Abstract: “A wireless sensor network is a collection of nodes organized into a cooperative network. It comprising of spatially appropriated self-ruling mechanisms utilizing sensors to screen physical or ecological conditions. Now a day’s wireless sensor network is applied in many applications like military, nuclear power plant. In those applications data transmission rate should be in higher manner and the data transmission time should be very lower and all the nodes are in the cluster should be very secure also. For that single source shortest path algorithm – Dijkstra’s algorithm is used , from this algorithm the intermediate node between the sender and the sink node will be reduced and the data path will be reduced and the data transmission time will be reduced .If the node and the cluster is not secure the sensed data will be read by some of the intruder. For secure our cluster three tier security scheme is used. In this security scheme the node, cluster head, sink node are having their own k”

Keywords: MD5 hashing, Single source shortest path, Three tier security.