G

Gateway
    An entrance and exit into a communications network.  These may be large or small, and are
    technically electronic repeater devices that intercept and steer electrical signals from one network
    to another.   A hardware or software set-up that translates between two dissimilar protocols.

Gateway Protocol Converter
     An application-specific node that connects otherwise incompatible networks. Converts data
    codes and transmission protocols  to enable inter operability. (Contrast Bridge)

GFC - Generic Flow Control
    A field in the ATM header which can be used to provide local functions.  It has local significance
    only and the value encoded in the field is not carried end-to-end.

GHz - Gigahertz
    A measurement of the frequency of a signal equivalent to one billion, or one thousand million,
    hertz, or cycles per second.

Gigabits
    One thousand million bits.  One billion bits.  Or more precisely 1,073,741,824 bits.

Glare
    Glare occurs when both ends of a telephone line or trunk are seized at the same time for different
    purposes or by different users.

GMT - Greenwich Mean Time
     Zulu Time GMT is 6 hours later than Central Standard Time (CST in the northern hemisphere Winter)
    and 5 hours later  than Central Daylight-Savings Time (CDT in the northern hemisphere Summer).
    GMT (Zulu Time) is always the same  worldwide. Communication network switches are typically
    coordinated on GMT.

Gopher
     Internet public database browsing and searching program.

GOS - Grade of Service
    A quality of the signal along out customer lines and the amount of blocking due to the concentratable
    ration used for the customer's service.   A term associated with telephone service indicating the
    probability that a call attempted will fail or receive a busy signal, expressed as a decimal fraction.
    Grade of service may be applied to the busy hour or to some other specific period.

Grandfathered
    Something that has a right to be a thing, or own a thing, by reason of it being or owning that thing
    BEFORE laws or rules were introduced to formalize the process.

Grooming
    Managing bandwidth on a wide area, public or private network to use the long haul transmission
    facilities as effectively as possible.

Group Access Bridge
    A device that permits several people to converse with each other in a conference call, and which
    permits individuals to join or leave the conference call at will.

GS - Ground Start
     A way of signaling on subscriber trunks in which one side of the two wire trunk (typically the "ring"
    conductor of the Tip and Ring) is momentarily grounded (often to a cold water pipe) to get dialtone.
    A GS trunk initiates an outgoing trunk seizure by applying a maximum local resistance of 550 ohms
    to the tip connector.