Wireless Sensor and Actuator Networks: Algorithms and Protocols for Scalable Coordination and Data Communication

8.5 QUORUM-BASED ALGORITHMS

Quorum-based location service has been widely used in fixed networks and cellular networks (Prakash and Singhal, 1996; Prakash et al., 1997; Krishnamurthy et al., 1998). Its adaptation for wireless ad hoc networks is suggested in Stojmenovic (1999), Liu et al. (2006), and Stojmenovic et al. (2008). So far, several different variants (e.g., Abraham et al., 2004; Li et al., 2008; Liu et al., 2009) of the quorum technique have been proposed for location service. In this section, we review these existing work in detail.

8.5.1 Strip Quorum

Stojmenovic (1999), Liu et al. (2006), and Stojmenovic et al. (2008) proposed a localized strip quorum technique for wireless ad hoc networks with connectivity-based location update policy. Each actuator monitors the state of its incident links. Whenever a link breakage/creation occurs (possibly due to its own movement), it reports its current position to its neighbors. After a certain number of link changes, it forwards its current position to all the nodes located in a “column.” That is, it sends its location in both north and south direction to reach the north and south boundaries through GFG routing protocol (Bose et al., 1999). The nodes along this column form an update quorum. Note that GFG will route the location update message along the outer boundary of the network, which is thus included in the update quorum.

A source sensor queries its q-hop neighborhood for target actuator's location. If the answer is negative, ...