Glossary

G

GbE / GigE
Gigabit Ethernet
Generator
An “engine-generator” is the combination of an electrical generator and an engine, mounted together to form a single piece of equipment, and used to ensure power continuity in the event of a failure in main power supply.
GFP
Generic framing procedure
GGSN
Gateway GPRS support node: a router within GPRS networks for disassembling GTP tunnels and forwarding IP packets to internet or mobile operator servers.
GMPLS
Generalised multi-protocol label switching
GPON
Gigabit passive optical network: encapsulates traffic in a version of the SDH-compatible GFP to support real-time services such as on-demand television.
GPRS
General packet radio service
GRX
Global/GPRS roaming exchange node: GRXs interconnect with GPRS networks to facilitate global roaming coverage. Based on the GSM Association’s IR.34 recommendation, it takes the form of a centralised IP-routing network for interconnecting GPRS and 3G networks. GRX can be implemented on a private or public IP backbone and transports GPRS roaming traffic via the GPRS tunnelling protocol (GTP.) As traffic is aggregated at the regional GRX level, carriers require only a connection to a local point of presence to enable global roaming. GRX networks interconnect to create a tier of the internet through which carriers can exchange IP traffic generated by roaming customers. Instead of building bilateral links between carriers, GRXs may serve as a hub, enabling carriers to link up with several GRXs that interconnect to provide roaming between carriers. This allows for faster implementation and rapid time to market for new roaming partnerships and operators.
GSM
Global system for mobile communication
GTP
GPRS tunnelling protocol: used to encapsulate mobile subscriber data traffic between SGSN and GGSN nodes, in non-roaming and roaming situations.