Accedian EtherNID EE, Руководство администратора

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10: Traffic Shaper
BLUE performs queue management based on link utilization. It maintains a marking probability pm to either mark or drop
the packets. If the queue is continually dropping the packets , pm is incremented by a factor / 1.
If the queue is empty or link is idle, pm is decremented by a factor / 2 . The value of / 1 should be set significantly larger
than / 2. This is because link is underutilized when the congestion management is either too aggressive or too
conservative, but packet loss occurs only when the congestion mechanism is too conservative.
BLUE uses one more parameter
freeze_time, which determines the time interval between two successive updates of pm.
It allows the changes in the marking probability to take effect before the value is updated again.
Before we move to the next step, traffic shaper statistics, we need to get some traffic flowing through the shapers. The
basic flow of information is:
•
Traffic is received on the client port.
•
There is a policy or policies on the port to set the PCP on the incoming traffic, This PCP value will then be used to
map the traffic to a specific shaper or the real-time queue.
For this example we will take VLAN 100 being received on the client port and send it to shaper-1.
Create an L2 filter for VLAN100 and apply
Go to Traffic > L2 filter
Then we need to use this filter in a policy on the client port