Chapter 3: Advanced Configuration
Network Web Page Group
WAN Web Page (Fig. 22)
This page gives you the ability to enter some data your cable company may require, as explained before in Mandatory User Configuration. In addition, it enables you to view your WAN side IP address and lease information.
Your gateway can provide NAT/PAT (Network and Port Address Translation) as an element of security to prevent others from reaching your PCs when not authorized. To accomplish this, the gateway watches packets you send from your PC to Internet sites. Each time you send to a site (destination IP address) and application at that site (port), it translates your PC’s original IP and source port to new ones, and adds a row to its Connection Table maintained internally. (Note the different meaning of ‘connection’ here to describe an IP connection versus a physical cabling connection). If and when that site/application replies, it looks up the connection and reverses the IP/port process to direct the response to your PC.
The Connection Table manages itself, but you can also force this table to be cleared manually. To do this, click the Renew NAT Lease button.
You can enter a spoofed MAC address that causes your gateway networking stack to use that MAC address when communicating instead of the usual WAN MAC address (CM label + 2, as explained in Chapter 2). Enter the desired MAC address and click Apply.
Caution: If you enter a MAC address in use by another party, it can cause an address conflict on the network that could affect both you and that party.
Fig. 22
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