A BPEL definition
Wednesday, March 31, 2010
2:23 PM
A BPEL process
<process name='foo'> 
<!-- BPEL "activities" --> 
</process> 
An activity can be
Receiving a message. 
Sending a message. 
Querying a service. 
A sequence of activities. 
A set of parallel activities. 
For, while, do… until loops. 
If-else constructions. 
Pick: switch on first message received.
Aside: BPEL is not based upon lambda-calculus, but upon an alterative pi-calculus. 