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Chapter 4
4.4 NAT Forwarding
The router’s NAT (Network Address Translation) feature makes the devices on the
LAN use the same public IP address to communicate on the internet, which protects
the local network by hiding IP addresses of the devices. However, it also brings
about the problem that external hosts cannot initiatively communicate with the
specied devices in the local network.
With the forwarding feature, the router can traverse the isolation of NAT so that
clients on the internet can reach devices on the LAN and realize some specic
functions.
The Mercusys router includes four forwarding rules. If two or more rules are set, the
priority of implementation from high to low is Port Forwarding, Port Triggering, UPNP
and DMZ.
4. 4. 1 Port Forwarding
When you build up a server in the local network and want to share it on the internet,
Port Forwarding can realize the service and provide it to internet users. At the same
time Port Forwarding can keep the local network safe as other services are still
invisible from the internet.
Port Forwarding can be used to set up public services in your local network, such
as HTTP, FTP, DNS, POP3/SMTP and Telnet. Dierent service uses dierent service
port. Port 80 is used in HTTP service, port 21 in FTP service, port 25 in SMTP
service and port 110 in POP3 service. Please verify the service port number before
the conguration.
I want to:
Share my personal website I’ve built in local network with my friends through the
internet.
For example, the personal website has been built in my home PC (192.168.1.100).
I hope that my friends on the internet can visit my website in some way. My PC is
connected to the router with the WAN IP address 218.18.232.154.