Figure 64 Ip Alias - ZyXEL Communications P-793H User Manual

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 P-793H v2 to your LAN. The following steps
describe such a scenario.
A computer on the LAN initiates a connection by sending a SYN packet to a
1
receiving server on the WAN.
The P-793H v2 reroutes the packet to Gateway A, which is in Subnet 2.
2
The reply from the WAN goes to the P-793H v2.
3
The P-793H v2 then sends it to the computer on the LAN in Subnet 1.
4

Figure 64 IP Alias

LAN
P-793H v2 User's Guide
Subnet 1
1
4
2
3
Subnet 2
WAN
ISP 1
ISP 2
A
Chapter 9 Firewalls
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