Chapter 9 Firewalls
It’s like having multiple LAN networks that actually use the same physical cables and ports. By putting your LAN and Gateway A in different subnets, all returning network traffic must pass through the ZyXEL Device to your LAN. The following steps describe such a scenario.
1A computer on the LAN initiates a connection by sending a SYN packet to a receiving server on the WAN.
2The ZyXEL Device reroutes the packet to Gateway A, which is in Subnet 2.
3The reply from the WAN goes to the ZyXEL Device.
4The ZyXEL Device then sends it to the computer on the LAN in Subnet 1.
Figure 94 IP Alias
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2
ISP 2
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Subnet 2 |
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170 |
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