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阐述网络地址转换的优缺点。

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正确答案:

答:(1)网络地址转换的优点在于:

①内部网络的主机可以通过该功能访问 Internet 资源,提供了解决 Internet 地址短缺的有效手段;

②为内部主机提供了部分“隐私” (Phvacy)保护。

(2)网络地址转换的缺点网络地址转换的缺点在于:

①由于需要对报文进行 IP 地址的转换, 涉及 IP 地址的数据报的报头不能被加密。 在应用层协议中,不能使用加密的 FTP连接,否则 FTP的 pod 命令不能被正确转换。

②网络调试变得更加困难。 比如,某内部主机试图攻击其它网络, 则很难指出究竟是哪一台机器是恶意的,因为主机的 IP 地址被屏蔽了。

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