US Patent 7760707 Voice over internet protocol application development framework

Applying services to calls involving subscribers to a telephony services provider includes receiving an indication of a call placed to or from a first call participant. The indication is received by a telephony services provider over a first signaling path of the call that is established between the telephony services provider and a first telephony proxy server that is controlled by a telephony infrastructure provider. Control signals configured to affect a voice path of the call that is established between the first telephony proxy server and a second telephony proxy server also controlled by the telephony infrastructure provider but associated with a second call participant are identified. The identified control signals are sent to the first telephony proxy server over the first signaling path and to the second telephony proxy server over a second signaling path that is established between the telephony services provider and the second telephony proxy server.