Introduction
The WS-Trust specification defines extensions that build on WS-Security to provide a framework for requesting and issuing security tokens. Particularly, WS-Trust defines the concept of a security token service (STS), a service that can issue, cancel, renew and validate security tokens, and specifies the format of security token request and response messages.
Please look at the PicketLink Quickstarts for the PicketLink STS web application. The quickstarts are useful resources where you can get configuration files.