Ethernet Interface Lan - Netopia 2200 series Software User's Manual

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:
WAN
Internet
Ethernet
Interface
Embedded Admin Services:
HTTP-Web Server and Telnet Server Port
340
Netopia Gateway
NAT
LAN
Ethernet
Interface
NAT-protected
LAN stations