In a multimedia streaming network where a client has a receiver buffer to store a plurality of packets received from a server so as to compensate for the difference between data transmission amount by the server and data usage amount by the client, the server should be able to adapt the data transmission rate based on the status of the receiver buffer. For rate adaptation purposes, server reconstructs a list of packets in the receiver buffer based on information provided by the client. The information signaled to the server is indicative of the next packet to be decoded in the client. The information can be the sequence number of the next packet to be decoded, the DON number of the next NAL unit to be decoded, or the sequence number of the packet carrying the next NAL unit to be decoded and the DON indicative of the decoding order of that next NAL unit.