This Recommendation defines the interface used between the Call Management Server (CMS) and Provisioning Server (PS) for the exchange of service provisioning information. The interface employs a Web Service model. Specified in Web Service Description Language 1.1 (WSDL 1.1), the interface transports XML encoded objects within Simple Object Access Protocol 1.1 (SOAP 1.1) encoded messages over an HTTP 1.1 transport. This interface is secured via IP Sec.