Abstract: Mobile ad hoc networks are widely used and it is an important task to route efficiently. But traditional routing algorithms are not fit for mobile ad hoc networks due to their dynamic character and many routing algorithms of mobile ad hoc networks were proposed these years. Main classification standards for routing mechanisms were presented.Then basic routing protocols and routing algorithms for mobile ad hoc etwork were overviewed. After that, as the latest advance of routing algorithms, the prediction-based models, energy models, position-based models, QoS and security in routing algorithms were deeply researched. In prediction-based routing algorithms, using historical information, proper routes were rapidly chosen based on the prediction of nodes' motion. In energy-aware routing algorithms, the consumplion of energy was modeled based on the nodes' information. Then we introduced the special applications of the routing algorithms,including position-based routing algorithms,QoS routing algorithms and security routing algorithms. In position-based routing algorithms,forwarding decisions were made based on the geographical position of a packet's destination. hhe main idea of QoS routing algorithms was to take bandwidth, delay, energy and battery's life cycle into account while routing. In security routing algorithms, messages were encrypted based on secret keys, hash chains and electronic signatures. Last,more than thirty routing algorithms were compared and researched in the fields of computation overhead, communication overhead, storage overhead, optimal path, critical node and the types of the routing algorithms.The characters and applied areas of these routing algorithms were analyzed and the research trends in this field were proposed.

Key words: Ad hoc networks,Routing algorithms,Prediction routing,Energy-aware routing