Cisco 10000 Series User Manual

10-6
Cisco 10000 Series Router Quality of Service Configuration Guide
OL-7433-09
Chapter 10 Overhead Accounting
Overhead Accounting and Hierarchical Policies
Overhead Accounting and Hierarchical Policies
In hierarchical policies, you can enable overhead accounting for shaping and bandwidth on top-level
parent policies, middle-level child policies, and bottom-level child policies. If you enable overhead
accounting on a:
• Parent class-default class, you are not required to enable accounting on a child traffic class that does
not contain the bandwidth or shape command.
• Child policy, then you must enable overhead accounting on the parent policy.
The parent and child classes must specify the same encapsulation type when enabling overhead
accounting and configuring an offset using the user-defined offset [atm] command option.
Table 10-2 summarizes the configuration requirements for overhead accounting. For example, if
overhead accounting is currently enabled for a parent policy, then accounting can be disabled or enabled
on a child policy.
AAL5 MUX plus PPPoA 10 8-byte AAL5 trailer + 2-byte protocol ID (0x0021)
AAL5 SNAP plus 1483 18 8-byte AAL5 trailer + 3-byte LLC header
(0xAAAA03) + 3-byte OUI (0x0080c2) + 2-byte
protocol ID (0x0007) + 2-byte PAD (0x0000)
AAL5 SNAP plus PPPoA 12 8-byte AAL5 trailer + 3-byte LLC header (0xFEFE03)
+ 1-byte protocol ID (0xCF)
PPPoE 6 1-byte version/type (0x11) + 1-byte code (0x00) +
2-byte session ID + 2-byte length
qinq 22 6-byte destination MAC address + 6-byte source MAC
address + 2-byte protocol ID (0x8100) + 2-byte
VID/CFI/PRIORITY + 2-byte protocol ID + 2-byte
inner tag + 2-byte length or type
Table 10-1 Overhead Calculation (continued)
Encapsulation Type Number of Bytes Description
Ta b l e 10-2 Overhead Accounting Configuration Requirements
Policy Map or Class Current Configuration Configuration Requirement
Parent Enabled Enabled on child policy
Child Enabled Enabled on parent policy
Child class Enabled Enabled on all classes in the child policy map,
except priority classes with policing
Child class (nonpriority
without policing)
Disabled Disabled on all classes in the child policy map
Child class (priority with
policing)
Disabled Disabled or enabled on all nonpriority classes
in the child policy map

Cisco 10000 Series Specifications

General

Brand	Cisco
Model	10000 Series
Category	Network Router
Language	English