Energy Efficiency in Future PONs

There is a still increasing tendency to give energy efficiency a high priority, even in already low energy demanding systems. This is also the case for Passive Optical Networks (PONs) for which many different methods for saving energy are proposed. This paper uses simulations to evaluate three proposed power saving solutions for PONs which use sleep mechanisms for saving power.

The discovered advantages and disadvantages of these methods are then used as a basis for proposing a new solution combining different techniques in order to increase the energy efficiency further. This novel solution is also presented in this paper. All simulations are done using OPNET Modeler where an EPON model is implemented with the necessary mechanisms for simulating basic functionality and for expanding the model with sleep methods.

The individual sleep methods are implemented on top of the basic EPON model, making it easy to switch between them and to let each method seamlessly be an integrated part of the EPON model without affecting other sleep methods or the normal EPON functionality. For simulating different kinds of approximately realistic traffic patterns, traffic generators are implemented in an easy interchangeable and customizable way, making it possible to simulate both generic traffic following general traffic patterns and individual types of traffic following documented real life traffic patterns.