What Can Go Wrong; How To Block Facebook - ZyXEL Communications ZyWALL 110 Handbook

Figure 122
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Figure 123 Monitor > Log

3.4.3 What Can Go Wrong?

You may find that certain rules are triggering too many false positives or false negatives. A false
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positive is when valid traffic is flagged as an attack. A false negative is when invalid traffic is
wrongly allowed to pass through the ZyWALL/USG. As each network is different, false positives and
false negatives are common on initial ADP deployment. You could create a new 'monitor profile'
that creates logs but all actions are disabled. Observe the logs over time and try to eliminate the
causes of the false alarms. When you're satisfied that they have been reduced to an acceptable
level, you could then create an 'inline profile' whereby you configure appropriate actions to be taken
when a packet matches a detection.

3.5 How To Block Facebook

This is an example of using a ZyWALL/USG UTM Profile in a Security Policy to block access to a
specific social network service. You can use Content Filter, SSL Inspection and Policy Control to
make sure that a certain web page cannot be accessed through both HTTP and HTTPS protocols.
Chapter 3 Protect Your Network with UTM
2 Go to the ZyWALL/USG Monitor > Log, you will see [warn] log message
such as below.
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