Patent ID: 7050414

Claim:
A method comprising the steps of: directing a call intended for a mobile to a virtual tandem switch; querying, by the virtual tandem switch, a home location register to obtain call information for the mobile; converting control messages at a first location, between a packet-based protocol and a non-packet-based protocol; converting voice messages at a first location, between a packet-based protocol and a non-packet-based protocol; converting control messages at a second location, between a packet-based protocol and a non-packet-based protocol; converting voice messages at a second location, between a packet-based protocol and a non-packet-based protocol; and setting up the call to the mobile over a packet-based transport network; wherein the virtual tandem switch supports protocols selected from the group consisting of ISUP, Primary Rate Interface (PRI), and Transaction Capabilities Application Part (TCAP), ATM UNI 3.1/4.0, Internet Protocol Device Control (IPDC), IPDC+, Media Gateway Control Protocol (MGCP), H.248 , ISUP+, and bearer independent call control (BICC).