ZyXEL Communications P-661HNU - Firewall Technical Reference; Guidelines for Enhancing Security with Your Firewall; Security Considerations

Chapter 13 Firewall
P-661HNU-Fx User’s Guide
203
13.4 Firewall Technical Reference
This section provides some technical background information about the topics
covered in this chapter.
13.4.1 Guidelines For Enhancing Security With Your Firewall
1 Change the default password via web configurator.
2 Think about access control before you connect to the network in any way.
3 Limit who can access your ZyXEL Device.
4 Don't enable any local service (such as Telnet or FTP) that you don't use. Any
enabled service could present a potential security risk. A determined hacker might
be able to find creative ways to misuse the enabled services to access the firewall
or the network.
5 For local services that are enabled, protect against misuse. Protect by configuring
the services to communicate only with specific peers, and protect by configuring
rules to block packets for the services at specific interfaces.
6 Keep the firewall in a secured (locked) room.
13.4.2 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 is blocked, are there users that require this service?
Delete Select a service in the Blocked Services, and click this to remove the
service from the list.
Clear All Click this to remove all the services in the Blocked Services list.
Apply Click Apply to save your changes.
Cancel Click Cancel to restore your previously saved settings.
Table 49 Security > Firewall > Services (continued)
LABEL DESCRIPTION