ZyWALL 5 User’s Guide
184
Chapter 10 Firewall Screens
One Minute High
This is the rate of new half-open sessions that causes the firewall to start deleting
half-open sessions. When the rate of new connection attempts rises above this
number, the ZyWALL deletes half-open sessions as required to accommodate
new connection attempts.
The numbers, say 80 in the
One Minute Low
field and 100 in this field, cause the
ZyWALL to start deleting half-open sessions when more than 100 session
establishment attempts have been detected in the last minute, and to stop
deleting half-open sessions when fewer than 80 session establishment attempts
have been detected in the last minute.
Maximum
Incomplete Low
This is the number of existing half-open sessions that causes the firewall to stop
deleting half-open sessions. The ZyWALL continues to delete half-open requests
as necessary, until the number of existing half-open sessions drops below this
number.
Maximum
Incomplete High
This is the number of existing half-open sessions that causes the firewall to start
deleting half-open sessions. When the number of existing half-open sessions
rises above this number, the ZyWALL deletes half-open sessions as required to
accommodate new connection requests. Do not set
Maximum Incomplete High
to lower than the current
Maximum
Incomplete
Low
number.
The above values, say 80 in the
Maximum Incomplete Low
field and 100 in this
field, cause the ZyWALL to start deleting half-open sessions when the number of
existing half-open sessions rises above 100, and to stop deleting half-open
sessions with the number of existing half-open sessions drops below 80.
TCP Maximum
Incomplete
This is the number of existing half-open TCP sessions with the same destination
host IP address that causes the firewall to start dropping half-open sessions to
that same destination host IP address. Enter a number between 1 and 256. As a
general rule, you should choose a smaller number for a smaller network, a slower
system or limited bandwidth.
Action taken when
the TCP Maximum
Incomplete
threshold is
reached.
Delete the oldest
half open session
when new
connection request
comes
Select this radio button to clear the oldest half open session when a new
connection request comes.
Deny new
connection request
for
Select this radio button and specify for how long the ZyWALL should block new
connection requests when
TCP Maximum Incomplete
is reached.
Enter the length of blocking time in minutes (between 1 and 256).
Apply
Click
Apply
to save your changes back to the ZyWALL.
Reset
Click
Reset
to begin configuring this screen afresh.
Table 55
Firewall Threshold (continued)
LABEL
DESCRIPTION
Summary of Contents for ZyXEL ZyWALL 5
Page 1: ...ZyWALL 5 Internet Security Appliance User s Guide Version 3 64 3 2005 ...
Page 2: ......
Page 26: ...ZyWALL 5 User s Guide 24 ...
Page 44: ...ZyWALL 5 User s Guide 42 ...
Page 86: ...ZyWALL 5 User s Guide 84 Chapter 3 Wizard Setup ...
Page 96: ...ZyWALL 5 User s Guide 94 Chapter 4 LAN Screens ...
Page 102: ...ZyWALL 5 User s Guide 100 Chapter 5 Bridge Screens ...
Page 130: ...ZyWALL 5 User s Guide 128 Chapter 7 WAN Screens Figure 45 WAN PPPoE Encapsulation ...
Page 138: ...ZyWALL 5 User s Guide 136 Chapter 7 WAN Screens Figure 50 Dial Backup Setup ...
Page 144: ...ZyWALL 5 User s Guide 142 Chapter 7 WAN Screens ...
Page 152: ...ZyWALL 5 User s Guide 150 Chapter 8 DMZ Screens ...
Page 179: ...ZyWALL 5 User s Guide Chapter 10 Firewall Screens 177 Figure 73 My Service Rule Configuration ...
Page 220: ...ZyWALL 5 User s Guide 218 Chapter 13 Introduction to IPSec ...
Page 238: ...ZyWALL 5 User s Guide 236 Chapter 14 VPN Screens Figure 110 VPN Rules IKE Network Policy Edit ...
Page 261: ...ZyWALL 5 User s Guide Chapter 15 Certificates 259 Figure 122 My Certificate Details ...
Page 280: ...ZyWALL 5 User s Guide 278 Chapter 16 Authentication Server Figure 133 Local User Database ...
Page 317: ...ZyWALL 5 User s Guide Chapter 19 Bandwidth Management 315 ...
Page 318: ...ZyWALL 5 User s Guide 316 Chapter 19 Bandwidth Management ...
Page 352: ...ZyWALL 5 User s Guide 350 Chapter 21 Remote Management ...
Page 366: ...ZyWALL 5 User s Guide 364 Chapter 23 Logs Screens Figure 188 Log Settings ...
Page 389: ...ZyWALL 5 User s Guide Chapter 24 Maintenance 387 Figure 210 Restart Screen ...
Page 390: ...ZyWALL 5 User s Guide 388 Chapter 24 Maintenance ...
Page 416: ...ZyWALL 5 User s Guide 414 Chapter 27 WAN and Dial Backup Setup ...
Page 432: ...ZyWALL 5 User s Guide 430 Chapter 30 DMZ Setup ...
Page 492: ...ZyWALL 5 User s Guide 490 Chapter 37 System Information Diagnosis ...
Page 508: ...ZyWALL 5 User s Guide 506 Chapter 38 Firmware and Configuration File Maintenance ...
Page 520: ...ZyWALL 5 User s Guide 518 Chapter 40 Remote Management ...
Page 536: ...ZyWALL 5 User s Guide 534 Chapter 42 Troubleshooting Figure 343 Java Sun ...
Page 564: ...ZyWALL 5 User s Guide 562 Appendix C IP Subnetting ...
Page 570: ...ZyWALL 5 User s Guide 568 Appendix E PPTP ...
Page 571: ...ZyWALL 5 User s Guide 569 ...
Page 572: ...ZyWALL 5 User s Guide 570 ...
Page 590: ...ZyWALL 5 User s Guide 588 Appendix G Triangle Route ...
Page 620: ...ZyWALL 5 User s Guide 618 Appendix J Importing Certificates ...
Page 622: ...ZyWALL 5 User s Guide 620 Appendix K Command Interpreter ...
Page 628: ...ZyWALL 5 User s Guide 626 Appendix L Firewall Commands ...
Page 632: ...ZyWALL 5 User s Guide 630 Appendix M NetBIOS Filter Commands ...
Page 638: ...ZyWALL 5 User s Guide 636 Appendix O Brute Force Password Guessing Protection ...
Page 660: ...ZyWALL 5 User s Guide 658 Appendix Q Log Descriptions ...