User's Manual

URL Filter

URL (Uniform Resource Locator) (e.g. an address in the form of http://www.abcde.com or http://

www.example.com) lter rule allows you to prevent users on your network from accessing specic

websites dened by their URL. There are no predened URL lter rules, therefore you can add

lter rules to meet your requirements.

Keywords Filtering: Allow blocking against specic keywords within a particular URL rather

than having to specify a complete URL (e.g. to block any image called “advertisement.gif”). When

enabled, your specied keywords list will be checked to see if any keywords are present in URLs

accessed to determine if the connection attempt should be blocked. Please note that the URL lter

blocks web browser (HTTP) connection attempts using port 80 only.

For example, if the URL is http://www.abc.com/abcde.html, it will be dropped as the keyword

“abcde” occurs in the URL.

Domains Filtering: This function checks the whole URL not the IP address, in URLs accessed

against your list of domains to block or allow. If it is matched, the URL request will be sent (Trusted)

or dropped (Forbidden). For this function to be activated, both check-boxes must be checked. Here

is the checking procedure:

1. Check the domain in the URL to determine if it is in the trusted list. If yes, the connection attempt

is sent to the remote web server.

2. If not, check if it is listed in the forbidden list. If yes, then the connection attempt will be

dropped.

3. If the packet does not match either of the above two items, it is sent to the remote web server.