This paper focuses on region formation in Wireless This paper examines the problem ofgrouping wireless Sensor Networks (WSNs) as region formation plays an sensor nodes forming a network into a set of spatial important role in facilitating the programmability clusters. The technique for grouping the nodes [14,15], the scalability [10], collision reduction, and proposed here, exploits the spatial degradation in routing [1,18] in WSNs. Spatial aspects are also useful wireless signals to group the nodes into regions based in query processing [12], and for collaborative medium on the packet loss rate. The technique is validated on access control [13]. The term "spatial clustering" datasets obtained from actual wireless sensor denotes the formation of spatial regions that include a networks. The obtained results support the validity of set of neighboring sensors. Typically, a cluster consists the proposed approach. of sensors grouped according to a shared property. Shared properties can be a communication feature such 1. Introduction as the number of hops between any pair of sensors within the cluster [17], the actual distances separating sensors [13], or a sensing property like the correlation Forming spatial regions based on the communication between sensor readings [14]. characteristics of wired and wireless network nodes has several applications including localization of mobile Region formation based on physical distances has nodes [3], enhancing the scalability and QoS control several advantages as it allows controlling the size and [8], and supporting the use of region-based spatial shape of the regions. However, the physical location of logic to reason about networked systems [4].sensors is not always known. In many applications, sensors are randomly deployed and in others the sensor In general, a region is a contiguous finite extent of may drift under the effect of environmental factors like space surrounded by a boundary. Therefore, a region wind, rain, etc. Spatial clustering of sensors based on divides the space into three elements: a boundary, a communication properties allows us to form groups of finite internal space, and a possibly infinite external sensors that are physically close but does not ensure space. This conception of a region applies to one the size, shape, or even the continuity of the resulting dimensional, two dimensional, and three dimensional regions. However, there are advantages of this method spaces [7]. To apply this definition to network nodes, of clustering sensors. First, we can control the number the nodes must be grouped into localities according to of the resulting clusters. Moreover, we can some measurable quantity related to distance. For dynamically re-cluster the sensors as they drift or example, the distance can be represented by the hop move. Using sensing properties for clustering sensors count separating network nodes, or even better, the is highly dependent on the spatial properties of the Euclidean distances, if the location of each network physical phenomenon being se...