Value Name,Long Name,Mux Category,Reference ack,Positive acknowledgement,IDENTICAL-PER-PT,[RFC4585][RFC8859] app,Application-defined parameter,SPECIAL,[RFC4585][RFC8859] ccm,Codec Control Commands and Indications,IDENTICAL-PER-PT,[RFC5104][RFC8859] nack,Negative Acknowledgement,IDENTICAL-PER-PT,[RFC4585][RFC8859] trr-int,Minimal receiver report interval,IDENTICAL-PER-PT,[RFC4585][RFC8859] 3gpp-roi-arbitrary,Video region-of-interest (ROI) arbitrarily selected by the endpoint,IDENTICAL-PER-PT,[3GPP TS 26.114 v16.3.0][Ozgur_Oyman] 3gpp-roi-predefined,Video region-of-interest (ROI) pre-defined by the sender and selected by the endpoint,IDENTICAL-PER-PT,[3GPP TS 26.114 v16.3.0][Ozgur_Oyman] 3gpp-delay-budget,Available or requested delay budget specified in milliseconds,IDENTICAL-PER-PT,[3GPP TS 26.114 v16.3.0][Ozgur_Oyman] 3gpp-viewport,Viewport feedback for viewport-dependent 360-degree video,IDENTICAL-PER-PT,[3GPP TS 26.114]