..OO.. Wheeling thru - by Asir

Changes in WS-Policy Proposed Recommendation Drafts

A list of changes since the Candidate Recommendation drafts is at http://asir.selvasingh.com/blog/changes-in-ws-policy-pr.html.

WS-Policy is W3C Proposed Recommendation!

On July 6th, the W3C published the Web Services Policy specifications (Framework and Attachment) as Proposed Recommendations. Web Services Policy is a metadata language that extends the foundation on which to build interoperable Web services. There is a strong community of active members in the W3C WS-Policy Working Group. Ten companies participated in the interop testing during the W3C implementation gathering phase. Windows Communication Foundation enables features such as security, reliability, transaction and message optimization using the Web Services Policy language.

How Does an Application Retrieve Policies?

Just as other service metadata languages (say XML Schema and WSDL), Web Services Policy does not mandate any specific policy retrieval mechanism or specify a mechanism to indicate a (or a sequence of) retrieval mechanism (s).

Any combination of any retrieval mechanisms in any order may be used for referencing policy expressions. Choice of one or more retrieval mechanisms (or a sequence of retrieval mechanisms) is a prerogative of the application that references a policy expression. Example retrieval mechanisms are:

• Do nothing. A policy expression with the referenced IRI is already known to be available in a local cache or chip (embedded systems).
• Use the referenced IRI and retrieve an existing policy expression from the containing XML document: a policy element with an XML ID.
• Use the referenced IRI and retrieve a policy expression from some policy repository/registry (local or remote) or catalog. Policy tools may use any protocols (say Web Services Metadata Exchange) for such metadata retrieval. These protocols may require additional out of band information.
• Attempt to resolve the referenced IRI on the Web. This may resolve to a policy element or a resource that contains a policy element.

These illustrative examples are briefly described in the Web Services Policy Primer.

By not mandating any specific policy retrieval mechanism or specifying a mechanism to indicate a (or a sequence of) retrieval mechanism (s), the Web Services Policy Framework offers a level of abstraction from any underlying concrete application context. This way, a policy expression is usable in different environments.

Changes in WS-Policy Last Call Drafts

A list of substantive changes since the WS-Policy Member Submission is below:

Web Services Policy Framework

1. Defined WS-Policy 1.5 Framework and Attachment XML Namespace Name versioning policy (see 2.3 XML Namespaces).
2. Added support for the xml:id attribute (see 4.2 Policy Identification).
3. Added a conformance section – 6. Conformance.
4. Replaced URI with IRI.
5. Enhanced 5. Security Considerations (new content is from the Security Considerations Section in the Understanding WS-Policy MSDN white paper).
6. Clarified that an unrecognized element within a policy expression MUST be an assertion (see 2.2 Extensibility).
7. Clarified that policy assertion parameters are opaque to framework processing (see 4.3.2 Policy Assertion Nesting).
8. Added element extensibility (via {Any}) to the PolicyReference element (see 4.3.4 Policy References).
9. Added a new feature: 4.4 Ignorable Policy Assertions.
10. Defined an XML Media Type to describe Web Service Policy documents serialized as XML in Appendix A. The application/wspolicy+xml Media Type.

Web Services Policy Attachment

1. Defined WS-Policy 1.5 Framework and Attachment XML Namespace Name versioning policy (see 2.2 XML Namespaces).
2. Added a conformance section – 8. Conformance.
3. Replaced URI with IRI.
4. Added a new section - 5. WS-Policy Attachment for WSDL 2.0 - that describes a mechanism for associating policy expressions with Web service constructs in WSDL 2.0.
5. Added a new domain expression: 3.4.1 URI Domain Expression.

Check out WS-Policy Last Call Drafts

Today, the Web Services Policy Working Group published the Last Call drafts:

• http://www.w3.org/TR/2006/WD-ws-policy-20061117
• http://www.w3.org/TR/2006/WD-ws-policy-attach-20061117

Check them out! Later, I'll post a list of substantial changes in these drafts since WS-Policy Member Submission.

Check out Updated WS-MetadataExchange Specification

WS-MetadataExchange has been republished based on community feedback. Updates include the use of the WS-Transfer Get operation for the retrieval of metadata and the description of how to push metadata to consumers using WS-Addressing Endpoint References.

Link - http://schemas.xmlsoap.org/ws/2004/09/mex/

At Microsoft, I am a technical diplomat and responsible for standardizing and building industry momentum around WS-* metadata specifications such as WS-MetadataExchange and WS-Policy. For this publication, I had the pleasure of working with specification authors from BEA, IBM, CA, Microsoft, SAP, Sun and webMethods.

Check out 'Understanding Web Services Policy' Paper

This morning, Microsoft published the 'Understanding Web Services Policy' white paper, which I co-authored with Dan Roth.

URI - http://msdn.microsoft.com/ws/2006/07/understanding-ws-policy/

Understanding Web Services Policy is an introductory description of the Web Services Policy language. This document describes the policy language features using numerous examples. This document is:

• for product decision makers who need to know the features of the language and how policy automates Web service interactions,
• for policy expression authors who need to understand the syntax of the language and understand how to build consistent policy expressions,
• for policy implementers whose software modules read and write policy expressions and
• for policy assertion authors who need to know the features of the language and understand the requirements for describing policy assertions.

For this white paper, I had the pleasure of working with Paul Cotton, Colleen Evans, Kirill Gavrylyuk, Martin Gudgin, Ram Jeyaraman, Andrew Layman, Jonathan Marsh, Jeffrey Schlimmer, Daniel Roth,  Jorgen Thelin  and Kyle Young. Writing this paper was satisfying and a great learning experience.

Check it out!

Sun and Microsoft Showcase WS-* Interoperability

Interop on the following WS-* specifications:

Quality of Service -- WS-Reliable Messaging, WS-Coordination, WS-Transactions
Security -- WS-Security, WS-Trust, WS-Secure Conversation, WS-Security Policy
Metadata -- WSDL, XML Schema, WS-Policy, WS-Metadata Exchange
Messaging -- SOAP, WS-Addressing, Message Transmission Optimization Mechanism (MTOM)

Read more ...

Industry Demonstrates WS-Policy Interop

WS-Policy Interop Workshop was a resounding success!

Authors of the Web Services Policy specifications hosted a three day interop workshop from April 25th to 27th. This meeting was hosted by SAP at their Walldorf campus in Germany. The interop workshop was an open forum for Web Services Policy implementors to test round 3 security policy interop scenarios, run round 1 and 2 unit test cases and offer feedback.

There were 15 participants representing 7 compaines at the workshop: BEA Systems, IBM, Layer 7 Technologies, Microsoft, SAP, Sun and WSO2.

WS-Policy in the News

"Because of its importance to SOA and Web services, Kyle Young, program manager for connected systems at Microsoft, noted that WS-Policy has the support of vendors who are not authors, but are members of W3C." - SearchWebServices.com

"IBM, BEA, Others Submit SOA Web Services Proposal to W3C" - SOA Web Services News Desk

"While policy is important for any aspect of software or IT infrastructure, it is even more critical in SOAs because of the way that these environments support deployment of composite services on the fly." - SearchWebServices.com

"You need policy to have interoperability configuration and discoverable enforcement." - Developer

“Layer 7 Technologies, a leader in XML Security and Networking today announced successful Web Services Policy (WS-Policy) interoperability with leading Service Oriented Architecture (SOA) application and middleware vendors including SAP, IBM, BEA, Sun and Microsoft. WS-Policy is an emerging W3C standard for expressing the security, reliability and transactibility requirements of interacting Web services in an SOA.” - BUSINESSWIRE