ZyXEL Communications P-870HW-I User Manual

P-870HW-I1 User’s Guide

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Chapter 11 Firewalls

• Never e-mail sensitive information such as passwords, credit card information, etc., 

without encrypting the information first.

• Never submit sensitive information via a web page unless the web site uses secure 

connections. You can identify a secure connection by looking for a small “key” icon on 
the bottom of your browser (Internet Explorer 3.02 or better or Netscape 3.0 or better). If 
a web site uses a secure connection, it is safe to submit information. Secure web 
transactions are quite difficult to crack.

• Never reveal your IP address or other system networking information to people outside 

your company. Be careful of files e-mailed to you from strangers. One common way of 
getting BackOrifice on a system is to include it as a Trojan horse with other files.

• Change your passwords regularly. Also, use passwords that are not easy to figure out. 

The most difficult passwords to crack are those with upper and lower case letters, 
numbers and a symbol such as % or #.

• Upgrade your software regularly. Many older versions of software, especially web 

browsers, have well known security deficiencies. When you upgrade to the latest 
versions, you get the latest patches and fixes.

• If you use “chat rooms” or IRC sessions, be careful with any information you reveal to 

strangers.

• If your system starts exhibiting odd behavior, contact your ISP. Some hackers will set off 

hacks that cause your system to slowly become unstable or unusable. 

• Always shred confidential information, particularly about your computer, before 

throwing it away. Some hackers dig through the trash of companies or individuals for 
information that might help them in an attack.

Use this screen to activate the firewall and to set the default rules for each direction. To open 
this screen, click Security > Firewall > General.

Figure 85   Security > Firewall > General