A method and apparatus control receiving media data in a transmission system. A method of operating a receiving entity in the transmission system includes receiving packets for media data and information about a fixed delay associated with the media data. The method also includes identifying a requirement configured to guarantee that the packets for the media data are delivered to an upper layer of the receiving entity after the fixed delay, from the information about the fixed delay. The method further includes identifying a buffer size requirement for the receiving entity estimated based on the fixed delay and bitrate information associated with the media data; and delivering the packets to the upper layer of the receiving entity.