the transmission. Inability to use this information to
authenticate sender based on its ip address of current stage SMTP client
does not necessarily means that data is wrong and should be replaced.
P.S. When telephone call is made and is forwarded somewhere else, what
number do you think is going to show up and who are you talking to?
consider A calls B. But B wants to receive the message at C.
Direct forwarding is not the same (your analogy above is more like
instant messaging). A better email compatible analogy is a message
service, where the message service takes the original message from A
destined for B. Then they call the new (forwarded) C destination. And
yes they do say "I have a message for you from A"
But the phone call goes like this:
This is the message service at B calling, I have a message from A for C.
Note that "This is the message service at B calling" is the RFC2821
identity.
Note that "I have a message from A" is the RFC2822 identity.
Terry
--
Terry Fielder
terry(_at_)greatgulfhomes(_dot_)com
Associate Director Software Development and Deployment
Great Gulf Homes / Ashton Woods Homes
Fax: (416) 441-9085