Chapter 11 Firewall screens
193
Nortel Business Secure Router 252 Configuration — Basics
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 Business Secure
Router deletes half-open sessions, as required, to accommodate
new connection attempts.
The numbers, for example, 80 in the
One Minute Low
field and
100 in this field, cause the Business Secure Router to start deleting
half-open sessions when more than 100 session establishment
attempts are detected in the last minute, and to stop deleting
half-open sessions when fewer than 80 session establishment
attempts are 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 Business Secure
Router 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 Business
Secure Router 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 Business Secure Router 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,
choose a smaller number for a smaller network, a slower system or
limited bandwidth.
Blocking Period
When
TCP Maximum Incomplete
is reached you can choose to
either allow or block the next session. If you select the
Blocking
Period
check box, any new sessions are blocked for the length of
time you specify in the next field (min) and all old incomplete
sessions are cleared during this period. If you want strong security,
it is better to block the traffic for a short time, as it gives the server
some time to digest the loading.
(min)
Enter the length of
Blocking Period
in minutes.
Apply
Click
Apply
to save your changes to the Business Secure Router.
Reset
Click
Reset
to begin configuring this screen afresh.
Table 41
Attack alert
Label
Description
Summary of Contents for BSR252
Page 28: ...28 Tables NN47923 500 ...
Page 44: ...44 Chapter 1 Getting to know your Business Secure Router NN47923 500 ...
Page 52: ...52 Chapter 2 Introducing the WebGUI NN47923 500 ...
Page 70: ...70 Chapter 3 Wizard setup NN47923 500 ...
Page 96: ...96 Chapter 5 System screens NN47923 500 ...
Page 114: ...114 Chapter 7 WAN screens NN47923 500 Figure 27 WAN IP ...
Page 120: ...120 Chapter 7 WAN screens NN47923 500 Figure 31 Dial Backup Setup ...
Page 128: ...128 Chapter 7 WAN screens NN47923 500 ...
Page 152: ...152 Chapter 9 Static Route screens NN47923 500 ...
Page 194: ...194 Chapter 11 Firewall screens NN47923 500 ...
Page 210: ...210 Chapter 13 VPN NN47923 500 Figure 67 Summary IP Policies ...
Page 222: ...222 Chapter 13 VPN NN47923 500 Figure 71 VPN Branch Office rule setup ...
Page 256: ...256 Chapter 13 VPN NN47923 500 Figure 81 VPN Client Termination advanced ...
Page 260: ...260 Chapter 13 VPN NN47923 500 ...
Page 264: ...264 Chapter 14 Certificates NN47923 500 Figure 83 My Certificates ...
Page 270: ...270 Chapter 14 Certificates NN47923 500 Figure 85 My Certificate create ...
Page 274: ...274 Chapter 14 Certificates NN47923 500 Figure 86 My Certificate details ...
Page 282: ...282 Chapter 14 Certificates NN47923 500 Figure 89 Trusted CA details ...
Page 298: ...298 Chapter 14 Certificates NN47923 500 ...
Page 316: ...316 Chapter 16 IEEE 802 1x NN47923 500 ...
Page 320: ...320 Chapter 17 Authentication server NN47923 500 Figure 106 Local User database edit ...
Page 328: ...328 Chapter 17 Authentication server NN47923 500 ...
Page 376: ...376 Chapter 20 Logs Screens NN47923 500 Figure 150 Log settings ...
Page 386: ...386 Chapter 20 Logs Screens NN47923 500 ...
Page 393: ...Chapter 21 Call scheduling screens 393 Nortel Business Secure Router 252 Configuration Basics ...
Page 394: ...394 Chapter 21 Call scheduling screens NN47923 500 ...
Page 410: ...410 Chapter 22 Maintenance NN47923 500 ...