GPRS network is based on the existing GSM network to achieve.
In the existing GSM network need to add some nodes, such as GGSN (Gateway GPRS supporting NODE,GPRS Gateway support node) and SGSN (serving Gsn,gprs Service support node).
GSN is the most important network node in GPRS network. GSN has a mobile routing management function, it can connect various types of data networks, and can be connected to GPRS registers.
GSN can complete data transfer and format conversion between mobile terminals and various data networks. GSN can be a stand-alone and standby similar to a router, and can be integrated with MSc in GSM. There are two types of GSN: one is SGSN (serving GSN, service GSN), the other is GGSN (Gateway GSN, Gateways GSN), and the main role of SGSN is to record the current location information of the mobile terminal, And between the mobile terminal and GGSN to complete the move packet data sent and received.
GGSN is primarily a gateway that can connect to a variety of data networks, such as ISDN, PSPDN, and LAN. In some literatures, the GGSN is called GPRS router. GGSN can transfer the GPRS packet packets in GSM network to the remote TCP/IP or X.25 network by the packet packets. (Computer science)