ZyXEL Communications LTE3301-PLUS, Руководство пользователя

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Chapter 17 Firewall
Nebula Mobile Router User’s Guide
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6
Protect against IP spoofing by making sure the firewall is active.
7
Keep the firewall in a secured (locked) room.
17.7.3 Security Considerations
Note: Incorrectly configuring the firewall may block valid access or introduce security risks to
the Zyxel Device 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
(Internet Relay Chat) 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.