在过去的十年中,树形结构的有线电视网已发展成为HFC结构。由于提供高级业务需要提高网络的质量、增强网络的可靠性和交互性,因此,这种变化是不可避免的。 对于大多数高级HFC网络,从二级站到光节点采用星形结构,而首站到二级站之间是一个环。 本文分析了这个环的传输层的可选方案,共列出并比较了四种基本选项。密集波分复用(DWDM) Over the past decade, tree-structured cable networks have evolved into HFC structures. This change is inevitable due to the need to improve the quality of the network and enhance the reliability and interactivity of the network by providing advanced services. For most advanced HFC networks, the star structure is from the secondary station to the optical node, and the ring between the primary station and the secondary station. This article has analyzed the options for the transport layer of this ring, listing and comparing four basic options. Dense Wavelength Division Multiplexing (DWDM)