Research On Virtual Force Based Cooperative Broadcasting Algorithm In Mobile Ad Hoc Networks

Broadcasting is one of the key technologies necessary in mobile Ad Hoc networks.The simplest way of broadcasting is flooding.But blind flooding causes information redundancy,channel contentions and package collisions,which will lead to broadcasting storms and broadcasting unreliability,seriously affecting the broadcasting performance.In addition,nodes in mobile Ad Hoc networks are typically battery-powered and they have very limited energy.Thus,energy consumption is also a key factor that affects the network lifetime.Therefore,the research on effective broadcasting mechanisms is crucial for network communication.To mitigate the broadcasting storm,prolong the network life-time and provide the broadcasting reliability,a virtual force based cooperative broadcasting algorithm(VFCB)is proposed.In VFCB,each node ready to send a broadcast packet takes itself as the center and divides its surrounding area into five sectors based on the direction of the virtual force between itself and the previous hop node.Except the sector where the previous hop node is located(Since the nodes in this sector are basically covered by the previous transmission,the next hop forwarding node is no longer selected from this sector),the node with the largest virtual force is selected from the remaining four sectors as the next hop forwarding nodes.So the maximum number of the next hop forwarding nodes is up to four.Then the four forwarding node addresses are encapsulated in the header of the packet ready to be sent.A neighbor node receives the broadcast packet will determine whether the packet needs to be forwarded according to the forwarding node address list in the broadcast packet header.If yes,repeat the above node selection and forwarding process.In VFCB,because fewer forwarding nodes are selected and the selected forwarding nodes are not concentrated in the same direction area,which effectively avoides the information redundancy and channel competitions that are referred to as the broadcasting storm,reduces the energy consumption of the nodes and prolongs the network life-time,provides reliability to some extent.Meanwhile,the value of virtual force is calculated according to the successful broadcasting ratio and the residual energy of neighbor nodes.The nodes with the higher successful broadcasting ratio and/or higher residual energy are more likely to be selected as the forwarding nodes.As a result,mitigating the broadcasting storm,improving the broadcasting reliability,balancing the node energy consumption and prolonging the network life-time.The simulation results show that the VFCB algorithm has lower forwarding nodes ratio,longer network lifetime and shorter end-to-end delay and comparatively low reachability,which demonstrates that VFCB algorithm has a better performance regarding the broadcast storm mitigating,network lifetime prolonging.Meanwhile,it can still provide reliablility to some extent.So VFCB can efficiently adapt to the mobile Ad Hoc networks well.