SDProber: A Software Defined Prober for SDN

Proactive measurement of the delay in communication networks aims to detect congestion as early as possible and find links on which the traffic flow is obstructed. There is, however, a tradeoff between detection time and cost (e.g., bandwidth utilization). Adaptive measurement adjusts the inspection rate per each link, for effective monitoring with reduced costs. In this paper we present SDProber---a tool for proactive measurement of delays in SDN. SDProber uses probe packets that are routed by adding tailored rules to the vSwitches. It adjusts the forwarding rules to route probe packets more frequently to areas where congestion tends to occur. To increase efficiency, SDProber uses a novel approach of probing by a random walk. Adaptation is achieved by changing the probabilities that govern the random walk. Our experimental results show that SDProber provides control over the probe rates per each link and that it reduces measurement costs in comparison to baseline methods that send probe packets via shortest paths.