© 2018 The Authors. Published by Elsevier Ltd. Black hole attack is one of the well-known attacks on Mobile Ad hoc Networks, MANET. This paper discusses this problem and proposes a new approach based on building a global reputation system that helps AODV protocol in selecting the best path to destination, when there is more than one possible route. The proposed protocol enhances the using of watchdogs in AODV by collecting the observations and broadcasting them to all nodes in the network using a low overhead approach. Moreover, the proposed protocol takes into account the detection challenge when a black hole continuously moves.