Mobile ad hoc networks (MANET) have some unique characteristics like infrastructure-less, hop by hop communication, and dynamic nature. Routing in MANET is very challenging because there are frequent route breaks due to node movements. To avoid the route request (RREQ) packet flooding storm during the route estimation phase, the Adaptive request Zone-Based Optimal Selective Forwarding with location (AZBOSF) routing protocol uses two zones namely request and expected. The RREQ packet is flooded in the request zone area, that determined by the source node during the route estimation phase. The expected zone is that area where the source node is expecting the availability of the destination node. This AZBOSF routing protocol adapts the request zone and expected zone dynamically with respect to length among the source and the destination node for achieving better performance. However, during the communication phase in the original protocol security mechanism is not considered. Being a wireless network, MANETs are susceptible to many attacks. The MANETs are generally application-specific, and if the application is like military, then security issue is very important.  Hence for maintaining the secrecy and integrity of the data and to achieve the goal of trusted communication in this routing protocol, proposed a security mechanism using trust and identity with key management.