ITU G.992.4 is a standard for splitterless ADSL2 with data rate mandatory capability reduced to 1.536 Mbit/s downstream and 512 kbit/s upstream. It is also referred to as G.lite.bis.
See also ADSL ADSL2+ List of interface bit rates
References
External links ITU-T Recommendation G.992.4 : Splitterless asymmetric digital subscriber line transceivers 2 (splitterless ADSL2)