Lers At The Eompls Edge - Cisco WS-SUP32-GE-3B - Supervisor Engine 32 Software Configuration Manual

Understanding MPLS QoS
The results of each QoS TCAM lookup yield an index into RAM that contains policer configuration and
policing counters. Additional RAM contains the microflow policer configuration; the microflow
policing counters are maintained in the respective NetFlow entries that match the QoS ACL.
The results of ingress and egress aggregate and microflow policing are combined into a final policing
decision. The out-of-profile packets can be either dropped or marked down in the DSCP.
This section describes MPLS QoS for the following:
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The following sections refer to QoS features for LAN ports, OSM ports, and FlexWAN ports. For details
Note
about how the different features work, refer to the appropriate documentation.

LERs at the EoMPLS Edge

This section summarizes the Ethernet over MPLS (EoMPLS) QoS features that function on the LERs.
EoMPLS QoS support is similar to IP-to-MPLS QoS:
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Ethernet to MPLS
For Ethernet to MPLS, the ingress interface, MPLS QoS, and egress interface features are similar to
corresponding features for IP to MPLS. For more information, see these sections:
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Catalyst Supervisor Engine 32 PISA Cisco IOS Software Configuration Guide, Release 12.2ZY
39-8
LERs at the EoMPLS Edge, page 39-8
LERs at the IP Edge (MPLS, MPLS VPN), page 39-9
LSRs at the MPLS Core, page 39-13
For EoMPLS, if the port is untrusted, the CoS trust state is automatically configured for VC type 4
(VLAN mode), not for VC type 5 (port mode). 802.1q CoS preservation across the tunnel is similar.
Packets received on tunnel ingress are treated as untrusted for EoMPLS interfaces, except for VC
Type 4 where trust CoS is automatically configured on the ingress port and policy marking is not
applied.
If the ingress port is configured as trusted, packets received on an EoMPLS interface are never
marked by QoS policy in the original IP packet header (marking by IP policy works on untrusted
ports).
802.1p CoS is preserved from entrance to exit, if available through the 802.1q header.
After exiting the tunnel egress, queueing is based on preserved 802.1p CoS if 1p tag has been
tunnelled in the EoMPLS header (VC type 4); otherwise, queuing is based on the CoS derived from
the QoS decision.
Classification for IP-to-MPLS, page 39-9
Classification for IP-to-MPLS MPLS QoS, page 39-10
Classification at IP-to-MPLS Ingress Port, page 39-10
Classification at IP-to-MPLS Egress Port, page 39-10
Chapter 39 Configuring MPLS QoS
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