A Research Of Power-Saving Mechanism Based On Protecting Low-Remain Energy Nodes

Mobile Ad Hoc Network is a network without static infrastructure and energy-limited batteries host in most nodes in the network. Therefore, how to save power and increase longevity of the network is a crucial issue. Industrial circles have been trying to use power-saving mechanisms to increase the longevity of the batteries. At first in this paper, some typical power-saving mechanisms in Ad Hoc wireless network are introduced, classified and compared. Then, a new mechanism is proposed based on AODV protocol, which classifies the remaining power of the nodes into three levels, named normal level, warning level and dangerous level. Nodes under normal level will forward the packet without delay; Nodes under non-normal level will delay the Route Request Packet (RREQ) forwarding according to the delay model. Nodes under warning level will drop the non-RREQ packets with a low probability and nodes under dangerous level will drop the non-RREQ packets with a high probability. To reflect the real condition of Ad Hoc network more fairly and precisely, the paper forward a dynamic power-saving mechanism based on AODV protocol which gives attention to the power condition of neighbor nodes of current node. The purposes of these mechanisms are to protect the nodes which have low remaining energy, improve the efficiency of power and increase the longevity of the network. The mechanism is simulated on NS2. The simulation results show that the mechanism works well and achieve a good performance.