The anonymity and inaccessibility of the internal hosts behind a middlebox is not a problem for client software such as web browsers, which only need to initiate outgoing connections.

• 这样的话，这些匿名的并且看起来难以触及的藏在NAT之后的内网主机对于像Web浏览器这种软件来说就不是一个问题,因为内网的主机只需要发起向外部的连接就可以了。