RTP opens two ports for communication. One for the media stream (an even port number) and one for control (QoS feedback and media control) - RTCP. The port numbers are not hard defined, it depends very much upon the application.

H.263 is a video compression standard originally designed as a low-bitrate compressed format for videoconferencing. It was developed by the ITU-T Video Coding Experts Group (VCEG) in a project ending in 1995/1996 as one member of the H.26x family of video coding standards in the domain of the ITU-T.

This SonicWALL signature identifies legitimate Real-Time Protocol (RTP) with Encoded Payload traffic over UDP.