Configure WebSphere DataPower SOA Appliance and WebSphere Application Server to implement WS-Policy for SOA service governance. User credentials are transformed in an LPTA common token format for authorization and single-sign-on between DataPower and an application hosted on WebSphere Application Server. Offloading policy management to DataPower lets WebSphere Application Server provide better application-level functionality, while DataPower provides enterprise-wide, high-performance service governance.
http://www.ibm.com/developerworks/websphere/library/techarticles/0911_rasmussen/0911_rasmussen.html
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