Re: Does the selected Policy alternative apply in both directions?

On Sep 1, 2006, at 12:40 PM, Ashok Malhotra wrote:
> Hi Dan:
> You said
>> The requester's policy (may be implicit or explicit)
>> determines how the requester picks which policy alternative to use.
>
> Can you spell out that in a bit more detail.
>
> Also, I think you are saying that the provider and requesters policies
> can be different.  Is this correct?

I'd like to try a reading of Daniel's bit, as I think it's close to  
my understanding and would like to test that :)

I am a potential requester. I have policies to which I must adhere  
set by my owner.

I want to use a service. It has policies that describe what one must  
do in order to use the service.

So, I retrieve the service's policy (e.g., via a WSDL) and look at it  
to see if what the service requires of me is something I'm permitted  
to do. That is, I see if there is an alternative of the service's  
policy that is compatible with an alternative of my policy.

If there is, I select that alternative, and send a message that  
conforms to both alternatives. The service just needs to verify that  
the received message conforms to some alternative of its policy.

(Of course, if you could name which alternative the requestor is  
using, it would save a bit on the service end, but I suspect that's  
pretty negligable.)

Cheers,
Bijan.

Received on Friday, 1 September 2006 12:18:15 UTC