An efficient multicast data forwarding scheme for mobile ad hoc networks

In order for multicast data packets to be transmitted efficiently, the multicast data forwarding is required at each router. Within a wired network, a network interface of a node has a one-to-one connection to one of the incoming interfaces of other nodes. If the packet coming into an incoming interface needs to be forwarded, it is delivered to the corresponding outgoing interface. However, in a mobile ad hoc network (MANET), in most cases each node has only one network interface, so the incoming interface is the same as the outgoing one and the wireless network interface of a node has a one-to-many connection to those of neighboring nodes. This difference may cause problems such as routing loops and packet duplication. Therefore, in this paper, we propose a multicast data forwarding scheme which can be used in the multi-hop wireless ad hoc network without causing either routing loops or packet duplication. In the proposed scheme, a table is defined for the prevention of packet duplication that can happen when the tree-based multicast routing protocol is used. We have implemented our proposed scheme by using the netfilter[1] of the Linux OS.