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.