Multi-domain integrated grooming algorithm for green IP over WDM network

With the continuous expansion in the network scale and growing popular Internet applications, the sharply increasing electrical consumption and even carbon dioxide emissions have became bottlenecks of the future network development. Consequently, greening network comes to a very important issue. Foremost, ensuring the scalability and robustness, we divide the network into multiple domains for the distributed routing and management. As these tendencies undergo widespread attentions, providing solutions for multi-domain green networks are of the utmost importance. This paper enables the power conservation in multi-domain IP over WDM networks by means of presenting a power- and port-cost- efficient approach. This approach delves into power-efficient channel provisions of connection demands and an effective integration of the hybrid grooming and the waveband merging. For each intra-domain connection demand, our method executes the intra-domain hybrid grooming within the physical topology and updates the power efficiency of this domain in real-time. For each inter-domain connection demand, through link-cost adjustments, our method first computes the loose route which is the most power-efficient path from the source border node to the destination border node within the logical topology. The link-cost adjustment aims to make the loose route traverse over higher power-efficient domains and logical links. Next, it orderly performs the intra-domain hybrid grooming between two selected border nodes in each traversed domain of this loose route, from the source node to the selected border node in the source domain and from the selected border node to the destination node in the destination domain. In final, within each single domain, our method merges several full-loaded lightpath segments into a single waveband tunnel along with more than two physical hops by the intra-domain waveband merging. The Optical Cross-Connect (OXC) ports are able to be further saved. In comparison to the traditional multi-domain grooming approach, our method exhibits the higher power efficiency and port savings.