How to measure the speed of light with programmable data plane hardware?

Abstract

Driven by real-time applications such as IIoT, TSN and vehicular networks, the optimization of networks and its elements regarding latency and throughput becomes more and more important. With this demo we show how latencies of network components can be identified within nanosecond accuracy by use of commodity P4 hardware. We show a measured propagation speed of $5ns/m$ in fiber optical cables. Besides that, our approach scales up to $100Gbit/s$ link speed by the aggregation of many low-cost load generators to a flexible software-based load generation.