Recommendation ITU-T H.248.19 describes the functionality of a decomposed multipoint control unit,in particular the interface between a media controller and media processor which is based on Recommendation ITU-T H.248.1.This Recommendation contains guidelines for the use of a decomposed gateway that may support audio,video and data conferencing.This Recommendation contains packages for floor control,volume control,video windows,audio and video mixing for point-to-point,multi-cast and hybrid conferencing scenarios.This revision incorporates corrections to fix a duplicated binary Release Event identity and a duplicated Result parameter binary identity.