Semantic Routing Tree

The primary goal in here is to determine whether it needs to participate or not below child nodes in a given query over some constant attribute value. In generally says, an SRT is a distributed index to locate relevant nodes in the network. Usually, each node stores value interval of itself and its children also in the network. Therefore this will help for SRT to determine a particular node that is needed to participate or not in a given query. In this mechanism, it may be important task when making the selection for the parent node to implement the SRT routing tree algorithm. Traditionally, when doing the routing tree algorithm construction is done by having nodes pick a parent with the most reliable connection to the root in sensor networks. But in this case it is differ with respect to the SRT. Therefore, in making the selection the parent in an SRT is considered such that several parents of comparable link quality. This process is known as link-quality-based parent selection algorithm in the SRT. It will give more details about link-quality-based algorithm on [Woo A. and Culler D. July 2001].

In this case, theoretically the SRT can take as an index over constant attribute value of a sensor node. That is used to locate nodes that have relevant data with respect to the query. The important thing is in here that the SRT is an overlay on the network. This is because SRT keeps all indices of sensor nodes with regard to the constant attribute value. As well as each node in the network maintains a single one-dimensional interval showing the range with regard to the constant attribute values underneath every child nodes of the network tree. Usually, this will help to make efficient routing process throughout the network before particular query dissemination. The query processing task is proceeding in the network such that when a query q (as an example) with a predicate value say A (as an example) arrives at node n (as an example), then node n check whether if any child’s node attribute value of A overlaps the range of A attribute value in query q. If this happens, it receives result and forwards the query and also if it is not happened the query is not forwarded. As well as, if the query applies locally then node n begins to execute the query itself [Madden et al., 2003].