Microsoft technical comment: Develop interoperable approach notspecific to SCA for callbacks

[Michael Champion <Michael.Champion@microsoft.com>]

The following is a Microsoft technical comment about the SCA Web Service Binding specification that is being developed by OASIS Service Component Architecture / Bindings (SCA-Bindings) TC.

Based on the section 5 of the Web Service Binding specification v1.1, CD 03, the SCA Bindings TC defines a protocol for Web Service callbacks built on WS-Addressing and policy assertions based on WS-Policy. While WS-Addressing and WS-Policy are appropriate technologies, the work of defining a Web Service callback standard is best done by the appropriate Web Services working groups in OASIS in the broadest scope possible. This will foster a general interoperable mechanism for all architectures and programming models that use standard Web Services protocols on the wire.

Specifically, The Web Service Binding spec sections 5.3.1 to 5.3.4 introduce the SCA-specific policy assertion WSCallback to signal the use of SCA callback protocol. In addition, the Section 7.4 of the SCA Assembly Model specification v1.1, CD 03 defines WSDL callback extension sca:callback. As with the previous point, Microsoft respectfully believes that an interoperable approach which is not specific to SCA should be adopted with the help of other OASIS technical committees who specialize in Web Services standards. Such interoperable callback mechanism would allow bidirectional SCA services to communicate with a wide range of non-SCA services such as those implemented by JAX-WS or WCF frameworks. Without it, SCA services would only be able to use bidirectional communication with other SCA services, but not with Web Services generally.

As OASIS members, we are all highly committed to open standards and industry-wide interoperability. Such interoperability is best served by broadly creating Web Service wire protocol standards that are common among as many diverse programming environments and platforms as possible. In that spirit, SCA Bindings TC is best served by using existing Web Services standards, or where needed, by creating new Web Service standards in a broader context in OASIS.

Michael Champion
OASIS voting member - Microsoft Corporation