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RTP/RTCP (Real-time Transport Protocol/Real-time Control Protocol) are independent of the underlying transport and network layers, they are generally implemented based upon datagram-oriented protocols, for a instance, RTP/RTCP are usually implemented based on UDP in a TCP/IP network environment, while based on IPX (Internetwork Packet eXchange) in a SPX/IPX network environment. But as for the situation that only a octet-stream-oriented protocol is provide, the situation that the lost and disorder of data packets are somewhat scarce or the situation that more centralized control is required, it is necessary or practicable to exploit protocols such as TCP which is stream-oriented to implement RTP/RTCP. One of the representative applications is a video conference system based on TCP. As a stream-oriented protocol is employed to implement RTP/RTCP, there is a most major concern is how to accomplish unicast and multicast. This paper present a scheme that use a mixer defined in RTP/RTCP to fulfill multi-point transmission based on octet-stream-oriented protocol. According to this scheme, RTP/RTCP to fulfill multi-point transmission based on octet-stream-oriented protocol. According to this scheme, RTP/RTCP data are transmitted between each station and the mixer while the mixer provides an analysis about RTCP data, and the logical RTP/RTCP framing is performed by each station and the mixer in conformity to the payload type. Considering the characteristic of real-time video data stream, this paper provides a analysis on a exemplary video conference system which uses TCP-based RTP/RTCP to transmit real-time video and audio data. Moreover, a scheme to interconnect between such a octet-stream-oriented protocol based implementation and a datagram-oriented protocol based one is presented, and a discuss about the practicability to combine this implementation to a special simplified RSVP (Resource reSerVation Protocol) also is given forth.
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