Classification And Marking With A Layer 2 Switching Engine; Ethernet Egress Port Scheduling, Congestion Avoidance, And Marking - Cisco WS-X6066-SLB-APC - Content Switching Module Software Manual

Understanding How QoS Works
On ports configured for VLAN-based QoS, you can attach named ACLs to the port's VLAN; or for a
trunk, you can attach named ACLs to any VLANs allowed on the trunk as follows:
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On ports configured for port-based QoS, you can attach named ACLs to the port as follows:
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Final Layer 3 Switching Engine CoS and ToS Values
With a Layer 3 switching engine, QoS associates CoS and ToS values with traffic as specified by the
marking and policing rules in the ACE that the traffic matches (see the
on page
Egress Port Scheduling, Congestion Avoidance, and Marking" section on page

Classification and Marking with a Layer 2 Switching Engine

With a Layer 2 Switching Engine, QoS can classify traffic addressed to specified MAC address/VLAN
pairs to be marked with a configured CoS value (for more information, see the
page 41-2
page
Classification and marking with a Layer 2 Switching Engine uses Layer 2 CoS values. Classification
Note
and marking with a Layer 2 Switching Engine does not use or set Layer 3 IP precedence or DSCP
values.

Ethernet Egress Port Scheduling, Congestion Avoidance, and Marking

These sections describe Ethernet egress port scheduling, congestion avoidance, and marking:
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Catalyst 6000 Family Software Configuration Guide—Releases 6.3 and 6.4
41-24
On a port configured for VLAN-based QoS, traffic received through the port is compared to any
named ACLs attached to the port's VLAN. If you do not attach any named ACLs to the port's
VLAN, or if the traffic does not match an ACE in a named ACL, QoS compares the traffic received
through the port to the default ACLs.
On a trunk configured for VLAN-based QoS, traffic received through the port is compared to any
named ACLs attached to the traffic's VLAN. For traffic in VLANs that have no named ACLs
attached, or if the traffic does not match an ACE in a named ACL, QoS compares the traffic to the
default ACLs.
On a port configured for port-based QoS, traffic received through the port is compared to any named
ACLs attached to the port. If you do not attach any named ACLs to the port, or if the traffic does
not match an ACE in a named ACL, QoS compares the traffic received through the port to the
default ACLs.
On a trunk configured for port-based QoS, traffic in all VLANs received through the port is
compared to any named ACLs attached to the port. If you do not attach any named ACLs to the port,
or if the traffic does not match an ACE in a named ACL, QoS compares the traffic received through
the port to the default ACLs.
41-15). The associated CoS and ToS are used at the Ethernet egress port (see the
and the "Mapping a CoS Value to a Host Destination MAC Address/VLAN Pair" section on
41-47).
Overview, page 41-25
Transmit Queues, page 41-25
Scheduling and Congestion Avoidance, page 41-25
Marking, page 41-27
Chapter 41 Configuring QoS
"Internal DSCP Values" section
"Ethernet
41-24).
"Definitions" section on
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