Chapter 15 Firewall
AMG1302/AMG1202-TSeries User’s Guide
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11
Protect against IP spoofing by making sure the firewall is active.
12
Keep the firewall in a secured (locked) room.
15.6.3 Security Considerations
Note: Incorrectly configuring the firewall may block valid access or introduce security
risks to the AMG1302/AMG1202-TSeries and your protected network. Use caution
when creating or deleting firewall rules and test your rules after you configure
them.
Consider these security ramifications before creating a rule:
1
Does this rule stop LAN users from accessing critical resources on the Internet? For example, if IRC
is blocked, are there users that require this service?
2
Is it possible to modify the rule to be more specific? For example, if IRC is blocked for all users, will
a rule that blocks just certain users be more effective?
3
Does a rule that allows Internet users access to resources on the LAN create a security
vulnerability? For example, if FTP ports (TCP 20, 21) are allowed from the Internet to the LAN,
Internet users may be able to connect to computers with running FTP servers.
4
Does this rule conflict with any existing rules?
Once these questions have been answered, adding rules is simply a matter of entering the
information into the correct fields in the web configurator screens.
15.6.4 Triangle Route
When the firewall is on, your AMG1302/AMG1202-TSeries acts as a secure gateway between your
LAN and the Internet. In an ideal network topology, all incoming and outgoing network traffic
passes through the AMG1302/AMG1202-TSeries to protect your LAN against attacks.
Figure 90
Ideal Firewall Setup
15.6.4.1 The “Triangle Route” Problem
A traffic route is a path for sending or receiving data packets between two Ethernet devices. You
may have more than one connection to the Internet (through one or more ISPs). If an alternate
gateway is on the LAN (and its IP address is in the same subnet as the AMG1302/AMG1202-
TSeries’s LAN IP address), the “triangle route” (also called asymmetrical route) problem may occur.
The steps below describe the “triangle route” problem.
1
2
WAN
LAN
Summary of Contents for AMG1202-T series
Page 4: ...Contents Overview AMG1302 AMG1202 TSeries User s Guide 4 ...
Page 13: ...13 PART I User s Guide ...
Page 14: ...14 ...
Page 20: ...Chapter 1 Introduction AMG1302 AMG1202 TSeries User s Guide 20 ...
Page 28: ...Chapter 2 Introducing the Web Configurator AMG1302 AMG1202 TSeries User s Guide 28 ...
Page 61: ...Chapter 4 Tutorials AMG1302 AMG1202 TSeries User s Guide 61 Tutorial Advanced QoS Class Setup ...
Page 64: ...Chapter 4 Tutorials AMG1302 AMG1202 TSeries User s Guide 64 ...
Page 65: ...65 PART II Technical Reference ...
Page 66: ...66 ...
Page 72: ...Chapter 5 Connection Status and System Info Screens AMG1302 AMG1202 TSeries User s Guide 72 ...
Page 120: ...Chapter 7 Wireless LAN AMG1302 AMG1202 TSeries User s Guide 120 ...
Page 150: ...Chapter 10 Quality of Service QoS AMG1302 AMG1202 TSeries User s Guide 150 ...
Page 160: ...Chapter 11 Network Address Translation NAT AMG1302 AMG1202 TSeries User s Guide 160 ...
Page 172: ...Chapter 14 Filters AMG1302 AMG1202 TSeries User s Guide 172 ...
Page 194: ...Chapter 16 Parental Control AMG1302 AMG1202 TSeries User s Guide 194 ...
Page 200: ...Chapter 17 Certificate AMG1302 AMG1202 TSeries User s Guide 200 ...
Page 206: ...Chapter 19 Traffic Status AMG1302 AMG1202 TSeries User s Guide 206 ...
Page 208: ...Chapter 20 User Account AMG1302 AMG1202 TSeries User s Guide 208 ...
Page 212: ...Chapter 21 TR 069 Client AMG1302 AMG1202 TSeries User s Guide 212 ...
Page 216: ...Chapter 22 System Settings AMG1302 AMG1202 TSeries User s Guide 216 ...
Page 222: ...Chapter 24 Backup Restore AMG1302 AMG1202 TSeries User s Guide 222 ...
Page 234: ...Chapter 25 Remote Management AMG1302 AMG1202 TSeries User s Guide 234 ...
Page 238: ...Chapter 26 Diagnostic AMG1302 AMG1202 TSeries User s Guide 238 ...
Page 244: ...Chapter 27 Troubleshooting AMG1302 AMG1202 TSeries User s Guide 244 ...
Page 294: ...Appendix D Wireless LANs AMG1302 AMG1202 TSeries User s Guide 294 ...
Page 304: ...Appendix E IPv6 AMG1302 AMG1202 TSeries User s Guide 304 ...
Page 320: ...Index AMG1302 AMG1202 TSeries User s Guide 320 ...