Hello and thanks for posting to our forum.
The most common way to do this would be to have a secondary block of public IP addresses from your provider available so you can do the 1:1 NATing. Typically you would have a /30 connection on the WAN side of the router to your provider as the primary IP on the WAN interface. For example:
eth 0/1 - Primary IP - 188.8.131.52 Mask 255.255.255.252 (with Default Route - 184.108.40.206 set)
eth 0/1 - Secondary IP - 220.127.116.11 Mask 255.255.255.240
eth -/2 - IP - 10.10.10.1 Mask 255.255.255.0
You could do 14 NATs with the 255.255.255.240 secondary block of Public IPs. If you were set on 15 you might need a /27 (255.255.255.224) block.
Here is a link to the NAT Pool Setup: Configuring NAT Pools in AOS
This guide provides all the commands needed for this application.
When we spoke on the phone your provider was not able to offer you this exact type of setup for your application. With their offering being limited, you would not have an easy way to set this up and test. However if you are able to receive this type of service, the NAT Pool setup would be perfect for your application.
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