节点文献
基于UDP的端对端通讯的原理及实现
UDP based implementation of peer to peer communication
【摘要】 通过探索网络地址转换设备在进行UDP(UserDatagramProtocol)端口映射所存在的临时时间窗口,论述了使用UDP穿透网络地址转换设备的原理.引入检测及握手服务器及其所实现的数据包反射服务,来检测动态映射的端口信息以及网络地址转换设备在进行端口映射的特性.探讨了不同类型的网络地址转换设备对这种实现的影响,给出了检测过程以及建立端对端通讯过程的具体流程.这种实现可被广泛应用在IP语音、实时视频、文件共享以及分布式计算等应用中.
【Abstract】 By exploring the temporary UDP(user datagram protocol) port-mapping time window on NAT(network address translation) devices, the principal of using UDP to work through NAT devices was presented. A detection and handshaking server was proposed to solve the detection of dynamically mapped UDP ports. With packet reflecting service implemented at detection and handshaking server, port-mapping characteristics of NAT device and the external mapped UDP ports can be discovered. The procedures of the discovery process and the procedures of completing a peer to peer connection were presented. The implementation can benefit a broad range of applications like voice over IP, real-time video, file-sharing and peer to peer based distributed computing.
【Key words】 <Keyword>peer to peer; network address translation; firewall;