Cisco Systems EA6500 Manual De Usuario

The PFC does not provide QoS for FlexWAN module ports. Refer to the following publications for 
information about FlexWAN module QoS features:

Cisco IOS Quality of Service Solutions Configuration Guide, Release 12.1:

Cisco IOS Quality of Service Solutions Command Reference, Release 12.1:

Class-Based Marking:

Traffic Policing:

Distributed Class-Based Weighted Fair Queueing and Distributed Weighted Random Early 
Detection:

Distributed Low Latency Queueing:

Configuring Burst Size in Low Latency Queueing:

Distributed Traffic Shaping:

MPLS QoS:

This section defines some QoS terminology:

Packets carry traffic at Layer 3.

Frames carry traffic at Layer 2. Layer 2 frames carry Layer 3 packets.

Labels are prioritization values carried in Layer 3 packets and Layer 2 frames:

Layer 2 class of service (CoS) values, which range between zero for low priority and seven for 
high priority:

Layer 2 Inter-Switch Link (ISL) frame headers have a 1-byte User field that carries an IEEE 
802.1p CoS value in the three least significant bits.

Layer 2 802.1Q frame headers have a 2-byte Tag Control Information field that carries the CoS 
value in the three most significant bits, which are called the User Priority bits.

Other frame types cannot carry Layer 2 CoS values.