How to use Virtual IP config

Hello Everyone

if i need my exchange-OWA accessable from Outside i need to create a Virtual IP.

eg my public IP is 123.123.123.123 and my internal Exchange IP is 192.168.1.1

So i want that 123.123.123.123 Port 443 maps to 192.168.1.1 Port 443.

And here is my question:

As far as i can see i have to possibilities to reach my goal.

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Possibility 1) on VIP i configure

External IP Address/Range: 123.123.123.123

Mapped IP Address/Range: 192.168.1.1

On Port Forwarding i configure

External Service Port: 443

Map to Port: 443

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Possibility 2) on VIP i configure

External IP Address/Range: 123.123.123.123

Mapped IP Address/Range: 192.168.1.1

And under "Optional Filters" i configure a Service like "HTTPS".

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Both possibilities work.

Buth i guess there is something i don't understand?

Can you help me?

Best Regards,

Danfor