We introduce a distributed algorithm for clock synchronization in sensor networks. Our algorithm assumes that nodes in the network only know their immediate neighborhoods and an upper bound on the network's diameter. Clock-synchronization messages are only sent as part of the communication, assumed reasonably frequent, that already takes place among nodes. The algorithm has the gradient property of [2], achieving an O(1) worst-case skew between the logical clocks of neighbors. As in the case of [3,8], the algorithm's actions are such that no constant lower bound exists on the rate at which logical clocks progress in time, and for this reason the lower bound of [2,5] that forbids constant skew between neighbors does not apply.
@article{arxiv.0704.3890,
title = {An algorithm for clock synchronization with the gradient property in sensor networks},
author = {Rodolfo M. Pussente and Valmir C. Barbosa},
journal= {arXiv preprint arXiv:0704.3890},
year = {2009}
}