Study Of QoS Guarantee In Ad Hoc Network

A mobile Ad hoc network (MANET) is a multi-hop, decentralized, self-configuring and peer-to-peer communication network that consists of several nodes with radio transceiver. It can be rapidly deployed and adapt to structured network without relying on the existing network infrastructure. Node in a MANET can join and leave the network independently without informing, which will not cause paralysis of the whole network.One main constraint in MANET is the limited power of the node. Therefore, much effort has been paid to reduce power consumption in network layer.Power control is one method. It aims at reducing energy consumption and interference in wireless communication, extending the lifetime of network by adjusting the transmission power of mobile nodes, without affecting the quality of communication. Ant Colony Algorithms is a novel algorithm for evolutionary simulation with characteristics such as optimization. Minimum power could be reached more rapidly by improving the ant-based power-control algorithm; number of calculation could be reduced according to current power, which better meets the requirements of MANET; reliability of transmission could be increased by adjusting the transmission power according to the length of message. After simulating, the result is compared comprehensively with those of other control algorithms. It can be said that the improved algorithms are an efficient and reliable protocol in wireless ad hoc networks.Otherwise, much research has paid attention to reducing energy consumption. A new power-aware routing mechanism based on Newton's interpolation is presented here. Firstly, life of a node is calculated according to the remaining energy of battery and the current traffic load of the node. Then the routing of minimum power-drain is selected from the nodes of longer life. In this way, the mechanism not only takes into consideration of the balance of the power at nodes, but also pays attention to the problem of minimum power-drain routing of the whole network. Simulations show that compared to previous algorithms, this mechanism has a better performance.