On Wed, 12 Mar 2003, Markus Hofmann wrote:
While probably separate from the callout protocol design, we also
need to discuss possible impact on the application message protocol,
for example for an "OPES bypass" mechanism. This refers to the
requirement that a user must be able to signal an OPES processor
that (s)he wants to bypass any OPES service (one of the IAB
requirements) - as briefly discussed some time earlier, using
(user-defined?) HTTP headers might be an option.... So we also need
to consider possible impact/extensions on the application message
protocol. Anyone some thoughts on this one?
You are right that this is pretty much unrelated to the callout
protocol: calls should no go out if OPES is being bypassed. The only
related aspect is that the callout protocol may have to pass user
bypass instructions/preferences _if_ we want to support selective
bypass (e.g., "bypass only this OPES/service"). I am not sure we need
that kind of selectivity at this point.
For each supported application protocol, we would need to define ways
to pass OPES preferences and tracing information. It should be fairly
easy for any application protocol that supports extensions (e.g., HTTP
and SMTP).
The first thing to decide is probably OPES identification/addressing
system that will be shared by both tracing and bypass OPES features.
What do we want to identify and/or address?
- just OPES processors
- OPES processors and callout servers
- OPES processors, callout servers, and services
- other?
Alex.