Before revision: With a Security Token Service (STS), the RP is redirected to an STS , which authenticates the RP and issues a security token granting access, instead containing a set of claims about the client's identity, which it can present to the RP.
After revision: With a Security Token Service (STS), the RP redirects clients to an STS , which authenticates the client and issues it a security token granting access instead containing a set of claims about the client's identity, which it can present to the RP.