Multi-class routing protocol using virtualization and SDN-enabled architecture for smart grid

Routing Protocol for Low Power and Lossy Network (RPL) is standardized and known as the primary solution for the last mile communication network in the smart grid. Various applications with different requirements are rapidly developed in the smart grid. The need to provide Quality of Service (QoS) for such a communication network is inevitable. In this paper, we use the benefits of virtualization and software-defined networking to present a virtual version of the RPL protocol which we name OMC-RPL (Optimized Multi-Class RPL). We present an SDN-enabled architecture consisting of a central controller and some SDN nodes. This implementation reduces the complexity and controls interactions to distribute the network states and other related information in the network. The proposed SDN-enabled architecture consists of different components including Network Link Discovery, Topology Manager, and Virtual Routing. OMC-RPL utilizes a holistic objective function including distinctive metrics related to QoS, and supports the data classification which is an essential requirement in this context. The proposed objective function considers different numbers of traffic classes by using weighting parameters. An optimization algorithm determines the best values of these coefficients. OMC-RPL is evaluated in different aspects. Simulation results show that the new idea significantly decreases both the end-to-end delay and packet loss which are the important factors of QoS. The virtualization idea is also investigated, which results in less message exchange.