Proactive Replication Scheme for Resilient Content Delivery in Software Defined Networks

Content delivery supported by Software defined network (SDN) controllers achieves high data extraction rate, granularity levels, content distribution and availability in the network. Proactive and dynamic content placement schemes at distributed servers facilitate content fetching ability that reduces the server replication cost and access delays in the network. In this regard, this article proposes a Proactive Replication scheme for Resilient Content Delivery (PRRCD) in SDN. The proposed model consists of the content origin server, proactive content replication servers, content providers, content flow and management controllers, internet service providers, gateway nodes and OpenFlow switches. The novelty approach of proposed model classifies the content objects based on client priority, event-driven contents and access rates, and resolve the sub-problems of content flow maximization. PCRS functions in controller-initiated (proactive push of content objects) and client-initiated modes (reactive pull of content objects). Integer linear programming with branch and bound approach eliminates the constraints of replication rate, cost and access delays, and defines the optimal bounded replication response. Simulation results indicate that the proposed model improves the content delivery rate and minimizes the replication cost and access delay in SDN as compared to the non-SDN based methods.