Accounting modes of operation

This section is applicable to the 7750 SR or the 7450 ESS. There are three basic accounting models:

Each of the basic models can optionally be enabled to send interim-updates. Inclusion/exclusion of interim-updates depends on whether volume based (start/interim-updates/stop) or time-based (start/stop) accounting is required.

The difference between the three basic accounting models is in its core related to the processing of the acc-session-id for each model. The differences are related to:

The counters for volume-based accounting are collected from queues or policers that are instantiated per SLA profile instance (SPI). This is true regardless of which model of accounting (or combination of models) is deployed. Within the accounting context, the SPI equates to queue-instance.

The following table summarizes the key differences between various accounting modes of operation that are supported. Interim-updates for each individual mode can be enabled or disabled through configuration (keyword as an extension to the commands that enable three basic modes of accounting). This is denoted by the IU-Config keyword under the ‛I-U’ column in the table. The table also shows that any two combinations of the three basic models (including their variants for volume and time- based accounting) can be enabled simultaneously.

Table: Accounting modes of operation
Accounting mode Accounting entity START I-U STOP Acct-session-id Acct-multi-session-id

queue-instance-accounting

queue-instance

X

IU-config

X

X

session

host

session-accounting

queue-instance

session

X

IU-config

X

X

queue-instance

host

host-accounting

queue-instance

session

host

X

IU-config

X

X

queue-instance

queue-instance-accounting + host-accounting

queue-instance

X

IU-config

X

X

queue-instance

session

host

X

IU-config

X

X

queue-instance

queue-instance-accounting + session-accounting

queue-instance

X

IU-config

X

X

queue-instance

session

X

IU-config

X

X

queue-instance

host

session-accounting + host-accounting

queue-instance

session

X

IU-config

X

X

queue-instance

host

X

IU-config

X

X

session

Note: Hosts within the targeted CoA entity are affected as follows:

The same principle applies to LI.

The accounting behavior (accounting messages and accounting attributes) in case that the SPI is changed with CoA depends on the accounting mode of operation. The behavior is the following: