The GFGUB enables the FE/GE transmission on the Abis interface.
The GFGUB performs the following functions:
Provides IP routing
Provides the routing-based backup and load sharing
Provides eight FE ports or two GE ports logically, which are used for IP transmission
Provides Tributary Protect Switch (TPS) function to enable switchover between the physical links of the active and standby boards.