Traffic Policing On Layer 2 Atm Interfaces - Cisco ASR 9000 Series Configuration Manual

Traffic Policing on Layer 2 ATM Interfaces

can use this setting to determine how the traffic should be treated. For example, the Weighted Random Early
Detection (WRED) feature uses the IP precedence value to determine the probability that a packet is dropped.
If you want to mark traffic but do not want to use traffic policing, see the "Class-based, Unconditional Packet
Marking Examples" section to learn how to perform packet classification.
Marking IP fields on an MPLS-enabled interface results in non-operation on that particular interface.
Note
Traffic Policing on Layer 2 ATM Interfaces
Traffic policing is supported on the Layer 2 ATM interfaces in the ingress imposition path. The OAM cells
are policed along with the user cells unless the QoS policy is explicitly configured to exclude the OAM cells
from being policed.
Policing is supported for the virtual circuit (VC), and the virtual path (VP) modes. However, policing is
Note
not supported for the port mode on the Layer 2 ATM interfaces.
Different match criteria can be used in the policy map with class-default matching all the traffic including the
OAM cells.
Policing is performed on the ATM Adaptation Layer type 0 (AAL0) cells but translates to ATM Adaptation
Layer type 5 (AAL5) packets as described below:
• AAL5 packet conforms, if all the cells in the packet conform to peak cell rate (PCR) and sustainable
• AAL5 packet exceeds, if at least one cell does not conform to the SCR bucket.
• AAL5 packet violates, if at least one cell does not conform to the PCR bucket.
The following policer options are supported:
• Rate in cells per second, and percent
• Peak rate in cells per second, and percent
• Delay tolerance in microseconds
• Maximum burst size in cells
The following policer actions are supported on the Layer 2 ATM interfaces in the ingress direction:
• transmit
• drop
• set mpls exp imposition <exp> (AToM only)
• set qos-group <qos-group> (AToM and local switching)
• set discard-class <discard-class> (AToM and local switching)
• set atm-clp (Exceed action only, AToM and local switching)
Cisco ASR 9000 Series Aggregation Services Router Modular Quality of Service Configuration Guide, Release
6.1.x
64
cell rate (SCR) buckets.
Configuring Modular QoS Congestion Management