User's Manual

UTT Technologies Chapter 8 NAT
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Chapter 8 NAT
This chapter describes how to configure and use NAT features, including port forwarding,
DMZ hosts, NAT rule and UPnP.
8.1 Port Forwarding
This section describes the NAT > Port Forwarding page, which allows you to configure
port forwarding rules.
8.1.1 Introduction to Port Forwarding
By default, NAT is enabled on the Device, so the Device will block all the requests initiated
from outside users. In some cases, the outside users want to access the LAN internal
servers through the Device. To achieve this purpose, you need to create port forwarding
rules or DMZ hosts on the Device.
Using port forwarding, you can create the mapping between <external IP address:
external port> and <internal IP address: internal port>, then all the requests from outside
users to the specified external IP address: port on the Device will be forwarded to the
mapped local server, so the outside users can access the service offered by the local
server.
For example, if you want to allow the local SMTP server (IP address: 192.168.16.88) to be
available to the outside users, you can create a port forwarding rule: external IP address is
WAN1 IP address (200.200.201.88 in this example), external port is 2100, internal IP
address is 192.168.16.88, and internal port is 25. Then all the requests for SMTP from
outside users to 200.200.201.88:2100 will be forwarded to 192.168.16.88:25.