An International Telecommunications Union (ITU-T) standard for for audio (speech) compression and decompression that is used in digital transmission systems, and in particular, used for the coding of analog signals into digital signals.
G.723 is an ITU-T standard codec that uses Adaptive Differential Pulse Code Modulation (ADPCM) standard for speech codecs on a 24 and 40 kbps channel. NOTE: G.723 was first introduced in 1988. In 1990 this standard was folded into G.726 along with G.721. (See also ADPCM).
See G.7xx for more information on how these standards are used in telephony networks.