Mobile Ad-hoc NETwork (MANET) has emerged as a new edge of technology to provide anywhere and anytime communication. Due to its deployment nature, MANETs are more susceptible to malicious attack. Due to the absence of centralized administration, security is the main issue in mobile ad-hoc network and attackers are very easily modified the actual behavior and performance of network. Security issues of MANETs in group (multi-cast) communications are even more challenging because of the involvement of multiple senders and multiple receivers.