Trust Based Hierarchical Key Management Scheme for Secure Group Communication in mobile Ad hoc networks
Priyadharshini Annadurai, Vadivel Palanisamy · 2008
ad hoc network (MANET) is a kind of wireless communication infrastructure that does not have base stations or routers. Each node acts as a router and is responsible for dynamically discovering other nodes it can directly communicate with. However, when a message without encryption is sent out through a general tunnel, it may be maliciously attacked. The main idea in our proposal is key management for secure group communications in MANETs with two-layer structure. The level 1 subgroup (L1-subgroup) contains all of nodes in the subgroup. The level 2 subgroup (L2-subgroup) can be decided according to the location information of nodes in the L1-subgroup. Our scheme is to create a cluster head that manages information, and constructs and transmits the group key. First, in each subgroup, we select a node with the largest weight value to be the level 1 cluster head (L1-head) in each L1-subgroup. Then, in each L2- subgroup, the node with the largest weight value will be the level 2 cluster head (L2-head) and manage the other nodes of the L2- subgroup. With help of the cluster heads, the nodes authenticate each other and exchange their public key in a secure manner. The cluster head selection is based on the degree of node (i.e number of neighbors around the node) and node's identification number. Apart from these parameters, the member nodes asses trust of the cluster head. In this paper, we propose a trust based hierarchical key management scheme (TBHKMS) for secure group communications in MANETs. For the sake of security, we encrypt a packet twice. Due to the frequent changes of the topology of a MANET.