Patent ID: 8553681

Claim:
A method comprising: detecting an off-hook condition of a calling station, the calling station associated with a telephone number of the calling station; subsequent to detecting the off-hook condition, receiving dialed digits from the calling station, the dialed digits indicating a call request and a telephone number of a called party; providing a request to a routing database, the request including at least a portion of the telephone number of the called party; receiving in response to the request an identity of a gateway to the called party; sending a first signaling message over a packet-switched network to the gateway using the identity of the gateway, the first signaling message including the telephone number of the called party; receiving the first signaling message at the gateway; formulating an SS 7 signaling message in response to the first signaling message, the SS 7 signaling message including the telephone number of the calling station and the telephone number of the called party; sending the SS 7 signaling message from the gateway over a connection to a public switched telephone network (PSTN) system; receiving at the gateway over the connection to the PSTN system an indication that the called party is at least one of busy or available; when the indication received at the gateway indicates that the calling party is busy, sending a second signaling message from the gateway over the packet-switched network indicating the called party is busy; when the indication received at the gateway indicates that the called party is available, sending a third signaling message from the gateway over the packet-switched network indicating the called party is available; recording billing information associated with the call request.