Alex Rousskov wrote:
- It looks like Markus (and others?) want callout servers and
even services be traceable and, hence, exposed to the ends to a
certain degree.
Amongst others, this came from IAB considerations 3.1 and 3.2 in
RFC3238, which require that the ends can detect OPES actions. In
particular, a user/end must be able to respond to OPES actions that
"are deemed inappropriate" by herself - as such, all OPES actions need
to be exposed to the end/user.
We will need to get some consensus here. What
is exposed to ends?
I would assume that all services that have been executed on a message
are identified and exposed - or that a reference is given at which the
end-user can query which services have been executed.
> If something is exposed, does it communicate
with ends? If it does, what "band" is used?
Could be a combination of in-band and out-of band. For example,
in-band annotations could be used to expose a reference to the end
user (e.g. a URL), at which the end-user can retrieve additional
information about the services (and servers?) that have been executed
on the message using a separate (out-of-band) mechanism.
Might remind of email: Email uses in-band annotations (i.e. the
Received: headers) to let the user know which mail servers have been
involved in handling an email. The user can then use out-of-band
mechanisms to contact the postmaster of any mail server for further
info...
-Markus