EtherTime: Cross-Vendor Evaluation of PTP/NTP on Ethernet-Based COTS Embedded Platforms

We design and develop EtherTime, a tool for empirical evaluation of open-source implementations of the widely adopted Precision Time Protocol and Network Time Protocol standards. EtherTime is designed for distributed embedded systems networked over Ethernet. To demonstrate its benefits, we assemble a testbed of Raspberry Pi 4/5, Xilinx ZUBoard 1CG, and NVIDIA Jetson TK-1 boards, and carry out a measurement-based evaluation of four popular open-source implementations — PTPd, LinuxPTP, SPTP, and Chrony. EtherTime is successful in highlighting their limitations with regards to resource contention (specifically network and memory) and faults of various kinds (with/without hardware clock support). We open-source EtherTime and all datasets derived from this empirical study.