12 THE RAA” FUNCTION

08.203GPPRate Adaptation on the Base Station System - Mobile Service Switching Centre (BSS-MSC) InterfaceTS

On the IWF side of the A interface, the RAA" function shall convert between the A-TRAU format and a synchronous stream. FPS shall be performed by this function as well, see subclause 11.2. In transparent operation, the RAA" function shall handle the M1 and M2 bits as specified for the RA1′ function in 3GPP TS 04.21.

In non-transparent operation, the RAA" function shall map between the A-TRAU format and 290 bit blocks consisting of M1, M2 and 288 bits making up half of an RLP frame, see subclause 15.2 of this GSM TS.