Research And Implementation Of Video Conference System's Qos Based On Terminal

With the Internet's development, and audio and video codec technologies mature, more and more people wish to carry out video communication anywhere, anytime.And video conferencing systems use with video and audio compression technology and multimedia communication technologies in support of the people in real time distance exchange and sharing of information,so people can conduct collaborative work no matter where they are. It is for the timely convening of workshops, disseminating important information, with less cost and time.It's consistent with the need of modern communications,such as convenient, fast multi-media sharing, large amount of information and interactive requirements.But video conferencing is different from traditional data applications, it's real-time applications, not only consume a large amount of bandwidth, but also requre less network transmission delay, jitter and packet loss rate. Especially for high-definition video streaming process, more network transmission rate and higher bandwidth requirements.While the network transmission rate is too low will affect the real-time video transmission,and if the network transmission bandwidth is not enough, packet loss rate will increase that likely to affect the quality of video transmission.To solve the above problems, this subject is researched on the video conferencing system's QoS mechanism, and broadly understood of the appropriate technology.The author combines with the video conferencing software system which developed by the laboratory, designs a QoS agent module which based on video conferencing system terminal, to achieve this proposed. This module, both as part of the video conference system terminal, and as the video conference as part of the video quality assurance system, its role is surveilling the video conferencing terminal quality of service, and also responsible for interacting with the QoS server to achieve both QoS signaling transmission, and the order execution. This article focus of the QoS guarantees which base on the terminal. These QoS guarantees have their application environment and scenario, we design QoS guarantees there is no absolute guarantee of functionality, but the network conditions permitting, the overall situation with the QoS server layout, biased in favor of video conferencing services to achieve the priority services. Of course, video conferencing systems to enhance their performance to ensure quality of service is the key point. This congestion control from the terminal has been designed so as to seek a better way to ensure that our quality video conferencing services to meet the user experience requirements. In order to distinguish the normal data applications and audio and video data applications, the system will achieve under the IP header DSCP (DS code point) to choose to provide specific quality of scheduling forwarding services to ensure that when the network carrying the business model is higher, giving priority to ensuring the video stream transmission forwarding, so to ensure quality of service of video conferencing.