March 1997 was one of the important moments in the development of the field of video conferencing. ITU-T (Telecommunications Commission of ITU) issued a standard protocol for video conferencing on the local area network - H.323, Intranet connected to the video conferencing system provides interoperability standards, the manufacturers have launched in line with the standards of video conferencing products. Previously, the group video conferencing standard protocol for ISDN - H.320 has dominated the technology and product development in the area of video conferencing. The main difference between the two lies in the following aspects:
I. Networking structure
H.323 bus-type network structure will not be a temporary failure of a terminal and affect the entire meeting and network. H.320 master and slave star tandem structure may be due to single-point temporary failure, but there is no important node on the fault-tolerant backup mechanism leading to many network meetings are not functioning properly.
In this case,
2. Business development
H.320 is only based on the circuit-switched videoconferencing system is defined, so only in the transmission network platform to carry out standard videoconferencing applications, and can not be extended to a multi-media, multi-application platform.
H.323 technology can develop many multimedia applications that are not related to the underlying network transmission, such as multimedia video conference, multimedia monitoring, multimedia production scheduling command, remote enterprise training and education, multimedia call center, IP phone over the network, , Online video on demand and broadcast, you can use H.323 technology to a variety of applications and business superimposed on the same transport network platform, video conferencing is only one of its applications. In this case,
3. Performance and low cost
H.320 due to the traditional TV system conference technical system constraints, do not have the flexibility and rich functionality, and, whether H.320 terminal or H.320 MCU, its user stand-alone cost and user line usage costs are high.
H.323 uses advanced TCP / IP technology, while providing the same performance and more features, greatly reducing the cost of the user terminal and the user line costs, with a high cost performance