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RE: NEW ISSUE :Clarify usage of assertions with no behavioral requirements on the requeste

From: Asir Vedamuthu <asirveda@microsoft.com>
Date: Wed, 18 Oct 2006 08:55:33 -0700
Message-ID: <1E0F0378382054439F14D5450650478F0AC5244A@RED-MSG-42.redmond.corp.microsoft.com>
To: Sergey Beryozkin <sergey.beryozkin@iona.com>, <public-ws-policy@w3.org>

> it's important to ensure
> policy-aware clients which have no knowledge 
> of these assertions can proceed
> consuming the service advertsing this assertion.

I'd like to understand this case better.

Let's consider a slightly different example. Say provider X has an open privacy policy (X collects personal information and sells them). Provider X uses a policy assertion Y to advertise this behavior. Requestor Z doesn't understand assertion Y.

I can't think of a reason why requestor Z should interact with provider X.

> marking assertions like <oasis:Replicatable/> with
> wsp:optional is considered to be a wrong approach.

Agree.

Regards,
 
Asir S Vedamuthu
Microsoft Corporation




From: public-ws-policy-request@w3.org [mailto:public-ws-policy-request@w3.org] On Behalf Of Sergey Beryozkin
Sent: Wednesday, October 04, 2006 2:15 AM
To: public-ws-policy@w3.org
Subject: NEW ISSUE :Clarify usage of assertions with no behavioral requirements on the requeste

http://www.w3.org/Bugs/Public/show_bug.cgi?id=3789

Target : WS-Policy Framework and policy guidelines

Justification :

There's a class of policy assertions which have no behavioral requirements on the requester but can be still usefully processed by 
requesters which are aware
of what assertions mean.
For example : <oasis:Replicatable/>

An assertion like this one can be a useful source of information for requesters. Providers having expected properties like 
<oasis:Replicatable/> can be chosen/searched.
At the same time, given the fact assertions like <oasis:Replicatable/>
have no behavioral requirements on the provider it's important to ensure
policy-aware clients which have no knowledge of these assertions can proceed
consuming the service advertsing this assertion.

Currently the way to advertise such an assertion is to use a normal form with two policy alternatives(simple case), with only one 
alternative containing this assertion thus making it optional, or, in other words, giving a chance to requesters to ignore it.
Such normal form expression is equivalent to a compact form with the optional assertion marked with wsp:optional attribute with a 
value 'true'.

However, at the moment the primer recommends using wsp:optional when one needs to mark asssertions which identify optional 
capabilities/requirements with behavioral requirements on a requester should the requester wishes to use it.

Thus marking assertions like <oasis:Replicatable/> with wsp:optional is considered to be a wrong approach.

Proposal :

Clarify the text describing the optionality in the policy guidelines and in the Framework spec on how a policy author should use 
assertions like
<oasis:Replicatable/>.
It's important that assertions like these can be usefully interpreted by knowledgeble requesters and safely ignored by requesters 
unaware of them. 
Received on Wednesday, 18 October 2006 15:56:31 GMT

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