Topology-Aware Overlay Network Based On RAQ

At Present , Peer-to-Peer (P2P) is a research hotspot in distribution computing network.Structured P2P system based on distributed hash table like Chord,CAN,Pastry and Tapestry,can achieve a query length of O(logN) with using O(logN) neighbors per node. Now, many overlay networks are made of P2P systems, but the topology structure of physical network is not consided, and it has tremendous network delay in the process of routing. So,how to resolve the mismatching problem between overlay and physical network becomes a hotspot in P2P research.In order to resolve the topology-aware problem,the methods generating proximity information and exploiting proximity information were proposed, This dissertation presents a multi-dimensional overlay network called T-RAQ which is based on RAQ.RAQ supports exact match queries and range queries over multi-dimentional data efficiently. Moreover, its routing cost does not depend on the dimention of the search space. In T-RAQ, we have improved its original routing algorithms and extended it to have topology awareness property. A topology match between the overlay and underlying network results in reduced routing delay and network link traffic. In order to provide the topology awareness, the different node-join algorithms and routing table maintenance is presented in comparison with RAQ. and the improvement on existing P2P systems had achieved effective routing mechanism.At last, the experiment results show that topology aware properties can be achieved with low overhead in network topologies. Additionally, simulations on GT-ITM show that these properties can hold in realistic network topologies. The results also show that considering topology awareness can provide a significant performance improvement relative to topology unaware routing.