GPRS Roaming Exchange - Technical Implementation

Technical Implementation

Usually, GRX is based on a private or public IP backbone and uses GPRS Tunnelling Protocol on the session layer (OSI Layer Five) between the visited PLMN(Public Land Mobile Network) and the home PLMN. Each GRX operator will have a network consisting of a set of routers and links connecting to the GPRS networks, moreover the GRX network will have links connecting to other GRX nodes in peer model.

The GRX operator can therefore act as a hub, allowing a GPRS subscriber to interconnect with many roaming partners without the need for dedicated links. For operators this is advantageous in that it allows quicker implementation of roaming partners, faster time to market for new operators and lower capital expenditure seeing as it is a scalable solution depending on bandwidth and quality of service requirements. Because the interconnection between the visited PLMN and home PLMN uses private GRX networks there is also no need to maintain Internet Protocol Security (IPsec) tunnels over the public internet.