随着社会经济和科技的飞速发展,通信网络正在发生深刻的变化,电信业务正在逐渐从传统的以电话业务为主的窄带业务向集语音、高速数据和图像为一体的多媒体宽带业务发展。多媒体通信已成为建立公用宽带网的主要动力。传统电话网将不可避免要过渡到以数据业务、特别是IP业务为中心的下一代电信网,这些都对电信网的宽带化提出了迫切的要求。 With the rapid development of social economy and science and technology, profound changes have taken place in the communication network. The telecommunication services are gradually evolving from the traditional narrowband service based on telephone service to the multimedia broadband service integrating voice, high-speed data and images. Multimedia communications has become the main driving force behind the establishment of public broadband networks. The traditional telephone network will inevitably have to transition to the data services, especially the IP-based next-generation telecommunications network, which all put forward urgent requirements for the broadband of the telecommunications network.