FGD or FG-D

Feature Group D. An MF signaling protocol, originally developed to support equal access to long distance services, capable of carrying one or two...

NOC

Network Operations Center. Carrier group responsible for the day‐to‐day care of a network.

Manual Transfer

A feature that enables the PSAP attendant to transfer incoming 9‐1‐1 calls by manually obtaining dial tone through use of the telephone switch or...