22-3
Cisco 10000 Series Router Quality of Service Configuration Guide
OL-7433-09
Chapter 22 Hierarchical Scheduling and Queuing
Hierarchical Queuing Framework
QoS Shaping Using HQF
The PRE3 and PRE4 support QoS shaping using the HQF algorithm. The following sections describe
how the HQF is used to provide shaping for various QoS models:
•
ATM Virtual Path Shaping Using HQF, page 22-3
•
ATM VC Shaping Using HQF, page 22-3
•
Hierarchical ATM VP and VC Shaping Using HQF, page 22-4
•
Subinterface Shaping Using HQF, page 22-4
•
IP and PPP Session Shaping Using HQF, page 22-5
ATM Virtual Path Shaping Using HQF
A permanent virtual path (PVP) is used to multiplex one or more virtual circuits (VCs). To create a PVP,
use the
atm pvp
command in interface configuration mode:
atm pvp
vpi
peak-rate
[
no-f4-oam
]
The HQF algorithm treats ATM virtual paths (VPs) as physical interfaces and uses the peak rate you
specify to shape bandwidth. The ATM segmentation and reassembly (SAR) mechanism is configured the
same as on the PRE2.
The following example shows how to create a PVP with a peak rate of 50,000 kbps:
interface atm 7/0/0
atm pvp 25 50000
ATM VC Shaping Using HQF
HQF treats ATM VCs created on the physical interface as logical interfaces and the ATM port as the
physical layer. The PRE3 and PRE4 do not support ATM SAR-based VC shaping.
The following examples show how to configure ATM VC shaping for the PRE3 and PRE4. The
configuration creates a variable bit rate-nonreal-time (VBR-nrt) VC on the physical ATM interface with
a service policy applied to it. HQF shapes the VC traffic according to the sustained cell rate (SCR) of
the VC (512 kbps). The service policy applied to the interface creates two separate class queues on the
VC: real-time and class-default.
policy-map pppoe_vc_out
class real-time
police percent 10 200 ms 100 ms conform-action transmit exceed-action drop
violate-action drop
priority
class class-default
random-detect aggregate
random-detect precedence values 0 minimum-thresh 10 maximum-thresh 20 mark-prob 10
random-detect precedence values 1 minimum-thresh 40 maximum-thresh 80 mark-prob 10
interface ATM 1/0/0.1 point-to-point
pvc 0/110
vbr-nrt 512 512 94
encapsulation aal5autoppp Virtual-Template1
service-policy output pppoe_vc_out