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Cisco 10000 Series Router Quality of Service Configuration Guide
OL-7433-09
Chapter 4 Attaching Service Policies
Attaching Layer 2 Access Concentrator QoS Service Policies
Attaching Layer 2 Access Concentrator QoS Service Policies
You can attach a QoS service policy to an ATM VC on the Layer 2 access concentrator (LAC) using the
service-policy
command.
This section describes the following topics:
•
Feature History for LAC QoS, page 4-30
•
LAC QoS Inheritance, page 4-30
•
Restrictions and Limitations for Attaching LAC QoS, page 4-31
•
Attaching QoS Policies to LAC ATM Virtual Circuits, page 4-31
Feature History for LAC QoS
LAC QoS Inheritance
The following describes how LAC traffic inherits QoS policies:
•
If you attach a service policy only to the physical ATM interface, the aggregate of all
unshaped
UBR
PVCs is subject to the physical interface’s service policy. The router treats shaped UBR PVCs like
variable bit rate (VBR) and constant bit rate (CBR) PVCs.
•
If you attach a service policy only to individual ATM PVCs and not to the physical ATM interface,
only the individual PVC is subject to its attached service policy.
•
If you attach service policies to both the physical ATM interface and individual ATM PVCs, the
aggregate of all UBR PVCs without an attached service policy is subject to the physical interface’s
service policy. All PVCs with an attached service policy are individually subject to their attached
service policies.
When a service policy is attached to an individual ATM PVC, sessions that use that PVC inherit the
service policy applied to the PVC or the inherited policy of the PVC. If a session inherits a policy, the
show policy interface virtual access
command does not display the state of the inherited policy. You
can display the state of the policy only on the interface where you configured the policy. If you attach a
service policy only to:
•
The physical Ethernet interface, the aggregate of all of the VLAN subinterfaces is subject to the
physical interface’s service policy.
•
Individual VLAN subinterfaces, and not to the physical Ethernet interface, only the individual
VLAN subinterfaces are subject to the attached service policies.
Cisco IOS Release
Description
Required PRE
12.3(7)XI3
The QoS: Broadband Aggregation Enhancements - Phase 1
feature (also known as LAC QoS) was introduced on the
router to support LAC QoS policies on an ATM virtual
circuit.
PRE2
12.2(28)SB
LAC QoS was integrated in Cisco IOS
Release 12.2(28)SB.
PRE2