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Sun Microsystems took its Web services interoperability effort, code-named Tango, to Microsoft’s campus last week for another in a series of meetings where the two companies will learn to dance with one another in the Web services arena.

Microsoft hosted its second Windows Communication Foundation (also known as Indigo) Interop Plug-fest with Sun last week, and at least five Sun engineers attended the three-day event on Microsoft’s Redmond, Wash., campus to test interoperability between Sun’s Project Tango and WCF, said Arun Gupta, a Sun staff engineer, in a blog post. Other Sun staff participated remotely, he said.

Gupta, who attended the first WCF Plug-fest in November, said last week’s was bigger and better.

“We tested interoperability of implementations of WS-Addressing, MTOM [Message Transmission Optimization Mechanism], Reliable Messaging, Schema and WSDL [Web Services Description Language], Web Services Security 1.0 and Metadata Exchange,” said Gupta. “The source code of these implementations will be available in Glassfish and binaries in the Java Web Services Developer Pack in the future.”

Click here to read more about Indigo.

In a blog post from February, Harold Carr, a Sun engineer who also attended the WCF Plug-fest, said, “Sun Java Web Services [JWS] engineers are working with Microsoft Windows Communication Foundation [WCF] engineers to ensure interoperability of enterprise features such as security, reliable messaging and atomic transactions. At Sun, we call this work ‘Project Tango.’”

Carr said the interoperability testing “is accomplished by implementing a number of WS-* specifications and holding Plug-fests where our engineers work together for a week to test our implementations of those specifications.”

Moreover, Carr said the enterprise features being tested fall into four main categories: messaging, metadata, security and quality of service. Carr’s post describes how Sun provides interoperability support for all these categories through Web services standards.

In a document inviting developers to attend the WCF Plug-fest, Jorgen Thelin, a program manager for Connected Systems Standards at Microsoft, said, “The Windows Communication Foundation Interop Plug-fest is an ad-hoc, open forum for companies who have implementations of various Web Services protocols to meet with engineers from the Connected Systems Group and test against the upcoming version of Microsoft’s Windows Communication Foundation … product.”

In addition, Thelin, who was previously chief scientist and chief server architect at Cape Clear, said, “This plug-fest event is open to anyone who desires to participate and who can bring an implementation to test interoperability with Microsoft’s Windows Communication Foundation product in any or all of the following areas: Basic Messaging Scenarios using protocols: SOAP1.1 [Simple Object Access Protocol], SOAP1.2, WS-Addressing 2004/08, MTOM; Message Security Scenarios using WS-Security 1.0, WS-Security 1.1, WS Secure Conversation 2005/02, WS-Trust 2005/02, Username Token Profile (1.0, 1.1), X509 Token Profile (1.0, 1.1), SAML Token Profile (1.0, 1.1), Kerberos Token Profile 1.1; STS- Security Token Service scenarios; Reliable Messaging using WS-RM 2005/02; Transactions using WS-AtomicTransaction and WS-Coordination; and WS-Policy and WS-MetadataExchange are included in several scenarios.”

Dino Chiesa, a product manager in Microsoft’s .Net developer group, in a blog post described the Plug-fests as “get-togethers of the various organizations and companies who build Web services apps or tools, but the Web services libraries the apps and tools rely upon. The WS-* standards are a good start to getting ubiquitous interop, but to realize the benefit of standards, you need practical interop work. That’s where the plug-fests fit in. Microsoft has been sponsoring these get-togethers, as have other companies, for years. It is really paying off with usable interop today, and it should get even better tomorrow with simpler interop at higher levels of service, including transactions, security, reliability and so on.”

Meanwhile, Gupta said he “represented Sun for the interop using JAX-WSA [Java API for XML Web Services Addressing] APIs and implementation and achieved 100 percent interoperability. That means all the vendors who had a WS-Addressing client [IBM, JBoss, Microsoft and WSO2] were able to invoke Sun endpoints on all the required features. And Sun was able to invoke all the endpoints published [IBM, JBoss, Microsoft, WSO2, Apache Axis] for the required features. And invoking is just an understatement, since the report follows a rigorous XPath-based check on request and response messages, ensures all the messages (four of them) are received for a non-anonymous ReplyTo, checks the reference parameters in request and response, defaulting of FaultTo and all sort of features.”

Gupta said all the technologies Sun used in the Plug-fest will be using Glassfish as the container. Glassfish is Sun’s project to build a free, open-source application server that implements the newest features in the Java Enterprise Edition 5 platform.

“We, at Sun, care a lot about Web services interoperability and thus will be participating in the plug-fest to demonstrate interoperability with Indigo,” Gupta said.

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