Passive optical networks has been considered to be one of the most promising solutions for access networks due to its broad bandwidth and low-cost infrastructure. Especially, spectrum sliced wavelength division multiplexed passive optical network (WDM-PON) can be an attractive and cost effective solution to satisfy the growing worldwide demand for transmission capacity in the next generation fiber optical access networks. Traditional WDM systems have multiple transmitter lasers operating at different wavelengths,which need to be wavelength selected for each individual channel operated at a specific wavelength. The strength of spectrum sliced WDM-PON technology is use of one common broadband seed light source and its ability to place electronics and optical elements in one central office (CO), in that way simplifying the architecture of fiber optical network. there are two major factors that will influence the telecommunication networks of the future. The first one is the need to support high bandwidths and low latency and the second one is to use an architecture that is both cost and energy efficient. In fiber optical networks latency consists of three main components which adds extra time delay: the optical fiber itself, optical components, and opto-electrical components. Therefore, for the service provider it is extremely important to choose best network components and think on efficient low latency transport strategy.