Question regarding WS-Business Process

[Dominik <dominik.heller@gmx.net>]

Hello there,
I am reading trough the WS-Business Process specification right now and 
I am wondering if I am understanding everything correctly. So at first 
sight a Business Process seems to be structured like a normal 
transaction protocol with an atomic outcome. It has a root coordinator 
and some participants which are named tasks. These tasks can be within 
different domains whereas every domain needs a businessTaskCoordinator 
to manage the tasks in some way. So the root coordinator only knows the 
coordinators of the different domains which are his participants and his 
own tasks which are also participants. for terminating the business 
process every coordinator of a domain can register a 
terminatorParticipant which will be informed if the root coordinator is 
ready to be completed. So now my first question, how does the root 
coordinator will be informed to complete the business process? I can't 
find any messages send from the terminatorParticipant to the root 
coordinator with instructions to complete, as far as I can see it they 
only will get informed, right?

OK so although every domain can be implemented with whatever transaction 
specification like for example BTP, but the businessTaskCoordinator 
still has to be a Web Service in order to be enlisted as a participant 
with the root coordinator, right? So my final question, a root 
coordinator only knows the businessTaskCoordinator of a domain and never 
the sub-tasks of a domain, right?

thanks so much in advance for your help

Dominik Heller