High-speed broadband circuit switching system architecture

This paper considers the speed of communication where NTSC and HDTV video signal is encoded into digital forms, and proposes a high-speed broadband circuit switching system which realizes the integrated services covering communication services and distribution services. The former include the end-to-end communication such as TV conference and the video retrieval such as image inquiry system, and the latter includes the CATV. The proposed method has the following features: (1) The communication services and the distribution services are distinguished by using layer 3 of I interface protocol. The video channel selected by the subscriber is transferred between the subscriber and the service processing node of the video distribution system, using the high-level layer signal; (2) considering the uncertain demand, a building block structure is adopted, where the unit is the small-scale independent switching and distribution module with several tens to several hundreds of subscribers; (3) the load-function distributed control scheme is adopted. In the communication services, the functions are divided into the modules of subscriber accommodation, intermodule connection, inter-office signal processing and system management. In the distribution services, the divided modules such as the selection of video channel and the interface processing to the video operation center are executed in the almost complete processing within the module, which helps to reduce the communication traffic between modules.