112 Int. J. Communication Networks and Distributed Systems, Vol. 2, No. 1, 2009 ‘Ripples’: message-efficient, coverage-aware clustering in wireless sensor and actor networks Neeta Trivedi* Aeronautical Development Establishment, DRDO, Bangalore-560075, India E-mail: neeta@ade.ernet.in *Corresponding author S. Sitharama Iyengar Department of Computer Science, Robotics Research Laboratory, Louisiana State University, Baton Rouge, LA-70802, USA E-mail: iyengar@bit.csc.lsu.edu N. Balakrishnan Supercomputer Education and Research Centre (SERC), Indian Institute of Science (IISc), Bangalore-560012, India E-mail: balki@serc.iisc.ernet.in Abstract: We propose ‘ripples’, a lightweight scalable algorithm for self-organisation and self-healing in wireless sensor and actor networks (WSAN). The novelty of the algorithm lies in its unified approach to deterministically address the multitude of challenges present in WSAN with extremely low communication and computation overheads, optimally exploiting the redundant deployment. ‘Ripples’ also facilitates design of efficient data dissemination algorithms and networking protocols for routing with guaranteed delays. A sub-module ‘bind’ has been outlined that associates the clusters to their nearest actor nodes; this is required for real-time response. ‘Bind’ works along with ‘ripples’ and creates route and data tables that can be used by the data dissemination algorithm and networking protocols for efficient operation. Keywords: wireless sensor and actor network; WSAN; resource-efficient; geography aware; sensing coverage aware; self organisation; self-healing. Reference to this paper should be made as follows: Trivedi, N., Iyengar, S.S. and Balakrishnan, N. (2009) ‘‘Ripples’: message-efficient, coverage-aware clustering in wireless sensor and actor networks’, Int. J. Communication Networks and Distributed Systems, Vol. 2, No. 1, pp.112–134. Biographical notes: Neeta Trivedi is a Research student at IISc, Bangalore, India. She received her MSc (Engg) from IISc. She has worked in the areas of embedded real-time systems, computer graphics, computer networking and sensor networks. Copyright © 2009 Inderscience Enterprises Ltd.