Interval-based Clock Synchronization for Ad-Hoc Sensor Networks

Clock synchronization is a crucial basic service in typical sensor networks, since the observations of distributed sensors more often than not need to be ordered (“a happened before b”) or otherwise related (“a and b happened within a time window of size x”) in time. Ad-hoc sensor networks exhibit characteristics which make the use of traditional clock-synchronization algorithms infeasible. More appropriate algorithms have been presented recently. In this paper, we argue that interval-based synchronization is particularly suitable for ad-hoc sensor networks. Interval-based algorithms maintain lower and upper bounds on time instead of time estimates. We discuss the benefits of the intervalbased approach for ad-hoc sensor networks and present recent results.