Paul Howarth wrote:
You got at least one reply (from me!):
<http://archives.listbox.com/spf-discuss(_at_)v2(_dot_)listbox(_dot_)com/200409/0589.html>
Paul, you did reply. Sorry I forgot to recognize that.
If your speculation is true, that the invention, at least the part having to do
with domain spoofing as opposed to the part having to do with IP spoofing,
applies only to MUA's and not to MTA's, then that would leave the field open
for SPF Classic and a lot of the other proposals that operate at the MTA level.
I have to say, that isn't the way I read it. But I still say the thing needs a
careful re-read. I am not at all convinced it says what many have assumed it
does. I am not at all convinved it really covers the PRA algorithm. It is a
complex application with multiple inventors. It is very possible nobody,
including the patent lawyers who wrote it, really understands what it says and
doesn't say. Harry Katz, one of the inventor's, has been asserting it doesn't
cover SPF Classic, though others think it does. Harry is certainly closer to
the origin of the thing than most of the rest of us, but even he is only one of
several inventors listed. I think, the devil is in the details, and the only
way to understand this thing is to dissect it like you would do an uncommented
program you were trying to figure out. Assign values to all the variables and
constants. Work out the flow. Figure out the results. I have a suspicion
that a careful analysis may well be somewhat surprising, even to Harry.
Mark Holm