LevelOne FGL-2870 - Manual (Page 601)

Automatic Traffic Control Commands
4-235
4
Usage Guidelines
ATC includes storm control for broadcast or multicast traffic. The control response
for either of these traffic types is the same, as shown in the following diagrams.
Storm control by limiting the traffic rate:
The key elements of this diagram are described below:
• Alarm Fire Threshold – The highest acceptable traffic rate. When ingress traffic
exceeds the threshold, ATC sends a Storm Alarm Fire Trap and logs it.
• When traffic exceeds the alarm fire threshold and the apply timer expires, a traffic
control response is applied, and a Traffic Control Apply Trap is sent and logged.
• Alarm Clear Threshold – The lower threshold beneath which an control response
can be automatically terminated after the release timer expires. When ingress
traffic falls below this threshold, ATC sends a Storm Alarm Clear Trap and logs it.
• When traffic falls below the alarm clear threshold after the release timer expires,
traffic control will be stopped and a Traffic Control Release Trap sent and logged.
• The traffic control response of rate limiting can be released automatically or
manually. The control response of shuting down a port can only be released
manually.
Storm Alarm
Fire TRAP
Alarm Fire
Threshold
（1～255kpps）
AlarmClear
Threshold
（1～255kpps）
Traffic
[kpps]
Time
Traffic without storm control
Traffic with storm control
Apply Timer
expired
(0～300sec)
Auto Storm Control
Release Timer
expired
(0～300sec)
Storm Alarm
Fire TRAP
StromAlarm
ClearTRAP
TrafficControl
Apply Trap
StromAlarm
ClearTRAP
TrafficControl
Release Trap
Storm Alarm
Fire TRAP
Alarm Fire
Threshold
（1～255kpps）
AlarmClear
Threshold
（1～255kpps）
Traffic
[kpps]
Time
Traffic without storm control
Traffic with storm control
Apply Timer
expired
(0～300sec)
Auto Storm Control
Release Timer
expired
(0～300sec)
Storm Alarm
Fire TRAP
StromAlarm
ClearTRAP
TrafficControl
Apply Trap
StromAlarm
ClearTRAP
TrafficControl
Release Trap