Re: interposition requirements

[Mark Little <mcl@arjuna.com>]

> >Not sure which Mark you mean, but I'll take a stab at it: first I don't
> >see that the participant and the sub-coordinator have to be different;
>
> Per f2f definitions a service and a participant are different interfaces
> (they may be the same entity - implemantation detail) , a service has a
> business function interface while a participant has a BTP interface.

That's fine. I was talking about the participant and the sub-coordinator,
not the service.

>
> >  if a participating web service wants to propagate the context to other,
> > back-end (for example) web services then as well as doing it's own work
> > when it's told to "prepare" it sends this message to those back-end
> > services, i.e., it acts like a sub-coordinator.
>
> It simply invokes a new service (depending on the context the
> sub-coordinator of service invoked may register with the root coordinator
> or with our sub-coordinator.)

Agreed.

> Whether the service invoked implements both a business service interface
> and a BTP interface depends on the implementation but as far as BTP
> concerened there is an interface to coordinate the transaction, it might
be
> the service it self - we don't know.

Yes, various people including myself have been saying this for a while.

Mark.

----------------------------------------------
Dr. Mark Little (mark@arjuna.com)
Transactions Architect, HP Arjuna Labs
Phone +44 191 2064538
Fax   +44 191 2064203