But SAML was taken further. WS-Security SAML Token Profile allows the use of SAML tokens in SOAP messages secured with WS-Security. And WS-Trust and its Secure Token Service standardized the mechanism to obtain or exchange SAML (or other) tokens.
The STS is a standard (web) service to obtain such a SAML token: 1) through standard authentication mechanisms or 2) by exchanging one token for another (SAML to SAML, non-SAML to SAML or SAML to non-SAML).
But transferring SAML tokens between domains means the exchange of information between heterogeneous organizations. The SAML standard does not define how attributes within the SAML tokens should be named nor what their content should exactly look like. Every organziation is free to specify how information is structured in a SAML token:
- what information or attributes is contained in the SAML token: name, cost center, department, ...
- how the atrributes should are named, e.g. LastName or lname?
- how the information in the attributes is represented
Another integration challenge!
Note: Microsoft prefers the use of the term claim