PON ring architectures for truly shared LAN capability and dynamic bandwidth allocation for fiber wireless (FiWi) applications

Due to reduced operational and equipment costs, time division multiplexed (TDM)-based passive Optical Network (PON) access solutions including Gigabit PON (GPON) and Ethernet PON (EPON) have been widely accepted as a viable technology for the implementation of fiber-to-the-x (FTTx) solutions, and are being deployed globally. Users are increasingly requiring more bandwidth for high end applications and at the same time greater mobility. The convergence of fiber and wireless systems is seen as the optimum solution to offer the combination of the fiber capacity and the wireless mobility. PON has been proposed as a backhaul for wireless. Typical architectures are traditionally deployed as tree topologies. However, tree-based topologies have several inherent drawbacks such as inability to support a truly shared Local Area Network (LAN) capability among end users. In this paper, we propose scalable ring-based architectures that offer truly shared LAN capability as well as dynamic bandwidth allocation. These architectures are ring-based as well as hybrid, combination of tree-based and ring-based. These flexible architectures can be used as the back-haul to wireless by incorporating the base stations in the ONU locations. Our proposed hybrid PON ring architecture is scalable to 78 ONUs without the use of any amplifiers and in addition, the basic ring architecture and in turn the hybrid one is transparent to protocols and data rates and hence allows for greater BW flexibility as well as greater number of serviced end-users.