NATs cannot update upper-layer checksums.

NAT无法更新上层校验和。

UDP mappings in NATs are often deleted very quickly.

NAT 中的 UDP 映射通常会很快被删除。

This variation of NAT behavior a far, far worse problem than NATs themselves.

“这种变化的NAT行为是至目前为止, 到目前为止,更糟的问题比地址解析器自己”.

But a spokeswoman for Nats said: We certainly do not think we have overreacted.

但是国家空运局发言人说，我们完全不认为我们反应过度。

The outbound SYN packet from each host creates the necessary NAT state for its own NATs.

从各自的主机外出的SYN包，为他们自己的NAT产生可能的NAT状态。

This paper provides a method to create direct TCP connections between hosts behind different NATs.

文中给出了一种在两台位于不同NAT内的主机间建立TCP直连的方法.

Even so, NATs and firewalls have become a permanent part of the network infrastructure and will continue to remain so for a long time.

尽管如此，NAT和防火墙在网络下层构架中还是一个永远不可替代的部份，而且会在很长的时间内继续扮演下去。

Finally, our results can be used to guide the standardization process of NATs and firewalls, making them more traversal friendly without circumventing security policies.

最后，我们的结果能被用于引导标准化的NAT和防火墙程序的开发，使得它们不需要围绕严格的策略就能更加友好地穿越。

Understanding such behavior in NATs and measuring how much they detract from the original goal of universal connectivity in the Internet is crucial to integrating them cleanly into the architecture.

明白了NAT的行为，确认有多少在网络上的原始目的地连接，能很是清楚地把他们结合进框架中来。

The recipient uses the NAT-Discovery payloads to discover whether a NAT translated addresses or port numbers, and, based on which addresses and ports were changed, which peers are located behind NATs.

接收方使用NAT-Discovery有效载荷来发现NAT 之后是否存在一个经NAT转换过的地址或端口号，并基于被改变的地址和端口号来确定是否有对话方位于NAT之后。