Method for providing third-party call control reuse of telephony features

Third-party call control functionality from a user's application platform makes use of existing feature logic and feature interactions within the telephony switch controlling the telephonic device being proxied. A PC coupled to a web-based server and a phone are provided at the user end. An interface includes a server. At the switch end, there is signaling proxy equipment such as a CSTA Manager and a local signaling manager. A call processing core is made up of a Call Engine that may include a 3rd Party Make Call Control (3PCC) API. Call services are provided through the switch, which may include a CSTA service as well as other services.