Definition - What does G.7xx mean?
G.7xx refers to a suite of the International Telecommunications Union for Telecommunications (ITU-T) standard for audio compression and decompression. They are used in digital transmission systems and for coding analog signals into digital. This family of standards is included in the G series ITU recommendations.
The specifications in G.7xx family include G.711, G.721, G.722, G.723, G.26, G.728, G.729, etc.
Techopedia explains G.7xx
G.7xx is an ITU-T standard, which includes G.711, G.721, G.722, G.726, G.727, G.728 and G.729 for audio compression and decompression. They are widely used in cellular and Internet telephony including Voice over Internet Protocol (VoIP) communications.