Sharing a common time reference in a heterogeneous distributed system

This article introduces SYD, a tool for the generation of time-stamps synchronized with the Universal Time Coordinate: the implementation includes an NTP client and is written in Java. Possible applications include (but are not limited to) the measurement of the performance of distributed applications, their debugging, and the implementation of real-time requirements in distributed systems. The features that characterize SYD are its portability across platforms, the low cost in terms of network overhead, and the absence of interference with other applications running on the same host (SYD does not synchronize the system clock!). In this paper, we prove that the choice of Java does impact on the performance of the tool, when compared with an equivalent application written in C. SYD is available on the Web as public domain software