from routers on networks connected to its WAN interface. In other words, the end com- puter stations on your LAN are invisible from the Internet.

Only a single WAN IP address is required to provide this security support for your entire LAN.

LAN sites that communicate through an Internet Service Provider typically enable NAT, since they usually purchase only one IP address from the ISP.

When NAT is ON, the Netopia Gateway “proxies” for the end computer stations on your network by pretending to be the originating host for network communications from non- originating networks. The WAN interface address is the only IP address exposed.

The Netopia Gateway tracks which local hosts are communicating with which remote hosts. It routes packets received from remote networks to the correct computer on the LAN (Ethernet) interface.

When NAT is OFF, a Netopia Gateway acts as a traditional TCP/IP router, all LAN com- puters/devices are exposed to the Internet.

A diagram of a typical NAT-enabled LAN follows:

 

Netopia Gateway

LAN

Internet

WAN

Ethernet

Ethernet

 

 

Interface

Interface

 

NAT

 

 

 

NAT-protected

 

 

LAN stations

 

Embedded Admin Services:

 

 

HTTP-Web Server and Telnet Server Port

340

 

 

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