A Portable Time Synchronization Method using eBPF.

High-precision time synchronization between hosts connected via networks has become a necessity in recent years. That is used to measure delays between microservices, to reduce service response times, and is also used in IoT such as smart-phones. One of the methods for high-precision time synchronization is The Precision Time Protocol (PTP). PTP is a mainstream protocol that enables high-precision time synchronization, but the Linux implementation of the protocol requires a specific function on hardware or a driver to achieve high precision; thus, it is difficult to deploy to many devices including IoT devices. In this research, we propose a portable time synchronization method using the extended Berkeley Packet Filter (eBPF) for high-precision time synchronization. Our method is freed from specific hardware or driver functions and supports efficient conversion of timestamps used in the kernel-level and protocol-level. We compared the time-synchronization precision of the proposed method with that of the conventional methods, in which timestamps are provided by at hardware of network interface card (NIC) and NIC driver. The proposed method has equivalent precision to that using an NIC driver.