3.2.5.1 Registration

The client MUST register with the server before making other service requests. If a service request is made before the registration, a fault response message MUST be returned with the fault code 304, indicating that the registration is required.

The Registration message is a mechanism for exchanging the shared secret key used in message data encryption/decryption and message integrity protection and verification. The client MUST generate the shared secret key for the registration.