Re: Pi-Calculus Model question.

Assaf, maybe I missed something but the examples you walked us through
can be coded in pi-c but also in CCS which is a subset of pi-c. I did
not see any channel passing between processes. Is this intentional from
you to simplify the examples?

I think the challenge for the WS-CHOR WG will be how to pick the right
formal model that captures the use-cases we want to support, where a
subset of pi-c MAY be good enough. For example, if we don't care of
passing channels then we can use CCS instead of pi-c. If we want to pass
channels between processes (for a callback for example) then we have
different options: use full pi-c, use symmetric-pi-c (only fresh
channels can be passed around), use linear channels (a channel can be
used only once for a send and only once for a receive), etc. For any of
this to happen there has to be a type system for channels which
restricts the usage of channels. Also, channels have to become first
class citizens in WS. WS-Addressing maybe something to look at and see
how we can use it.

Another important criteria, which may affect our decision for picking
the right formal model is how a system that executes the WS-CHOR
language (which will based on the formal model) will be implementated.
Lucian for example, among others has developed explicit-fusions-calculus
where its machine can effiecienlty implement synchronous rendezvous in a
distributed environment. Asynchronous-pi is another example of that.

Received on Monday, 14 April 2003 15:46:50 UTC