DSL LAN Extender 200 User’s Guide
© 2002 Black Box Corporation
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Case (E) DSL LAN Extender CPs NAT enabled, all machines using private IP
As shown in the example on next page, the client side computers are all using private IP addresses in
subnetwork 192.168.1.0. To the outside world, all machines are using a single IP address, that is the main
IP address of the DSL LAN Extender
CP, 192.168.1.1. This includes customer side servers if they exist.
If the site wants to host its own Web server or e-mail server, their IP addresses need to be entered in the
DSL LAN Extender
CP device. And users need to register through DNS with both e-mail and Web
servers as 194.1.2. That is, both e-mail server and Web server are known as having IP address of the DSL
LAN Extender CP device, rather than their real IP addresses, which are private.
Network Structure:
ISP assigns IP addresses 194.1.1.1 to 194.1.1.7 to the customer site.
Customer site has NAT enabled, all machines using private IP addresses in subnetwork 192.168.1.0.
Customer Site Capabilities:
A single IP address serves the whole group, including e-mail and Web servers.
The e-mail server (using private IP 192.168.1.2) can be accessed from both inside and outside.
The Web server (using private IP 192.168.1.3) can be accessed from both inside and outside.
Configurations:
All machines’ IP settings are shown in the chart.
See box CP_A for the settings in this device.
Register through DNS with both e-mail and Web servers as 194.1.2.1.
Example Traffic Path:
PC_A1 sends a packet to the Internet: PC_A1
→
CP_A
→
CO_A
→
WAN Router
→
Internet
PC_S1 sends a packet to the Internet: PC_S1
→
CP_A
→
CO_A
→
WAN Router
→
Internet
