The granularity of releases of the .NET Framework is outpaced by the evolution of the various standards around Web services. To combat this, Microsoft has released periodic updates to the .NET Framework that allow developers to build Web services that can continue to interoperate with new or updated standards. WSE 3.0 contains updates for WS-Security, WS-Addressing, and others.

WSE 3.0 is not just a security extension of the .NET platform. It supersedes the previous releases by adding the following interoperability features:

• Simplified Security Business data can be encrypted and digitally signed using Web services security via a "handler" defined in the policy file. Security policies, which support WS-Policy, are declarative and can be changed without rewriting the application codes.

• Sending Large Amounts of Binary Data WSE 3.0 now supports the W3C SOAP Message Transmission Optimization Mechanism (MTOM) specification, which is basically a new specification to send SOAP attachments (such as video files or pictures) in a simpler and more effective manner. This provides the benefit of reducing the size of SOAP attachments over the wire. MTOM support is a key interoperability feature for Java EE applications using JAX-WS.

• Support of WS-Trust, WS-SecureConversation, and WS-Addressing There are a few security enhancements that provide signature confirmation, opaque security tokens, and the ability to create encrypted tokens. It also supports re-establishing the secure session after the session has been lost or explicitly canceling a current secure session. This allows better interoperability with other service providers, including Java EE applications.

• Interoperability with Windows Communication Foundation New .NET clients using Windows Communication Foundation can interoperate with WSE 3.0 using Web services and WS* (such as Web services security and WS-Trust) security features.

If the goal is to build a Java-based Web service or client that uses any standards that have been introduced in the last few years (such as the ones mentioned here) and it needs to interoperate with .NET, it is highly recommended to implement the application using the Web Service Enhancements.