Cisco ASR 901 Command Reference Manual page 159

Chapter 1 CLI Command Reference
Command History Release
15.1(2)SNG
Usage Guidelines
The measurement interval is the committed burst size (Bc) divided by committed information rate (CIR).
Bc cannot be set to 0. If the measurement interval is too large (greater than 128 milliseconds), the system
subdivides it into smaller intervals.
If you do not specify the committed burst size (Bc) and the excess burst size (Be), the algorithm decides
the default values for the shape entity. The algorithm uses a 4 milliseconds measurement interval, so Bc
is CIR * (4 / 1000).
Burst sizes larger than the default committed burst size (Bc) need to be explicitly specified. The larger
the Bc, the longer the measurement interval. A long measurement interval may affect voice traffic
latency, if applicable.
When the excess burst size (Be) is not configured, the default value is equal to the committed burst size
(Bc).
Examples The following example configures a shape entity with a CIR of 1 Mbps and attaches the policy map
called dts-interface-all-action to interface pos1/0/0:
policy-map dts-interface-all-action
class class-interface-all
shape average 1000000
interface pos1/0/0
service-policy output dts-interface-all-action
Traffic Shaping Overhead Accounting for ATM
When a parent policy has ATM overhead accounting enabled for shaping, you are not required to enable
accounting at the child level using the police command. In the following configuration example, ATM
overhead accounting is enabled for bandwidth on the gaming and class-default class of the child policy
map named subscriber_classes and on the class-default class of the parent policy map named
subscriber_line. The voip and video classes do not have ATM overhead accounting explicitly enabled.
These priority classes have ATM overhead accounting implicitly enabled because the parent policy has
ATM overhead accounting enabled. Notice that the features in the parent and child policies use the same
encapsulation type.
policy-map subscriber_classes
class voip
priority level 1
police 8000
class video
priority level 2
police 20
class gaming
bandwidth remaining percent 80 account aal5 snap-rbe-dot1q
class class-default
bandwidth remaining percent 20 account aal5 snap-rbe-dot1q
policy-map subscriber_line
class class-default
bandwidth remaining ratio 10 account aal5 snap-rbe-dot1q
shape average 512 account aal5 snap-rbe-dot1q
service policy subscriber_classes
OL-26031-07
Modification
Support for this command was introduced on the Cisco ASR 901 router.
Cisco ASR 901 Aggregation Services Router Command Reference Guide
shape (policy-map class)
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