An Extension to the Precision Time Protocol (PTP) to Enable the Detection of Cyber Attacks

Abstract

The precision time protocol (PTP) is considered as one of the most favorable mechanisms for providing unified and precise time at the substation level in the smart grid. Nevertheless, PTP was shown to be vulnerable to cyber-attacks targeting its components and synchronization services. In this article, we capitalize on the theory and outcome of our previous work to contribute a more complete solution that addresses PTP cyber security. We propose to close the PTP loop through an extension that introduces new functionality and messages. This extension covers the PTP attack surface and enables the detection of attacks on PTP time synchronization. We formally model and verify the proposed extension using UPPAAL model checker. In addition, we validate the proposed extension using Omnet++ simulation. The evaluation demonstrates that our approach preserves PTP functionality, while successfully detecting cyber attacks against PTP components in a timely manner.