Group 4

<protocol, compression> (G4) The CCITT fax protocol which uses data compression and allows a variety of file types (e-mail, pictures, PostScript, etc.) to be transmitted over digital (ISDN) telephone lines.

The Group 4 protocol was published by CCITT in 1993. Full details of the protocol are available from ITU-T.

See also Group 3.

Nearby terms:
gronked « group « Group 3 « Group 4 » Group Code Recording » group identifier » Group Separator