Progress and challenges for high speed optical access networks

This paper reviews the recent progress in high speed optical access networks with emphasis on passive optical network (PON) technologies. Overview of architecture options, key technologies, and main challenges for various systems, such as TDM-PON, WDM-PON, and OFDM-PON, will be discussed. One key factor to enable large scale deployment of next generation high speed PON system is the capability to cost effectively upgrade bandwidth on demand. Hybrid solutions, which combine multiple existing technologies, such as WDM-TDM PON or WDM-OFDM PON, can take advantages of volume effects of mature technologies to increase system bandwidth cost effectively. From practical point of view, hybrid systems are attractive since they can provide a flexible balance between performance and cost to support diversified applications.