可靠P2P文件传输算法的研究与实现

Study and Implementation of P2P Reliable File Transmission Algorithm

P2P技术通过改变经服务器中转交换文件的传统方式,达到自由交换资源的目的。为解决网络地址转换(NAT)技术在解决公网IP紧缺,确保网络安全而起到重要作用的同时,阻隔了不同子网内用户间直接通信的问题,介绍了一种能够在两个NAT设备主机间建立直接TCP连接的方法,称为Nat Trav。仿真结果达到了预期效果,试验成功。

Peer-to-Peer （P2P） networks have become increasingly popular. Controversy generated by P2P file-sharing programs and other 1.seful and legitimate application of P2P exist. Network Address Translation is introduced as a means to continue the Internet＇s growth despite rapid depletion of IPv4＇s 32-bit address range. A secondary function of NAT is to hide the network topology from an external entity, while NAT causes well-known difficulties for peer-to-peer communication. This paper proposes approach called NatTrav to create TCP connection between two hosts behind typical NATs designed for small networks. It is implemented successfully in simulation environment.