Chapter 14 Firewall
VMG1312-T10C User’s Guide
168
Figure 114
“Triangle Route” Problem
14.6.4.2 Solving the “Triangle Route” Problem
If you have the Device allow triangle route sessions, traffic from the WAN can go directly to a LAN
computer without passing through the Device and its firewall protection.
Another solution is to use IP alias. IP alias allows you to partition your network into logical sections
over the same Ethernet interface. Your Device supports up to three logical LAN interfaces with the
Device being the gateway for each logical network.
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 Device to your LAN. The following steps describe such a scenario.
1
A computer on the LAN initiates a connection by sending a SYN packet to a receiving server on the
WAN.
2
The Device
reroutes the packet to Gateway A, which is in Subnet 2.
3
The reply from the WAN goes to the Device.
4
The Device then sends it to the computer on the LAN in Subnet 1.
Figure 115
IP Alias
1
2
3
WAN
LAN
A
ISP 1
ISP 2
1
2
3
LAN
A
ISP 1
ISP 2
4
WAN
Subnet 1
Subnet 2
Summary of Contents for VMG1312-T10C
Page 4: ...Contents Overview VMG1312 T10C User s Guide 4 ...
Page 12: ...Table of Contents VMG1312 T10C User s Guide 12 ...
Page 13: ...13 PART I User s Guide ...
Page 14: ...14 ...
Page 20: ...Chapter 1 Introduction VMG1312 T10C User s Guide 20 ...
Page 28: ...28 ...
Page 34: ...Chapter 4 Connection Status and System Info VMG1312 T10C User s Guide 34 ...
Page 106: ...Chapter 7 Home Networking VMG1312 T10C User s Guide 112 ...
Page 144: ...Chapter 13 Filter VMG1312 T10C User s Guide 152 ...
Page 164: ...Chapter 15 Parental Control VMG1312 T10C User s Guide 172 ...
Page 172: ...Chapter 16 Certificates VMG1312 T10C User s Guide 180 ...
Page 178: ...Chapter 17 System Monitor VMG1312 T10C User s Guide 186 ...
Page 180: ...Chapter 18 User Account VMG1312 T10C User s Guide 188 ...
Page 184: ...Chapter 20 System VMG1312 T10C User s Guide 192 ...
Page 190: ...Chapter 22 Log Setting VMG1312 T10C User s Guide 198 ...
Page 196: ...Chapter 24 Backup Restore VMG1312 T10C User s Guide 204 ...
Page 214: ...Chapter 26 Diagnostic VMG1312 T10C User s Guide 222 ...
Page 232: ...Appendix B Legal Information VMG1312 T10C User s Guide 240 ...