title: Clock synchronization in wireless sensor networks: an overview.
abstract: The development of tiny, low-cost, low-power and multifunctional sensor nodes equipped with sensing, data processing, and communicating components, have been made possible by the recent advances in micro-electro-mechanical systems (MEMS) technology. Wireless sensor networks (WSNs) assume a collection of such tiny sensing devices connected wirelessly and which are used to observe and monitor a variety of phenomena in the real physical world. Many applications based on these WSNs assume local clocks at each sensor node that need to be synchronized to a common notion of time. This paper reviews the existing clock synchronization protocols for WSNs and the methods of estimating clock offset and clock skew in the most representative clock synchronization protocols for WSNs.
authors.affiliation: Department of Electronic Engineering, Hannam University / 133 Ojung-Dong, Daeduck-Gu, Daejun, 306-791, Korea; E-Mail:  ikrhee@hnu.kr.
authors.forename: Ill-Keun
authors.initials: IK
authors.lastname: Rhee
authors.forename: Jaehan
authors.initials: J
authors.lastname: Lee
authors.forename: Jangsub
authors.initials: J
authors.lastname: Kim
authors.forename: Erchin
authors.initials: E
authors.lastname: Serpedin
authors.forename: Yik-Chung
authors.initials: YC
authors.lastname: Wu