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QoS processing flow in an AC
Figure 3 QoS processing flow
Traffic policing
Priority marking
Classify the
traffic
Classification
Packets received
on the interface
Tokens
Drop
Other
proce
ssing
Token bucket
CAR Remark
Toekn
Classify the
traffic
Classification
Packets to be
sent out the
interface
Drop
Other
proces
sing
Drop
Queuing
Enqueue
Queue 0
Queue 1
Queue 2
Queue N
...
Dequeue
Transmit
Queues
Token bucket
Traffic policing
Traffic shaping
Congestion
avoidance
CAR
GTS
WRED
Congestion
management
Figure 3 shows how the QoS module processes traffic:
Traffic classifier identifies and classifies traffic for subsequent QoS actions.
The QoS module takes various QoS actions on classified traffic as configured,
depending on the traffic processing phase and network status. For example, you
may configure the QoS module to perform traffic policing for incoming traffic,
traffic shaping for outgoing traffic, congestion avoidance before congestion
occurs, and congestion management when congestion occurs.