Research And Design The Streammedia Internet

As a result of the traditional TV adopting the reception of the single-mode, user can't demand program. Because of the valuable cost, complex fixing and no free using, it is hard to use set-top box broadly by user. For Convergence of the three networks (Telecommunications and computer networks, radio and television network) has gradually become a reality along with the rapid developing of network technology, streaming media has a very broad foreground.At the same time, people are dissatisfied with the multimedia form of single"download-playback". But one can hope the multimedia forms of playing program as transmitting program and demanding,watching,previewing,regressing program accord with the will. The flow transmitting playing of streaming media is just to meet the demands of people. So streaming media network based PC or mobile telephone will has a beautiful future.In this background, this thesis describes General framework of streaming media network firstly. Then it research two core fields of streaming media which are transmitting and playing of real-time streaming media.1. This thesis analyse the streaming media technology and research some main protocols for streaming media. It finally select the RTP/RTCP protocol after carefully comparing. RTP/RTCP protocol is designed and implemented based on researching in detail and application environment of the thesis. Many crucial technologies are adopted in process of implementing RTP/RTCP protocol.(1)Big load data (more than 1452 bytes) is partitioned and encapsulated in the application layer segmentation in order to fit Maximum Transmission Unit of internet by using RTP header extender.(2)Impact of jitter is compensated by using jitter buffer mechanisms.(3)Lost packet is re-transmitted for the sake of media playing more fluently according to Internet circumstance.2. The main protocol of TCP and UDP in transmitting layer is not adapt to transmitting stream media. So this thesis researched a new transmitting protocol of RUDP. It is added many functions on the basis of UDP, such as improved reliability, flow control, error control etc. So it is able to meet the need of strong real-time transmission and high transmitting quality in a given network bandwidth circumstance and find out the better balance point between the network bandwidth and transmission quality.3. The player of streaming media is implemented in the type of AxtiveX Control. So it can be used by some programs coded with other program language. The player can play streaming media fluently by using similar cycle link Table-data buffer technology, because data buffer can decrease the influence of delay jitter.