Robustness to SYNC packets loss in network synchronization

Several factors may impact on the achievable performances of a synchronization system: among them, the accuracy of drift and offset estimates, the short and long term stability of the unregulated clock, the rate at which timing information are exchanged, the probability of losing protocol messages for a given period of time and so on. Therefore, when a synchronization scheme is considered, it is very important to also specify its robustness to possible malfunctions. In this paper the behaviour of synchronization mechanisms will be studied in correspondence to a synchronization loss. We shall analyse how clock instability and other factors, such as timestamp uncertainty and the particular implementation of a servo clock, may strongly affect the performances of a synchronization protocol. Finally, an accurate study based on the effect of measurement uncertainty will be reported to evaluate the robustness of a given synchronization mechanism with respect to an information loss.