A method of integrating a circuit switched radio telecommunications network with a packet switched data network by using an interworking function, said circuit switched network having a circuit switched serving node, said circuit switched radio telecommunications network being an ANSI-41 radio telecommunications network wherein the circuit switched serving node is a mobile switching center (MSC), and said packet switched data network having a packet switched serving node and said packet switched data network being a General Packet Radio Service (GPRS) packet data network wherein the packet switched serving node is a serving GPRS switching node (SGSN), said interworking function being A GPRS-visitor location register interworking function (GPRS-VLR IWF), said method comprising the steps of:
- defining an ANSI-136 radio resources management sub-layer including a ANSI-136 medium access control (MAC) in the ANSI-41 radio telecommunications network for providing GPRS packet data network higher layer services;
- providing a first interface between the MSC and the GPRS-VLR IWF;
- mapping in the GPRS-VLR IWF, signaling from the MSC into signaling in a standard GPRS network protocol;
- interfacing the mapped signaling with the SGSN utilizing a CPRS standard Gs/Gd interface;
- connecting to the MSC, a GPRS/ANSI-136 base station which operates in accordance with both ANSI-136 standards and GPRS standards;
- receiving in the MSC, a circuit switched call for a mobile station while the mobile station is involved in a GPRS packet data transaction;
- utilizing, by the MSC, the first interface and the GPRS-VLR IWF to request the SGSN to page the mobile station;
- paging the mobile station by the SGSN;
- receiving in the SGSN, a page response from the mobile station;
- informing the MSC that the page response was received from the mobile station;
- and
- completing the circuit switched call from t MSC to the mobile station through the GPRS/ANSI-136 base station.