Optimised link state routing OLSR protocol is a popular proactive routing protocol for wireless ad-hoc networks WANETs. The functionality of OLSR protocol such as selection of multi-point relays, controlling the flooding of link state information and preparation of the routing table is depending upon the cooperation among the nodes in the network. However, open and decentralised network operations of WANETs introduce various security vulnerabilities to disrupt the routing process. To this end, this paper proposes a reputation-based trust model to enhance the cooperation among nodes in the routing process. The proposed trust model calculates the consolidate trust value CTV using direct and indirect observations. This CTV is used in the OLSR process to identify and isolate the misbehaving nodes from the routing path without having additional overhead. The simulation results show the effectiveness of the proposed method.