How to Configure One2One NAT Rule

Introduction
A business uses a UTT router to connect to the Internet through a static IP Internet connection, with multiple public IP addresses. It is required that all the employees' computers share a single public IP address to access the Internet, while the remaining public IP addresses are used for internal servers that users on the Internet can access.
 
Prerequisites
1. a UTT Business Router (hereinafter shorted as “the Router"), such as UTT router N518W, AC750W, AC750GW, AC1220GW, ER518, ER840G and ER4240G. Firmware Version: 3.0.0 or above
2. a PC/laptop connected to the Router wirelessly or through an Ethernet cable
 
Network Topology
In this example, the ISP provides five public IP addresses (from 218.123.123.2/29 to 218.123.123.6/29), which are assigned as follows:
UTT Router
WAN IP Address: 218.123.123.2/29
LAN IP Address: 192.168.1.1/24
Gateway IP Address: 218.123.123.1/29
Four Internal Servers
Real IP Addresses: 192.168.1.251/24 to 192.168.1.254/24
External IP Addresses: 218.123.123.3/29 to 218.123.123.6/29
 
Configuration
1. Go to Network > WAN, configure WAN1 with a static IP that internal hosts use to access the Internet, see the following figure.
 
2. Find NAT > NAT Rule at Network, click Add.
 
3. Select One2One from the NAT Type options, see the following figure. Select WAN1 from the Interface drop-down list and save the configuration.