The ITU-T Recommendations addressing transmission systems and media, digital systems and networks. See Table G-1 for selected G-series Recommendations. For a full listing of ITU-T Recommendations, see the contact information in Appendix A. Table G-1: G-Series Recommendations
| Recommendation | Description |
|---|---|
| G.168 | Digital network echo cancellers |
| G.169 | Automatic level control devices |
| G.651 | Characteristics of a 50/125 µm multimode graded index optical fibre cable |
| G.652 | Characteristics of a single-mode optical fibre and cable |
| G.653 | Characteristics of a dispersion-shifted single-mode optical fibre and cable |
| G.654 | Characteristics of a cut-off shifted single-mode optical fibre and cable |
| G.655 | Characteristics of a non-zero dispersion-shifted single-mode optical fibre and cable |
| G.665 | Generic characteristics of Raman amplifiers and Raman amplified subsystems |
| G.694.1 | Spectral grids for WDM applications: DWDM frequency grid |
| G.694.2 | Spectral grids for WDM applications: CWDM wavelength grid |
| G.702 | Digital hierarchy bit rates |
| G.703 | Physical/electrical characteristics of hierarchical digital interfaces |
| G.704 | Synchronous frame structures used at 1544, 6312, 2048, 8448 and 44,736 kbit/s hierarchical levels |
| G.705 | Characteristics of PDH equipment functional blocks |
| G.711 | Pulse code modulation (PCM) of voice frequencies |
| G.722 | 7 kHz audio-coding within 64 kbit/s |
| G.722.1 | Low-complexity coding at 24 and 32 kbit/s for hands-free operation in systems with low frame loss |
| G.722.2 | Wideband coding of speech at around 16 kbit/s using Adaptive Multi-Rate Wideband (AMR-WB) |
| G.723.1 | Dual rate speech coder for multimedia communications transmitting at 5.3 and 6.3 kbit/s |
| G.726 | 40, 32, 24, 16 kbit/s ADPCM |
| G.727 | 5-, 4-, 3-, and 2-bit/sample embedded ADPCM |
| G.728 | Coding of speech at 16 kbit/s using LD-CELP |
| G.729 | Coding of speech at 8 kbit/s using CS-CELP |
| G.729.1 | G.729 based Embedded Variable bit-rate coder: An 8-32 kbit/s scalable wideband coder bitstream interoperable with G.729 |
| G.983.1 | Broadband optical access systems based on Passive Optical Networks (PON) |
| G.991.1 | High bit rate Digital Subscriber Line (HDSL) transceivers |
| G.991.2 | Single-pair high-speed digital subscriber line (SHDSL) transceivers |
| G.992.1 | Asymmetric digital subscriber line (ADSL) transceivers |
| G.992.2 | Splitterless asymmetric digital subscriber line (ADSL) transceivers |
| G.992.3 | Asymmetric digital subscriber line transceivers 2 (ADSL2) |
| G.992.4 | Splitterless asymmetric digital subscriber line transceivers 2 (splitterless ADSL2) |
| G.992.5 | Asymmetric Digital Subscriber Line (ADSL) transceivers - Extended bandwidth ADSL2 (ADSL2+) |
| G.993.1 | Very high speed digital subscriber line transceivers |
| G.993.2 | Very high speed digital subscriber line transceivers 2 (VDSL2) |
