Cisco Systems OL-4266-08 manual 2shows traffic flow and PFC QoS features with a PFC3, 42-4

Chapter 42 Configuring PFC QoS

Understanding How PFC QoS Works

These figures provide more detail about the relationship between QoS and the router components:

•Figure 42-2,Traffic Flow and PFC QoS Features with PFC3

•Figure 42-3,Traffic Flow and PFC QoS Features with PFC2

•Figure 42-4,PFC QoS Features and Component Overview

Figure 42-2shows traffic flow and PFC QoS features with a PFC3.

Figure 42-2 Traffic Flow and PFC QoS Features with PFC3

FlexWAN traffic	FlexWAN	Multilayer Switch		FlexWAN	Transmit
	ingress port and	Feature Card	egress port and
					FlexWAN traffic
enters switch
	QoS features	(MSFC)	QoS features
				CoS = IP precedence for all traffic
				(not configurable)

LAN traffic enters switch

OSM traffic

enters switch

LAN ingress port and QoS features

OSM ingress port and QoS freatures

Ingress

PFC3

QoS

PFC3

Layer 2 or 3

switching

Egress

PFC3

QoS

LAN egress port and QoS features

OSM egress port and QoS freatures

Transmit

LAN traffic

Transmit

OSM traffic

105757

CoS = 0 for all ATM and POS traffic (not configurable)

Figure 42-2shows how traffic flows through the PFC QoS features with PFC3:

•Traffic can enter on any type of port and exit on any type of port.

•DFCs implement PFC QoS locally on switching modules.

•For FlexWAN module traffic:

–Ingress FlexWAN QoS features can be applied to FlexWAN ingress traffic.

–Ingress FlexWAN traffic can be Layer 3-switched by the PFC3 or routed in software by the MSFC.

–Egress PFC QoS is not applied to FlexWAN ingress traffic.

–Egress FlexWAN QoS can be applied to FlexWAN egress traffic.

•For LAN-port traffic:

–Ingress LAN-port QoS features can be applied to LAN-port ingress traffic.

–Ingress PFC QoS can be applied to LAN-port ingress traffic.

–Ingress LAN-port traffic can be Layer-2 or Layer-3 switched by the PFC3 or routed in software by the MSFC.

–Egress PFC QoS and egress LAN-port QoS can be applied to LAN-port egress traffic.

•For OSM traffic:

–Ingress OSM-port QoS features can be applied to OSM-port ingress traffic.

–Ingress PFC3 QoS can be applied to OSM-port ingress traffic.

–Ingress OSM-port traffic can be Layer-3 switched by the PFC3 or routed in software by the MSFC.

–Egress PFC3 QoS and egress OSM-port QoS can be applied to OSM-port egress traffic.

Cisco 7600 Series Router Cisco IOS Software Configuration Guide, Release 12.2SX

42-4 OL-4266-08