Re: [ebxml-bp] FW: Differences between an operation and a BT

[Kenji Nagahashi <nagahashi@fla.fujitsu.com>]

Anders,

If I understood correctly, JJ is saying that particular WS operation 
cannot be reused by two or more different roles.
Assume there are two roles and WSDL operation defined for each:

Role A
	operation X

Role B
	operation Y

You cannot say "Party B invokes operation Y on party A" (even if X and Y 
are logically the same) since WSDL operations are inherently bound to 
particular role.
In contrast, with BT, you can say either "Role A initiates BT X" or 
"Role B initiates BT X".

JJ's statement "BT has no direction" might be too short :-)
BT itself does has direction, but it can be bound to any direction 
within outer collaboration. WSDL doesn't allow this.

Regards
Kenji


>>> Directed (A->B)                    No direction specified
>>> (BTA
>>>
>>> A BT is directed since it is asymetrical with and an Initiator and a 
>>> Responder role.   
>>
>> This statement is wrong. The roles are abstract. It is only when used 
>> in a BTA when you know the direction.  
>>
> <awt>
> yes, the roles are abstract. Its only when you start/enact/initiated the 
> BPSS when thay become concrete or real. But still a BT is asymetrical 
> with an abstract direction. When fitted into a BPSS using a proxy BTA 
> construct the abstract roles becomes bound to higher level roles through 
> the performs element in BTA. THis process is recursive all the way to 
> the top. i.e BPSS.
> <awt>