The connection between the aggregation points in the network and metropolitan backbone is being called backhaul. Those traffic aggregation points include mobile phone base stations, wireless access points, business and home Ethernets as shown in Figure 1. In future mobile applications requiring high-speed wireless access will distribute wider making mobile phone operators switch from current T1/E1 copper lines to new architecture that can support high capacity. Apart from new architecture, local mini mobile base stations – “femtocells” will spread wider requiring high speed backhaul service. This requirement can be met by use of the PON architecture. It can provide broadband access with speeds up to hundreds of megabits per second, with low latency. While having greater to existing solutions capacity, PON can offer necessary synchronization, flexibility, and possible scalability.

Figure 1. Backhaul service possibilities.

After quick research, it is clear that WDM-PON is preferred candidate for this scenario. It supports multiple data formats and data rates, while providing high capacity access for ONUs/ONTs. As an alternative it is possible to use currently developing OFDM-PON (Orthogonal Frequency Division Multiplexing PON) with management and services flexibility.