In-Band Locating High Delay Variance Links with Programmable Data Plane

The variation in packet delays, whether occurring on a link or across an end-to-end path, can be precisely quantified as a statistical metric, indicative of the extent of fluctuations in packet delay. Links exhibiting high packet delay variance often signal congestion or instability, making it imperative to identify and monitor such links for effective network performance management. In a prior study, we introduced a method for pinpointing high packet-delay variance links within OpenFlow networks through the use of multicast measurement packets, routed strategically, and by gathering flow statistics of these probe packets from selected OpenFlow switches (OFSs). However, this approach relied passively on the controller-triggered transmission of OpenFlow Flow-Stat packets, leading to delayed detection and response to network events. To address this limitation, our paper proposes a novel scheme leveraging programmable data plane-enabled switches, such as P4-enabled switches, to actively compute packet delay variance and notify the urgent information to the controller. Simulation results demonstrate the effectiveness of our proposed scheme in achieving accurate estimation and rapid response to changes in network conditions.