Pfc Qos Feature Flowcharts - Cisco 6500 Series Software Configuration Manual

Understanding How PFC QoS Works

PFC QoS Feature Flowcharts

Figure 31-1
Figure 31-1 Traffic Flow Through PFC QoS Features with PFC2
Frame enters
OSM traffic
enters switch
PFC QoS supports traffic from OSMs with Release 12.1(11a)E and later.
Note
Figure 31-2 Traffic Flow Through PFC QoS Features with PFC
Frame enters
Note •
•
•
Figure 31-3
components.
Catalyst 6500 Series Switch Cisco IOS Software Configuration Guide—Release 12.1 E
31-6
show how traffic flows through the components that support PFC QoS features.
Ethernet
LAN
switch
ingress port
OSM
ingress
port
CoS = 0 for all ATM and POS traffic
(not configurable)
Ethernet
ingress
switch
port
The PFC can provide Layer 3 switching for FlexWAN traffic but does not provide PFC QoS for
FlexWAN traffic.
PFC QoS does not change the ToS byte in FlexWAN ingress traffic.
Traffic that is Layer 3-switched does not go through the MSFC and retains the Layer 2 CoS value
assigned by the PFC.
through Figure 31-8
Policy Feature Card 2
(PFC2)
QoS features
OSM OSM
ingress QoS egress QoS
features features
Policy Feature
Card (PFC)
show how the PFC QoS features are implemented on the switch
Chapter 31 Configuring PFC QoS
Ethernet
Transmit
egress
frame
port
CoS = IP precedence
for all traffic
(not configurable)
Multilayer Switch
Feature Card 2
(MSFC2)
OSM
egress
port
Ethernet
Transmit
egress
frame
port
CoS = 0 for all traffic
(not configurable)
Multilayer Switch
Feature Card (MSFC)
FlexWAN
interfaces
Transmit
OSM traffic
FlexWAN
interfaces
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