GPRS introduces two new nodes
Serving GPRS Support Node (SGSN)
- at the same hierarchical level as the MSC
- keeps track of the location of a mobile station and handles access control
- connects to Base Station with Frame Relay
- connects to HLR with a Signalling System no. 7 (SS7) network
Gateway GPRS Support Node (GGSN)
- provides interworking with external packet switched networks
- connects to SGSN with an IP backbone
MSC: Mobile-services Switching Center
HLR: Home Location Register
Simulation of GPSR network
HLR: Home Location Register