It is a WS-* specification and OASIS standard that provides extensions to WS-Security, specifically dealing with the issuing, renewing, and validating of security tokens, as well as with ways to establish, assess the presence of, and broker trust relationships between participants in a secure message exchange.

The WS-Trust specification was authored by representatives of a number of companies, and was approved by OASIS as a standard in March 2007.

Using the extensions defined in WS-Trust, applications can engage in secure communication designed to work within the Web services framework.

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