Abstract
Software-Defined Networking (SDN) is a virtualised yet promising technology that is gaining attention from both academia and industry. On the one hand, the use of a centralised SDN controller provides dynamic configuration and management in an efficient manner; but on the other hand, it raises several concerns mainly related to scalability and availability. Unfortunately, a centralised SDN controller may be a Single Point Of Failure (SPOF), thus making SDN architectures vulnerable to Distributed Denial of Service (DDoS) attacks. In this paper, we design SMART, a scalable SDN architecture that aims at reducing the risk imposed by the centralised aspects in typical SDN deployments. SMART supports a decentralised control plane where the coordination between switches and controllers is provided using Tuple Spaces. SMART ensures a dynamic mapping between SDN switches and controllers without any need to execute complex migration techniques required in typical load balancing approaches.