22.0533GPPRelease 17Service descriptionStage 1Tandem Free Operation (TFO)TS
The present document specifies the stage 1 description for the Tandem Free Operation (TFO) feature which provides the capability to avoid tandeming speech codecs in mobile to mobile speech calls. The primary aim is to realise improvements in speech quality. The TFO mode of operation could also be used to reduce inter-Mobile services Switching Center (MSC) transmission bandwidth requirements.
In analogy with ITU-T Recommendations I.130 , Stage 1 is an overall service description, from the service subscriber’s and user’s standpoints, that views the network as a single entity which provides services to the user.