| 摘要 |
Signaling from a mobile device is transparently tunneled through a cellular voice network to a Voice over Internet Protocol ("VoIP") core network so that multi-party calls, including conference calls and call waiting, can be managed entirely within the VoIP core network. The tunneled signals enable call control to be implemented in the VoIP core network and also establish a way to communicate requests, instructions, and call state. The signaling is transparent to the cellular network because that network does not receive and interpret the signaling. Instead, the cellular network's existing and unmodified control plane is repurposed by the mobile device by placing new, brief outgoing calls through the cellular network to the VoIP core network where the called party number (i.e., the caller-ID) encodes specific information. The VoIP core network immediately releases the new cellular call once the caller-ID is received and the encoded information is interpreted. |
