(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.
Last updated: 1998-09-10
group ♦ Group 3 ♦ Group 4 ♦ Group Code Recording ♦ group identifier
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