一、城域传输网的现状分析 近年来,通信领域的业务,尤其是对宽带传输的需求呈指数上涨,人们对带宽的需求导致了DWDM(密集波分复用)技术首先在省际干线上大量使用,以缓解骨干网的传输压力。例如,中国电信省际干线的平均带宽已远远超过了10Gbit/s。同时,随着xDSL、线缆调制解调器以及高速吉比特以太网等宽带接入技术的日益普及,终端用户的接入速率正迅速地从过去的几十kbit/s First, the analysis of the status of metro transport network In recent years, the business of communications, especially the demand for broadband transmission rose exponentially, the demand for bandwidth led to DWDM (Dense Wavelength Division Multiplexing) technology first in the inter-provincial trunk Massively used to ease the transmission pressure of the backbone network. For example, the average bandwidth of China Telecom inter-provincial trunk lines has far exceeded 10Gbit / s. At the same time, with the increasing popularity of broadband access technologies such as xDSL, cable modems, and high-speed Gigabit Ethernet, end-user access rates are rapidly moving from tens of kbit / s