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A router that performs Network Address Translation (NAT) is installed between your computer and the Internet.The router fails. You connect the computer directly to the Internet.You need to ensure that the computer is connected to the Internet in the most secure manner possible.What should you do？（）

A.A

B.B

C.C

D.D

Server1 has two network connections. One network connection connects to the internal network. The other network connection connects to the Internet.All network connections connected to the internal network use private IP addresses. You install a Web server named Web1. Web1 hosts a secured Web site that only allows connections over TCP port 8281. Web1 is connected to the internal network.You need to ensure that the secure Web site can be accessed from the Internet.What should you do from the Routing and Remote Access console？（）

A. Configure Routing Information Protocol (RIP), and then activate authentication on the RIP interface.

B. Configure Routing Information Protocol (RIP), and then configure the incoming packet protocol settings on the RIP interface.

C. Configure Network Address Translation (NAT), and then add a new service to the NAT interface.

D. Configure Network Address Translation (NAT), and then enable the Secure Web Server (HTTPS) service on the NAT interface.

NAT(Network Address Translation)通过改变数据包的源(目的)(8)地址、源(目的)(9)来实现网络地址转换。 在Linux网关服务器中用iptables命令设置NAT规则。设Linux网关服务器有两个网卡，eth0接内网，eth1接外网。NAT服务配置命令如下：

(8)～(11)备选答案： A．POSTROUTING B． OUTPUT

C．PREROUTING D．IP

E．MAC F．端口号 G．192．168．1．0/24 H． 222．35．40．9/24

A. no NAT

B. destination NAT

C. source NAT

D. port address translation (PAT)

A．网络内部使用保留地址

B．所有的数据流量都要经过NAT网关才能发出

C．应用程序将经过地址转换过的包发给NAT，然后NAT再发出

D．内部地址需要和外部地址一一对应，才能实现地址转换