IN-BAND QUALITY DATA

A method for processing, at a receiving device, a media stream from a transmitting device, the media stream being in accordance with a media streaming protocol, the method comprising: receiving a packet of the media stream, wherein the packet comprises a data structure defined by the protocol, that data structure comprising: data of a first type, the first type being associated with a first type identifier in accordance with the protocol; and a type identifier field for specifying a type of data contained within the data structure, the type identifier field being set to a second type identifier, the second type identifier being different to the first type identifier; and transmitting a packet to the transmitting device, the transmitted packet being capable of indicating whether or not the data can be processed in a data structure having the type identifier set to the second type identifier.