Architectural considerations and resource allocation in energy efficient networking

Abstract

Word-wide data traffic is continuously surging, triggered mainly by the emergence of Internet-of-Things (IoT)’s services and Fog-Cloud computing-based applications. This calls for existing optical and wireless-based network infrastructures to upgrade capacity accordingly to meet required massive bandwidth demands to accommodate the ever-surging data traffic volumes. However, continuously elevating the resource requirements in terms of bandwidth provisioning implies increasing the number of en-ergy-consuming network elements, which will increase overall operational expendi-tures and carbon footprint due to extra power generation. Carbon emissions contribute significantly to global warming. To avert this, it has become necessary to promote en-ergy-efficient networking. For that reason, it necessitated an emphasis on energy effi-ciency in the design, operation, and planning of transport networks. The current dense wavelength division multiplexing (DWDM) based optical transport network architectures operate with fixed-grid employing fixed data rates. So, making this rigid approach to capacity allocation leads to inefficiencies in both spectrum allo-cation and energy usage. Flexible (or elastic) optical transport networks with flexible-grid were proposed to improve bandwidth provisioning efficiencies. Such networks support adaptive line rates and OFDM-based optical transmission, thus, this will lead to lesser network elements deployed and, consequently an improvement in energy ef-ficiency. Similarly, wireless networks, whose data traffic is mostly derived from de-vice-to-device (D2D) communication and heterogeneous 5G cellular networks (HET-NETs) have since made tremendous strides to further enhance bandwidth by way of overlaying multiple types of low power small cells in a high-power macro cell. They afford more opportunities to explore the potential cognition and cooperation diversi-ties to improve spectral efficiency. Thus in this work, we focus on both architectural design and operation of wireless and optical transport networks coupled with resource allocation. A model joint all photonic and wireless transport network architecture framework is proposed and analyzed. The architecture’s performance in servicing high-capacity mobile back-haul and front-haul traffic and real-time services support is evaluated by both analytical and simulation approaches. Various routing and switching scenarios are considered. Overall, results demonstrate that elasticity allocation of resources (bandwidth) can vastly improve the network performance in terms of spectral efficiency, reduced locking probability, and enhanced end-to-end network throughput.