Comtech EF Data Vipersat SLM-5650A User Manual page 142

easy to quickly upgrade the feature options of a modem while it is running live
in the network, either on site or remotely.
FDMA Frequency Division Multiple Access – A technique where multiple users can
access a common resource (e.g. satellite) by each being allocated a distinct
frequency for operation. See also TDMA and STDMA.
FEC
Forward Error Correction – A process whereby data being transmitted over a
communications link can have error correction bits added which may be used at
the receiving end to determine/correct any transmission errors which may occur.
Flash
Non-volatile computer memory that can be electrically erased and repro-
grammed.
Forward Transmission path from the Hub site to a Remote site.
Path
FTP File Transfer Protocol – An application for transferring computer files over the
Internet. See also TFTP.
G.729 ITU standard for LD-CELP (Low Delay – Code Excited Linear Prediction)
voice encoding at 8 kb/s.
GIR Guaranteed Information Rate
Group ID
A number assigned to equipment which defines it as a member of a group when
addressed by the VMS burst controller.
GUI Graphical User Interface – A form of graphical shell or user interface to a
computer operating system or software application.
H.323 A protocol standard for multimedia communications designed to support real-
time transfer of audio (such as voice over IP) and video data over packet
networks. Quality of Service is a key feature of H.323. An alternative to SIP.
HDLC
High Level Data Link Control – A standard defining how data may be transmit-
ted down a synchronous serial link.
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