TCP穿透NAT技术.doc

原文: -tcpnat/ 译者:云中哈哈翻译开始时间: Abstract: 概要 In recent years, the munity has developed techniques for traversing NAT/fi rewall boxes with UDP (that is, establishing UDP flows between hosts behind NATs). Be cause of the asymmetric nature of TCP connection establishment, however, NAT traversa lof TCP is more difficult. Researchers have recently proposed a variety of promising app roaches for TCP NAT traversal. The ess of these approaches, however, depend onho w NAT boxes respond to various sequences of TCP (and ICMP) packets. 近几年,标准化连接已经发展了用 UDP 穿透 NAT 和防火墙的技术,那就是,在主机和 NAT 间建立 UDP 流。因为 TCP 连接建立的不对称性,所以 TCP 穿透 NA T 是比较困难的。近期,研究者们通过大量的渠道去尝试 TCP 穿透 NAT ,依赖于 NAT 回复的大量 TCP 和 ICMP 包的顺序,终于有方法得以成功打通 NAT 。 This paper presents the first broad study of NAT behavior for prehensive set of TC P NAT traversal techniques over a wide range mercial NAT products. We develop eda publicly available software test suite that measures the NAT's responses both toa var iety of isolated probes and plete TCP connection establishments. We test sixteen N AT products in the lab, and 93 home NATs in the wild. Using these results, as well as ma rket data for NAT products, we estimate the likelihood of essful NAT traversal for h works. The insights gained from this paper can be used to guide both design ofT CP NAT traversal protocols and the standardization of NAT/fir