vii
Restoring the Factory Default Configuration . . . . . . . . . . . . . . . .  2-36
Configuring Front-Panel Security  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-37
Disabling the Clear Password Function of the Clear Button  . . .  2-40
Re-Enabling the Clear Button and Setting or 
Changing the “Reset-On-Clear” Operation  . . . . . . . . . . . . . . . . . . 2-41
Changing the Operation of the Reset+Clear Combination  . . . . . 2-42
Password Recovery  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  2-44
Disabling or Re-Enabling the Password Recovery Process . . . . . . . .  2-44
Password Recovery Process  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-46
3 Virus Throttling (Connection-Rate Filtering)
Overview of Connection-Rate Filtering  . . . . . . . . . . . . . . . . . . . . . . . . . 3-1
Features and Benefits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2
General Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  3-3
Filtering Options   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  3-3
Sensitivity to Connection Rate Detection . . . . . . . . . . . . . . . . . . . .  3-4
Application Options  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  3-4
Operating Rules  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  3-5
Unblocking a Currently Blocked Host   . . . . . . . . . . . . . . . . . . . . . . 3-6
General Configuration Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-7
For a network that is relatively attack-free:   . . . . . . . . . . . . . . . . . . . . . 3-7
For a network that appears to be under significant attack: . . . . . . . . . 3-8
Configuring Connection-Rate Filtering  . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
Global and Per-Port Configuration  . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  3-9
Enabling Connection-Rate Filtering and Configuring
Sensitivity  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10
Configuring the Per-Port Filtering Mode   . . . . . . . . . . . . . . . . . . .  3-11
Example of a Basic Connection-Rate Filtering Configuration . .  3-12
Viewing and Managing Connection-Rate Status  . . . . . . . . . . . . . . . . . 3-14
Viewing Connection-Rate Configuration   . . . . . . . . . . . . . . . . . . . 3-14
Listing Currently-Blocked Hosts   . . . . . . . . . . . . . . . . . . . . . . . . . .  3-16
Unblocking Currently-Blocked Hosts  . . . . . . . . . . . . . . . . . . . . . . 3-16
Configuring and Applying Connection-Rate ACLs  . . . . . . . . . . . . . .  3-18
Connection-Rate ACL Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  3-19