GPRS (General Packet Radio Service) Question:

A mobile device is programmed with one or more Access Point Names which are commonly referred to as the APN's. An APN consists of a fully qualified DNS name e.g. globalguideline.com When a GPRS device wants to talk to globalguideline.com, the SGSN does a DNS look up and resolves the name to the correct GGSN. You could have multiple APN's programmed into your phone so you are not limited to a single service or GGSN.