RE: NEW ISSUE: Policy Compatibility Check must account for level of N esting of Policy Alternatives

RE "There is scope however for interpretation, that if an alternative
(at any nesting level) in one matches the alternative (at any nesting
level) in the other, the two policies can be considered compatible."

 

In Section 4.4, the requested distinction is called out at the policy
level:

 

-        'policy' vs. 'nested policy', and

-        'an alternative' vs. 'the alternative in the nested policy'

 

This distinction is consistently maintained throughout Section 4.4 which
seems to clarify any ambiguity raised by this e-mail.

 

PS: I'll update your entry in Bugzilla.

 

Regards,

 

Asir S Vedamuthu

Microsoft Corporation

________________________________

From: public-ws-policy-request@w3.org
[mailto:public-ws-policy-request@w3.org] On Behalf Of Prasad Yendluri
Sent: Wednesday, July 26, 2006 4:10 PM
To: public-ws-policy@w3.org
Subject: NEW ISSUE: Policy Compatibility Check must account for level of
N esting of Policy Alternatives

 

Title: Policy Compatibility Check must account for level of Nesting of
Policy Alternatives

 

Description: Section 4.4 of the WS-Policy 1.5 - Framework specification
states:

 

*         "Two policies
<http://dev.w3.org/cvsweb/~checkout~/2006/ws/policy/ws-policy-framework.
html?content-type=text/html;%20charset=utf-8#policy#policy>  are
compatible if an alternative in one is compatible with an alternative in
the other. If two policies are compatible, their intersection is the set
of the intersections between all pairs of compatible alternatives,
choosing one alternative from each policy. If two policies are not
compatible, their intersection has no policy alternatives."

 

However, per section 4.3.2 (Policy Assertion Nesting), a policy
Assertion may contain a nested Policy. 

 

The intent of the above text is to check compatibility of alternatives
at the top level of the subject policies only. There is scope however
for interpretation, that if an alternative (at any nesting level) in one
matches the alternative (at any nesting level) in the other, the two
policies can be considered compatible.

 

In addition section 2.3 terminology defines a policy to be "collection
of policy alternatives
<http://dev.w3.org/cvsweb/~checkout~/2006/ws/policy/ws-policy-framework.
html?content-type=text/html;%20charset=utf-8#policy_alternative#policy_a
lternative>  "only. 

No further constraints on the origin of alternatives in the collection.

 

Similarly section 3.3 (Policy) defines a policy to be: "a policy
<http://dev.w3.org/cvsweb/~checkout~/2006/ws/policy/ws-policy-framework.
html?content-type=text/html;%20charset=utf-8#policy#policy>  is a
potentially empty collection of policy alternatives
<http://dev.w3.org/cvsweb/~checkout~/2006/ws/policy/ws-policy-framework.
html?content-type=text/html;%20charset=utf-8#policy_alternative#policy_a
lternative> "

 

Justification:

There is scope for interpretation that needs to be eliminated. 

 

Target: WS-Policy 1.5 - Framework

 

Proposal - 

 

1. Tighten up the definition of policy to be specific about the (nesting
level / origin of) "collection" of alternatives it groups. 

     I am Opening a separate new issue for it. If that is properly
resolved, this issue is automatically resolved.

2.  Rephrase the policy compatibility statement to say "Two policies
<http://dev.w3.org/cvsweb/~checkout~/2006/ws/policy/ws-policy-framework.
html?content-type=text/html;%20charset=utf-8#policy#policy>  are
compatible if a top level alternative in one is compatible with a top
level alternative in the other."

 

Regards,

Prasad Yendluri