Exploring Blockchain-driven security in SDN-based IoT networks

The Internet of Things (IoT) is an emerging field of technology with a huge scope of its applicability in various industries and a wide range of societal needs, including medical sciences. However, IoT suffers from many limitations like energy, resource constraints, scalability, security, availability, etc. Software-Defined Networking (SDN) is another similar technology that has many features that are capable of solving many of the limitations of the conventional IoT system. So, suitably incorporating SDN technology into the conventional IoT system, an improved version of IoT namely an SDN-based IoT network system has been evolved. This system is capable of resolving many of the limitations of IoT. Since this newer SDN-based IoT version is enriched with better energy and resources, it can undertake higher computational loads to resolve security issues. In the security domain, Blockchain is a state-of-the-art security-based technology in recent times which has already been implemented in the fields of cryptocurrency effectively. So, Many research opportunities emerge out in adapting Blockchainbased technology suitable for the SDN-based IoT Networking domain. This paper deals with the investigations carried out by the past researchers on various security aspects of the IoT, SDN, and SDN-based IoT systems and their solutions using various technologies, including that of Blockchain. It was concluded that the convergence of Blockchain in IoT and SDN and its combination (SDN-based IoT) resolved many security issues. Many prominent research gaps still persist here to be resolved. This can be dealt with as a future scope of research opportunities in the domain.