There is a tradeoff between energy saving and performance in green networks since energy saving is generally achieved by rerouting packets along a substitute path with more hops to put low-load nodes to sleep or assembling several packets before sending them to reduce the number of wake and sleep time intervals of transmitting ports. Fiber-Wireless (FiWi) access networks must be able to transport video traffic in an efficient way due to the fact that video will account for the largest part of global consumer traffic. To reduce the energy consumption of FiWi networks and guarantee the performance of video applications, issues related to the energy-efficient Quality-of-Service (QoS) support for video delivery in IEEE 803.3az Energy Efficient Ethernet (EEE)-based FiWi access networks are addressed in this paper. We extend EEE packet coalescing by considering QoS priorities and the shared nature of FiWi networks and improve the QoS support for video delivery by proposing a green QoS differentiated routing strategy. In addition, to better evaluate the performance of our scheme in a real-world setting, we carry out traffic measurements for the research on EEE-based networks and use them in our simulations. Our results show that the proposed scheme can effectively guarantee video delivery and reduce the energy consumption of EEE-based FiWi access networks.
© 2011 IEEEPDF Article