Re: is SMTP a candidate for OPES ?

On Wed, 7 Jul 2004, Graham Klyne wrote:

> At 14:01 06/07/04 -0600, Alex Rousskov wrote:
> >Overall, there is nothing special about SMTP here, IMO: some OPES
> >adaptations require the whole message, some do not. Sometimes OPES
> >processing overheads delay the entire message; sometimes they delay a
> >portion of the message.
> >
> >Why is SMTP special at this level of thinking?
> ...
> In practice, I think this means that most real-world MTAs do store
> messages in a non-volatile message store, where they might arguably
> (I won't say "reasonably") be regarded as not in-transit.

Agreed, but the question remains: Why is SMTP a special case as far as
OPES architecture is concerned? What difference does permanent or
non-volatile storage make?

I can still apply the same kinds of adaptations before or after the
message is permanently or temporary stored, right? I understand that
SMTP is store-and-forward, but I do not understand why this creates
problems for OPES architecture. OPES is simply a polite way to do
man-in-the-middle adaptations. As long as the application protocol
allows for intermediaries (of any sort), OPES should be applicable.

Alex.