User`s guide

5: Security Management
Overview
• Block URL – Ability to block a specific website by configuring IP address, URL or Keywords.
• Access Filter – Ability to block all Internet access, a known port or user defined ports by group
access.
• Session Limit – Ability to limit users Internet access when the device detects new sessions that
exceed the maximum value in the sampling time, for example, virus, syn flood, etc.
• SysFilter Exception – This feature allows you to configure an unrecognized port, allowing those
packets to be processed, enabling some programs to run more smoothly. This is also applicable
for some future applications that may need this mechanism in order to work well.
Block URL
This feature allows you to block access to undesirable Web sites. You can block by URL, IP address,
or Keyword. You can also have different blocking settings for different groups of PCs.
• In operation, every URL is searched to see if it matches or contains any of the URLs or keywords
entered here. Then, after a DNS lookup, it determines the IP address of the requested site and
checks it against IP address entries on this screen.
• Note that a single IP address may host many Web sites (shared IP). Entering an IP address on
this screen will block all Web sites that may be hosted on that IP address.
Figure 5-1: Block URL
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