Issue No. 04 - April (2011 vol. 22)
DOI Bookmark: http://doi.ieeecomputersociety.org/10.1109/TPDS.2010.102
ShiGuang Wang , Illinois Institute of Technology, Chicago
XuFei Mao , Illinois Institute of Technology, Chicago
Shao-Jie Tang , Illinois Institute of Technology, Chicago
Xiang-Yang Li , Illinois Institute of Technology, Chicago
JiZhong Zhao , Xi'an Jiaotong University, Xi'an
GuoJun Dai , Hangzhou Dianzi University, Hangzhou
In wireless sensor and actor networks (WSANs), a set of static sensor nodes and a set of (mobile) actor nodes form a network that performs distributed sensing and actuation tasks. In , Abbasi et al. presented DARA, a Distributed Actor Recovery Algorithm, which restores the connectivity of the interactor network by efficiently relocating some mobile actors when failure of an actor happens. To restore 1 and 2-connectivity of the network, two algorithms are developed in . Their basic idea is to find the smallest set of actors that needs to be repositioned to restore the required level of connectivity, with the objective to minimize the movement overhead of relocation. Here, we show that the algorithms proposed in  will not work smoothly in all scenarios as claimed and give counterexamples for some algorithms and theorems proposed in . We then present a general actor relocation problem and propose methods that will work correctly for several subsets of the problems. Specifically, our method does result in an optimum movement strategy with minimum movement overhead for the problems studied in .
Connectivity restoration, controlled node mobility, fault tolerance, wireless sensor and actor networks.
S. Wang, X. Li, J. Zhao, S. Tang, G. Dai and X. Mao, "On “Movement-Assisted Connectivity Restoration in Wireless Sensor and Actor Networks”," in IEEE Transactions on Parallel & Distributed Systems, vol. 22, no. , pp. 687-694, 2010.