Hi,
Suppose your internal Server IP address is 192.168.1.10 and you have a public IP from the ISP, suppose 9.9.9.9.
You want to host various applications on the internal server working on different ports, and want them accessible from the internet.
You create a static NAT between 192.168.1.10 and 9.9.9.9. This essentially means that all ports on 9.9.9.9 are translated to all ports on 192.168.1.10.
However, currently you have only one single port on the internal server which is running an application. Hence, you create a security policy to allow just that one port from the Internet Zone to the Server Zone and thus blocking access to all the other ports on that IP despite of having a NAT for all the ports.
Please let me know if the explanation is clear.
Regards,
Sahil Sharma
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