MANET Attack Prevention - Recently, the rising use of portable devices with advanced wireless communication gives Mobile ad-hoc networks more significance with the expanding number of widespread applications. This infrastructure uses a link-to-link wireless connection to transfer the data called route, which uses a routing protocol. AODV is a reactive protocol that uses control packets to discover a route toward the destination node in the network. Since MANET is an open infrastructure without a centralized controller, it is at risk of security assaults that are generated through the malicious node at the time of route discovery and data transmission. For example, the Blackhole attack in which the offender node retains and drops few or all data/control packets by using vulnerabilities of the on-demand routing protocols. This paper proposed a trust-based method to prevent the network against blackhole attack. This paper modeled the behavior of blackhole node and proposes a trust-based security technique. Further suggested technique is analyzed and evaluated against various evaluation metrics like PDR, throughput, end-to-end delay, attack percentage, etc. The proposed security technique is also compared with three different scenarios, namely attack, watchdog, and IDS scenarios, using the above evaluation metrics. The comparison shows that the proposed trust-based security ensures the detection and prevention against blackhole nodes not only at the time of route discovery but also at the time of real-time data transmission.