| Abstract |
Edge controller placement problem (ECP) aims at an optimal strategy toward minimizing traffic overheads and delays, which is a crucial concern when adopting Software Defined Networking (SDN) in-band control with multiple controller instances in edge networks. We demonstrate our solution to ECP, edge controller placement problem, which provides methods to place multiple SDN controller instances in an edge network, with minimum communication overhead or delay required. We address on following challenges. Firstly, a model describing and quantifying the communication overhead from and to SDN controllers is necessary. We establish such model by taking measurements of state-of-the-art SDN controllers. We particularly emphasize the overhead's dependence on the network scale, i.e. number of nodes and flows. Secondly, we notice that network delay has significant impact in the control plane of edge networks. We analyze it by conducting experiments using real mobile devices. Last but not the least, we model the controller placement problem in the context of minimizing overhead and delay costs as an integer programming problem and propose an algorithm to solve it efficiently. |