"Even if SOAP/WSDL was the right answer, we will never be able to adopt a single type of service. All technologies have tradeoffs associated with them, and we should never assume a homogenous enterprise environment (not to mention the massive cost of switching everything over). Because UDDI has been designed around the concepts of SOAP/WSDL, it has failed to evolve and address this problem.

"There are yet more problems with UDDI, though. A lot of effort has been spent on seldom-required use cases. For instance, it's often recommended that people use it at runtime to dynamically look up services. In reality, this is often dangerous, and hardly ever done. You can easily end up with a service you don't want, whether it's because the functionality is slightly different, the service is slower, or it lacks redundant backups.

"On top of this, UDDI is also quite hard to use. It seems people were so confused, the technical committee had to write another long document explaining how it could be used as a registry with SOAP/WSDL services. Then Systinet had to write another long document called the Governance Interoperability Framework to make it actually possible for inter-vendor communication using UDDI.

"Where does this leave us? We need to leave this whole stack behind. Registries need to be more agile, easier to use, and focus on things that matter for SOA projects today. We've been pioneering a new approach with Mule Galaxy. It uses a simple, extensible services model which enables you to reap the benefits of registries—service visibility, contract management, policy management, etc.—while remaining in a heterogeneous environment.

"It also uses a new type of registry API based on the Atom Publishing Protocol (AtomPub). This API, which is built on Atom (the successor to RSS), enables integration using a simple, RESTful mechanism. This RESTful approach, combined with our flexible services model, reflects the way that enterprises actually do business, not some vendor-imposed theory."

Do you think Diephouse's remarks are inciteful or insightful? In any case, here's Microsoft's counterpoint. Read that, too, and tell us who has the right of it.