Differences and usage of the NAT mode, routing mode, and full mode of ER Series Routers

The ER series routers are available in three modes: NAT mode, route mode, and full mode. The differences and applications of the three modes are as follows:

 

NATMode

In NAT mode, when the DMZ port is in Wan mode or LAN mode, the mode relationships between interfaces are also different.

1DMZ port is in Lan mode

The LAN and WAN are in NAT mode, and the DMZ and WAN are also in NAT mode. That is, the IP address of the LAN or DMZ is converted to the IP address of the WAN port after passing through the WAN port. The routing mode is used between the LAN and DMZ.

It is mainly used in scenarios where multiple LAN computers share the Internet through a single broadband.

2The DMZ port is in Wan mode.

In Wan mode, the DMZ port network is in the public network. The NAT mode is used between the LAN and WAN, and the NAT mode is used between the LAN and DMZ. The routing mode is used between DMZ and WAN.

The wide area network DMZ has few applications.

 

Routing mode

In routing mode, each interface (LAN, DMZ, and WAN) is in routing mode. IP addresses of different network segments configured for each interface can still access each other directly, and the source IP address is not converted.

Similar to a layer-3 switch, a LAN can be used to divide different network segments.

 

Full mode

The full mode is NAT mode + routing mode. The LAN (DMZ in LAN and LAN mode) and WAN are in NAT mode, while the other network segments and WAN are in routing mode.

Note:TL-ER6520G and TL-ER7520G are more flexible. If you set a NAPT rule for a CIDR block and the outbound interface is WAN, the CIDR block and the WAN are in NAT mode; if no NAPT rule is set, the CIDR block and other CIDR blocks are in the routing mode.

Generally, there are few full-mode applications.