This TS defines rate adaptation functions to be used in PLMN Base Station Systems (BSS) transcoders and IWF
The number of Base Station System - Mobile-services Switching Centre (BSS - MSC) traffic channels supporting data rate adaptation may be limited. In this case some channels may not support data rate adaptation. Those that do, shall conform to this TS.
This specification should be considered together with TS 44.021 to give a complete description of PLMN rate adaptation.