Hierarchical Enforcement Of Qos Parameters - Cisco ASR 5000 Series Administration Manual

▀ Enhanced Features and Functionality
configure service-level volume quota, you can configure the same monitoring-key for all ruledefs that share the
same charging action. Monitoring-Key mechanism enables setting and changing Volume-threshold over Gx.
In ECS, changing QoS parameters at a service level means changing parameters of a charging-action.
ECS supports three different kinds of ruledefs:
 Static rules that are defined in the CLI, and are active immediately after they are defined.
 Pre-defined rules that are defined in the CLI and activated/deactivated over Gx.
 Dynamic rules which are defined, activated and deactivated over Gx.
For static and predefined rules, ECS supports updating per-subscriber FUP parameters of a charging-action
over Gx. This is achieved using the Charging-Action-Install AVP. Changes to FUP-parameters of dynamic
rules are done using the 3GPP-standard Charging-Rule-Definition AVP.

Hierarchical Enforcement of QoS Parameters

When a packet arrives, ECS performs Deep Packet Inspection and rule matching. If the packet matches a rule, Control-
Charge processing is performed as defined by the matched rule. Ruledef-level and QoS-group-of-ruledefs level QoS
enforcement are performed as part of Control-Charge processing.
It is not mandatory to set QoS parameters for a ruledef over Gx. If QoS parameters are not set over Gx, then static
definition, if any, is enforced. Similarly, for a subscriber session it is not mandatory to group ruledefs in one or more
QoS-group-of-ruledefs. A subscriber may not have any QoS-group-of-ruledefs configured. Incoming traffic may match
a ruledef, which has no associated QoS-group-of-ruledef for that subscriber session. In that case, action is taken based
only on the configuration for that ruledef.
Applying Flow-Status
Flow-Status is applied in a hierarchical manner with the following precedence:
1. Flow Gating at charging-action Level: If flow-action in charging rule indicates "block" or "redirect", then that
action is taken. If rule indicates "allow", then next level's gating rule is applied.
2. Flow Gating at QoS-Group-of-Ruledefs Level: Flow-Status specified for the matched QoS-group-of-ruledefs is
applied.
Applying Flow-Rate
Hierarchy of metering and marking packet follows the precedence:
1. Metering at Charging-Action Level: Flow-Rate at ruledef level is specified in the charging-action associated
with the ruledef. Bandwidth metering specified for the charging-action is first applied to every packet. If the
packet conforms to specified bandwidth limits, then QoS-group-of-ruledefs level metering will be performed.
If the packet exceeds bandwidth limit at charging-action, then specified exceed action will be taken and
bandwidth metering at QoS-group-of-ruledefs and subscriber level will not be performed.
2. Metering at QoS-Group-of-Ruledefs Level: If a packet conforms to charging-action bandwidth limits, then QoS-
group-of-ruledefs level bandwidth metering will be done. If the packet conforms to specified bandwidth limits,
then subscriber-level metering will be performed. If the packet exceeds bandwidth limit at QoS-group, then
specified exceed action will be taken.
Monitoring Usage and Reporting Threshold Breaches
Volume usage is tracked at the charging-action level and at QoS-group-of-ruledefs level. If a received packet causes
volume threshold to exceed, then a trigger ECS sends a CCR-U message to PCRF with Service-Group-Event AVP
▄ Cisco ASR 5x00 Enhanced Charging Services Administration Guide
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Enhanced Charging Service Overview