IP-Over-WDM Cross-Layer Design for Green Optical Networking With Energy Proportionality Consideration

Energy consumption in a network is becoming the physical limit against the everlasting increase of network traffic in the near future. Current network equipment consumes energy inefficiently due to poor energy-load proportionality of network equipment which causes a vast amount of energy consumption even in an idle state. We investigate and model the energy consumption of packet optical transport networks. Employing integer linear programming, we model and optimize the energy consumption of IP/WDM (IP/WDM) networks with traffic-grooming cross layer designs. Our study shows that energy savings in IP/WDM networks with traffic grooming is not effective unless IP layer equipment is energy proportional. In addition, different network planning schemes are required with respect to energy proportionality of network equipment.