R0106-HP MSR Router Series ACL and QoS Configuration Guide(V7)
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• Control plane—The QoS policy takes effect on the traffic received on the control plane.
• Management interface control plane—The QoS policy takes effect on the traffic sent from the
management interface to the control plane.
You can modify traffic classes, traffic behaviors, and class-behavior associations in a QoS policy even
after it is applied. If a traffic class references an ACL for traffic classification, you can delete or modify the
ACL.
Applying the QoS policy to an interface or PVC
A QoS policy can be applied to multiple interfaces or PVCs, but only one QoS policy can be applied to
one direction (inbound or outbound) of an interface or PVC.
The QoS policy applied to the outgoing traffic on an interface or PVC does not regulate local packets,
which are critical protocol packets sent by the local system for operation maintenance. The most common
local packets include link maintenance, routing, LDP, RSVP, and SSH packets.
To apply the QoS policy to an interface or PVC:
Ste
p
Command
Remarks
1. Enter system view.
system-view
N/A
2. Enter interface or PVC
view.
• Enter interface view:
interface interface-type
interface-number
• Enter PVC view:
a. interface atm interface-number
b. pvc vpi/vci
Settings in interface view take
effect on the current interface.
Settings in PVC view take
effect on the current PVC.
3. Apply the QoS policy to
the interface or PVC.
qos apply policy policy-name { inbound |
outbound }
By default, no QoS policy is
applied to an interface or
PVC.
Applying the QoS policy to the control plane
A device provides the data plane and the control plane:
• Data plane—The units at the data plane are responsible for receiving, transmitting, and switching
(forwarding) packets, such as various dedicated forwarding chips. They deliver super processing
speeds and throughput.
• Control plane—The units at the control plane are processing units running most routing and
switching protocols. They are responsible for protocol packet resolution and calculation, such as
CPUs. Compared with data plane units, the control plane units allow for great packet processing
flexibility but have lower throughput.
When the data plane receives packets that it cannot recognize or process, it transmits them to the control
plane. If the transmission rate exceeds the processing capability of the control plane, the control plane
will be busy handling undesired packets and fail to handle legitimate packets correctly or timely. As a
result, protocol performance is affected.
To address this problem, apply a QoS policy to the control plane to take QoS actions, such as traffic
filtering or rate limiting, on inbound traffic. This makes sure the control plane can correctly receive,
transmit, and process packets.