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Proposed wording for my action on "domain"

From: Maryann Hondo <mhondo@us.ibm.com>
Date: Wed, 2 Aug 2006 11:12:59 -0400
To: <public-ws-policy-eds@w3.org>
Message-ID: <OF10AB27FD.E4258222-ON872571BC.006C2B3B-852571BE.005394EE@us.ibm.com>
As per my actions:  http://www.w3.org/2006/07/27-ws-policy-minutes.html: 
<scribe> ACTION: editors to clear up 3.4 paragraphs about domain and also 
define domain expression [recorded in 
http://www.w3.org/2006/07/13-ws-policy-minutes.html#action15]

 Although the Action Items refers to text in section 3.4 there is no 
specific reference to "domain" in this section. 
Here is the list of my suggested changes for "domain" ( in red is my 
proposals, in black is the current text, and bold blue is the current use 
of "domain") 

Maryann

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CURRENT/Proposed changes: 

Domain - The original etymological implication of the word domain carries 
the idea of "something ruled". In Information Technology it commonly 
refers to a machine or a host on the Internet.( 
http://en.wikipedia.org/wiki/Domain) 

A "WS-Policy Domain" is a logical grouping  of assertions that a 
particular community has agreed to define (in conformance with the 
WS-Policy specifications) to facilitate the interoperability of web 
services within that community of interest.

A "WS-Policy domain expression" is an XML representation of a capability 
or a constraint within the context of a WS-Policy domain or community of 
interest.

1.1 Goals
The goal of Web Services Policy 1.5 - Framework is to provide the 
mechanisms needed to enable Web services applications to specify policy 
information. Specifically, this specification defines the following:
An XML Infoset called a policy expression that contains domain-specific, 
Web Service policy information.
A core set of constructs to indicate how choices and/or combinations of 
domain-specific policy assertions apply in a Web services environment.
....
3.1 Policy Assertion
A policy assertion identifies a behavior that is a requirement (or 
capability) of a policy subject. Assertions indicate WS-Policy domain
-specific (e.g., security, transactions) semantics and are expected to be 
defined in separate, WS-Policy domain-specific specifications [i.e. 
WS-SecurityPolicy, WS-ReliableMessagingPolicy] .Assertions are strongly 
typed by the domain authors that define them. The policy assertion type is 
identified only by the XML Infoset [namespace name] and [local name] 
properties (that is, the qualified name or QName) of the root Element 
Information Item representing the assertion. Assertions of a given type 
MUST be consistently interpreted independent of their policy subjects.
WS-Policy Domain authors MAY define that an assertion contains a policy 
expression as one of its [children]. Policy expression nesting is used by 
WS-Policy domain authors to further qualify one or more specific aspects 
of the original assertion. For example, security domain authors may define
d an WS-Policy assertion describing a set of security algorithms to 
qualify the specific behavior of a security binding assertion. 
The XML Infoset of an assertion MAY contain a non-empty [attributes] 
property and/or a non-empty [children] property. Such content MAY be used 
to parameterize the behavior indicated by the assertion. For example, an 
assertion identifying support for a specific reliable messaging mechanism 
might include an attribute information item to indicate how long an 
endpoint will wait before sending an acknowledgement. 
WS-Policy Domain authors should be cognizant of the processing 
requirements when defining complex assertions containing additional 
assertion content or nested policy expressions. Specifically, WS-Policy 
domain authors are encouraged to consider when the identity of the root 
Element Information Item alone is enough to convey the 

4.4 Policy Intersection
Policy intersection is useful when two or more parties express policy and 
want to limit the policy alternatives to those that are mutually 
compatible. For example, when a requester and a provider express 
requirements on a message exchange, intersection identifies compatible 
policy alternatives (if any) included in both requester and provider 
policies. Intersection is a commutative, associative function that takes 
two policies and returns a policy.
...
Because the set of behaviors indicated by a policy alternative depends on 
the domain-specific semantics of the collected assertions, determining 
whether two policy alternatives are compatible generally involves 
WS-Policy domain-specific processing. As a first approximation, an 
algorithm is defined herein that approximates compatibility in a WS-Policy 
domain-independent manner; specifically, for two policy alternatives to be 
compatible, they must at least have the same vocabulary (see Section 3.2 
Policy Alternative).
...
Assertion parameters are not part of the compatibility determination 
defined herein but may be part of other, domain-specific compatibility 
processing. 
...
As this example illustrates, compatibility between two policy assertions 
is based on assertion type and delegates parameter processing to domain
-specific processing.
...
Note that there are > 1 assertions of the type sp:SignedParts ; when the 
behavior associated with sp:SignedParts is invoked, the contents of both 
assertions are used to indicate the correct behavior. Whether these two 
assertions are compatible depends on the domain-specific semantics of the 
sp:SignedParts assertion. To leverage intersection, assertion authors are 
encouraged to factor assertions such that two assertions of the same 
assertion type are always (or at least typically) compatible.
Received on Wednesday, 2 August 2006 15:13:16 GMT

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