FastSplit: Fast and Dynamic IP Mobility Management in SDN

IP Mobility has many unresolved issues including triangle routing, session survivability, long delay and packet loss during hand-off. SDN-based IP Mobility promises to mitigate them by taking the advantage of network-wide visibility and centralized control. However, SDN-based approach still has some problems namely 1) large signaling overhead of controller and 2) high hand-off latency as the number of nodes and size of the network become large. This paper proposes a simple approach to efficiently handle IP mobility in SDN called “FastSplit”. FastSplit reduces the signaling overhead to reestablish the new path after movement by reusing the existing path between correspondent node (CN) and mobile node (MN). Our solution is two fold: 1) it finds out the redirection/split point in polynomial time by restricting the search area along the previous path between MN and CN, and 2)using Sub-Optimality Factor (SOF) for determining the cost-effective split point in order to manage the trade-off between the optimality of reestablished path and the reduction of signaling overhead for handling host mobility. We present an algorithm to find out a split point between MN and CN so that the existing path configuration can be reused. The evaluation results showed that FastSplit contributes to achieving significantly less signaling cost by reducing the number of SDN switches to reconfigure, by up to 50% as well as shortening the hand-off duration by 17% in comparison to OpenFlow based Mobile IP. FastSplit is also proven that such performance can be achieved without compromising the overall end-to-end throughput between CN and MN at the new location.