3.2.3 Initialization
Before any protocol messages can be exchanged, a requestor IP/STS MUST exchange metadata with relying parties and initialize federation partner records for them in local configuration data, as specified in section 3.1.1.2.
To service protocol messages, a requestor IP/STS MUST be listening for requests at the URL it has advertised to federation partners.
To service wsignin1.0 request messages, a requestor IP/STS MUST be able to contact user authentication and account services in its local security realm to obtain the authenticated user identity and optional attributes necessary for constructing a security token.
The protocol does not require specific initialization on receipt of a protocol message.