Re: Terminology - What is a process? Was: Internal processes and/or external choreographies (was RE: Ev ents and States ...

Jean-Jacques Dubray wrote,
> With respect to pi-c no matter how I stear at it I don't see an
> explicit choreography specification. All I see is the specification
> of the behavior of agents which are capable of communicating which
> each other. If you take the example: _xy.0 | x(u)._uv.0 | _xz.0, it
> expresses the behavior of each agent and the composition "point" but
> by no means the "choreography" is "visible" there. Furthermore,
> pi-calculus seem to be limited to request/response message exchange
> patterns (I'd be curious to know how one would model complex MEPs).

I think there might be some truth in this.

That said, there's work being done on extending pi with "session types" 
... roughly speaking these allow protocols to be encoded as the types 
of channels. It's possible that this might be useful approach to making 
choreographies visible in the way you want.

I think this paper,

  http://www.di.fc.ul.pt/~vv/papers/stipc.pdf

by Simon Gay, Vasco Vasconcelos and and Antonio Ravara might be helpful. 
Also this one,

  http://www.dcs.gla.ac.uk/~simon/publications/TR-2003-131.pdf

which uses POP3 as an example of a not completely trivial protocol which 
can be encoded in this way.

Cheers,


Miles

Received on Tuesday, 15 April 2003 18:27:29 UTC