D-Link DI-308 manual Router NAT

DI-308 ISDN Remote Router

Single

Global

IP Address

176.220.22.1

ISDN

PortWAN

Router NAT

Translator

LAN

Port

Local IP LAN

192.168.100.1

192.168.100.2 192.168.100.3 192.168.100.4 192.168.100.5

Please note that in the above diagram, the Gateway IP address settings for the local PC’s needs to be set to 192.168.100.1, the LAN IP address of the router.

NAT manipulates the IP addresses in packet headers on a one-to-one basis. An outgoing data packet (a packet originating from a computer on the local LAN and destined for a computer outside the private network) will have its IP address translated as shown below.

In the Outgoing Data Packet above, the Source IP address is the IP address that is translated by NAT. The Destination IP Address is the IP address of a computer outside the private network, on the Internet for example. And the Data portion of the packet is the information payload borne by the packet, for instance a request to view a web page.

The router logs the changes made to the IP header in its NAT table. The NAT table enables the router to send replies back to the local computer as shown below.

In the Inbound Data Packet above, the Destination IP Address is the IP address that is translated by NAT. The Source IP Address is the IP address of a computer outside the private network. And the Data portion of the packet is the information payload borne by the packet, for example, the contents of a web page.

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