IN THIS PAPER, WE PROVIDE A SERVICE BY MOVABLE SENSORS IN AD-HOC SENSOR NETWORKS WITHOUT ANY DISCONNECTING IN SERVICE.WE USE dominating set FOR THIS. A dominating set FOR GRAPH G IS A SUBset OF VERTICES SUCH THAT FOR ANY U Î V, EITHER U OR AT LEAST ONE NEIGHBOR OF U IS CONTAINED IN THE SUBset. DUE TO THE LIFETIME IN NODES, AND MOBILITY, THE NETWORKS TOPOLOGY CAN CHANGE OVER THE TIME, SO WE ARE LOOKING FOR SOME SITUATIONS THAT KEEP SERVICE IN THIS UNSAFE SITUATION. WE SHOW THAT IF THE NUMBER OF SERVERS BE AT LEAST [(N+1)/ 3], THEN BY REMOVING NODES FROM NETWORK WE CAN KEEP SERVICE IN WHOLE THE NETWORK WITHOUT ANY PROBLEM.