Feasible Time Delay Attacks Against the Precision Time Protocol

Time synchronization in packet-switched networks has evolved into an indispensable prerequisite for many modern applications. In addition to high accuracy demands, also reliability and security are evermore of great concern. Despite the proposal of supplementary security concepts in the past years such as the four prongs in Annex P of the IEEE 1588 standard, available protocols are still vulnerable to time delay attacks. In this paper, we propose multiple methods to implement realistic delay attacks and verify the feasibility on a hardware testbed. Furthermore, we perform a risk analysis to evaluate the actual threat of delay attacks in practical applications. Our analysis shows that time delay attacks still pose a great threat to current systems and further research is required to find sound countermeasures.