Research And Design Of NAT Travsering Scheme Based On Hybrid P2P Network Under UDP

With the rapid development of the application based on P2P network technology, P2P has brought the users tremendous convenience and efficiency, and it makes full use of the network resource, greatly increasing the bandwidth utilization. NAT technology handicaps the further P2P application, although it is widely used to solve the problem caused by public IP addresses lackness. NAT traversing based on P2P has become a hotspot of P2P application. Nowadays, the special construction characteristic is used to implement P2P communication by utilizing skype experience and improving the NAT traversing scheme of super nodes under UDP. With the help of information recorded by super node, dissymmetry NAT traversing can be implemented by P2P applications, symmetry NAT traversing under P2P can be resolved by the relay of super nodes, and P2P communication can be archieved finally. For the particularing of theIn order to complete the program design and implementation of work, this paper include the following:Detailed concept of the NAT, NAT functions, the current commonly used type of NAT technology, specific NAT works, the current popular P2P network application as well as P2P technology are studied. The NAT technology bringing P2P applications with the traversing problems is deeply analyzed..The various NAT traversal solutions are detailedly studied , and various programs of the performance, the deployment of occasions, feasibility and scalability are analyzed and summaried; and the hybrid P2P network structure are deeply researched and analyzed, and the super-node, the operation of the principle and implementation process are introduced. For the particularity of the hybrid P2P network structure, the program of the expandable design of super-node functionality of the program NAT is introduced ,the STUN detection module and the TURN relay module are increased, and the establishment of user information record is designed, and at last the design process of the NAT is detailedly introduced and analyzed.To the super-node system the paper makes a framework design and specific module design, including STUN type checking module, TURN relay module of code design and flow chart of the design.The scheme raised in this paper is varified, and it`s correctness and availability are demostrated by the analysis of the experiment results.Finally this paper summarizes the advantages and disadvantages of the program and proposes a further improve the research content.