Distributed location service by using quorum methods for large scale wireless sensor networks

© 2010 by World Scientific Publishing Co. Pte. Ltd. All rights reserved. Location service provides position of mobile destination to source node, which is essential for geographic (or location assisted) routing algorithms in wireless sensor networks. This chapter first presents a brief review and analysis of traditional solutions on location service, where only local knowledge is required. The techniques reviewed include flooding based and hashing based schemes. Next, the chapter investigates the distributed location service which applies quorum methods. Basic quorum takes the row-column approaches so that the overhead of each routing task, including location service, can be controlled at, where n is the number of nodes in the networks. A connected dominating set can be established as backbone for quorum construction. As each location update and search works upon the backbone, the overhead can be further reduced. Moreover, if the quorum system adopts a hierarchical structure, both update and search operation can be restricted within the level as low as possible. We mainly focus on the representative research works that presented algorithms and approaches to create the quorum system for location service.