supervision istermed as mobile ad hoc network (MANET). It defines the set of wireless heterogeneousmobile nodes that performs communication with each other over multi-hop paths devoid of fixed infrastructure. The key aim of MANETs is to extent the mobility criteria inautonomous, mobile and wireless domain. The nodes in MANET perform as both hosts as wellas routers for sending the packet to each other. During ad hoc routing, every node in thenetwork is permitted to discover its multi-hop path via the network to any other node. Theapplication of the MANET includes military battlefields, emergency search, and rescuelocations etc which requires quick deployment and active re-configuration. Here the membersmake use of mobile devices for sharing the information. The process of broadcasting the packets to a group of zero or more hosts recognized bya single destination address is termed as multicasting. This implies that message istransmitted from one sender to several receivers or from multiple senders to multiple receivers.The merit of multicast technique is that it offers service to multiple users exclusive of networkand resources overloading in the server. The multicast technique is utilized by theapplication such as routing, neighbor discovery, key distribution and topology control. Thistechnique is also used in identical data transmission from a single sender to several receiversthat minimizes the network traffic and energy consumption. The multicasting approach can enhance the efficiency of the wireless links fortransmitting the multiple copies of messages in order to utilize the inbuilt broadcast nature of wireless transmission. Thus multicast takes a major responsibility in MANET. Themajor aim of multicast routing protocol is to reduce the control overhead and processingoverhead, enhancing the potentiality of multicast routing protocol, upholding the dynamictopology and avoids network loops and so on.
1.2 Security in multicasting in MANET The basic features of security in MANET are as follows: Confidentiality guarantees that thenetwork information cannot be revealed to the illegal unit. Integrity is essential to maintainthe data to be transmitted among nodes without any change or degradation. Availabilitymeans that the services are demanded are available in timely manner without anypotential issues in the system. The lack of authentication can cause the attackermasquerade any node and rules over the whole network. Non-repudiation guarantees thatthe message forwarded cannot be refused by the message instigator.
1.3 Key Management The methods of making, distributing and updating the keys for a secure groupcommunication application are termed as key management. Encryption and reencryption is completed with the assistance of Traffic Encryption Keys (TEKs) and KeyEncryption Keys (KEKs). In a secure multicast communication, each member possesses a keyto encode and decrypt the multicast data. The method of updating and distributing the keys tothe group members corresponds to re-keying operation. When each membership changes the re-key process is performed. However throughout continual membershipmodulation, key management needs several exchanges per unit time for upholding forwardand backward secrecies.