Research On Routing And Other Key Technologies In Peer-to-Peer Networks

With the rapid development of computer and communication technologies, users store more and more plenty of valuable content in there own computer, these results to the change of content storage center from the core of Internet to the access end user. Thus the model of Internet content transfer has been changed from C/S model to peer-to-peer model.Research on P2P technologies are the focus of network area and the hot topics of industry. General speaking, P2P means the overlay network above current Internet, each node in system are both the content provider and content consumer, and is responsible for the routing and delivery the messages coming from other nodes. Based on the difference of topology organization, P2P system can be classified to Un-Structured and Structured P2P system. This thesis focuses on Structured P2P system.Most structured P2P networks are based on distributed hash tables(DHT), for example, Chord, CAN, Pastry and Tapestry. Relied on the advantages in scalable and fault tolerance features of DHT technology, Structured P2P networks have been used widely in developing Internet scale network applications. But due to the shortcomings in early design, DHT systems suffer some problems including long routing latency, load unbalance and security issues when constructing semantic search. How to solve these problems is our concern in this thesis. As the same time, IPv6 protocol is widely deployed in the world, how to merge those two technologies is also our concern in this thesis. We have done some novel works in this thesis , including :Chapter 3 Proposes a novel method to extract topology information from IPv6 address prefixes. We notice that IPv6 addresses are assigned in a hierarchical way so that nodes with the same prefix are in the same autonomous domain. Therefore peers in a DHT system can learn their location information from their own IPv6 addresses. Devise a smart scheme to exploit the IPv6 address hierarchical feature, so as to construct an efficient version of Chord dubbed Chord6. We propose that node identifiers can be divided into several parts and thus be produced separately. For a node identifier divided into two parts, the higher bits can be obtained by hashing the shared address prefix among all nodes within the same AS, and the lower bits are the hash result of the rest of the IPv6 address. As a result, topologically close...