ZyXEL Communications P-2602 User Manual

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P-2602H(W)(L)-DxA Series User’s Guide
Chapter 14 Firewall Configuration
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Figure 112   Firewall Example: Rules: MyService 
14.8  DoS Thresholds 
For DoS attacks, the ZyXEL Device uses thresholds to determine when to drop sessions that 
do not become fully established. These thresholds apply globally to all sessions.
You can use the default threshold values, or you can change them to values more suitable to 
your security requirements.
 to configure thresholds.  
14.8.1  Threshold Values
Tune these parameters when something is not working and after you have checked the firewall 
counters. These default values should work fine for most small offices. Factors influencing 
choices for threshold values are:
• The maximum number of opened sessions.
• The minimum capacity of server backlog in your LAN network.
• The CPU power of servers in your LAN network.
• Network bandwidth. 
• Type of traffic for certain servers.
If your network is slower than average for any of these factors (especially if you have servers 
that are slow or handle many tasks and are often busy), then the default values should be 
reduced.