Power efficient grooming based on optical bypass reconfiguration in green optical networks

With the growing greenhouse effect and energy crisis, energy saving has become the focus of global concern. From the perspective of networks, greening the network for building an energy-efficient network has been presented in recent years. However, in previous works, once a lightpath is established, it cannot be changed until it is released due to its holding time expiration, even though this lightpath may not be reasonably configured to current traffic. To overcome the shortcoming of previous works, this paper considers the optical bypass reconfiguration for existing lightpaths, and proposes a new power-efficient grooming algorithm (PEGA) based on the improved grooming graph model (IGGM) to reduce the average energy consumption for each demand. PEGA takes into account the energy consumptions of various components, such as core routers, transceivers, optical amplifiers, and so on. By using the optical bypass reconfiguration method based on the bypass-cascading conversion link (BCCL) in IGGM, PEGA can properly split an existing lightpath into two new lightpaths to achieve better resource utilization. Simulation results show that, compared to previous algorithm, PEGA can effectively reduce both the average energy consumption for each demand (AEED) and the blocking rate (BR). (C) 2012 Elsevier GmbH. All rights reserved.