As a result of a recent post by Harry Katz, I've come to the
conclusion that the term 'Purported Responsible Address' may be a
mistake, and perhaps should be modified.
In the case of a Sender ID checker, the term makes sense. The
identity is only purported; we don't know yet if the message is
forged.
But we need a name for this concept that is applicable in other
contexts, too, including those where the implications of the word
'purported' are inappropriate, since the senders identity is known by
other means. (eg SASL)
Harry's objection to using PRA= instead of SUBMITTER= in the MAIL FROM
command is, as I understand it, that at this point the address isn't
purported, it's known.
I therefore suggest that the term Primary Responsible Address would be
more appropriate.
-roy