| Annex M | |
| Status: | In force |
| Version: | 1.2 |
| Version Date: | April 2004 |
| Organization: | ITU-T |
| Related Standards: | G.992.5 |
| Domain: | telecommunications |
| License: | Freely available |
| Website: | https://www.itu.int/rec/T-REC-G.992.5/ |
Annex M is an optional specification in ITU-T recommendations G.992.3 (ADSL2) and G.992.5 (ADSL2+), also referred to as ADSL2 M and ADSL2+ M. This specification extends the capability of commonly deployed Annex A by more than doubling the number of upstream bits. The data rates can be as high as 12 or 24 Mbit/s downstream and 3 Mbit/s upstream depending on the distance from the DSLAM to the customer's premises.[1] [2]
The main difference between this specification and Annex A is that the upstream/downstream frequency split has been shifted from 138 kHz up to 276 kHz (as in Annex B/Annex J), allowing upstream bandwidth to be increased from 1.4 Mbit/s to 3.3 Mbit/s, with a corresponding decrease in download bandwidth.
This standard was approved for deployment on Australian networks by the Australian Communications Industry Forum (ACIF).