Mobile ad hoc network (MANET) is defined as a self-configuring infrastructureless network used for communication by wireless links with the support of mobile devices. A MANET is referred to as a wireless network with independent nodes moving freely with respect to each other. Due to the independent free moves of nodes, a huge amount of packet data loss occurs in transmitting the packet from source to destination. The risk of node misbehaviour is extremely high. The unsecured ad hoc network environment is initiated due to the active nature of networks and node mobility. In addition, the task of key management is more complex in ad hoc network. Due to the nature of free moving characteristics, MANET faces improper node cooperation. The main reason behind ineffective node cooperation is presence of malicious or selfish nodes. Moreover, the existence of malicious unauthenticated nodes causes insecure communication. Hence, the proposed system aims in the development of proper node cooperation, malicious node detection and secure communication in MANET.