Cisco ASR 5000 Series Administration Manual page 31

Enhanced Charging Service Overview
In the chassis/PCEF, the Service Group QOS feature enables to:
 Define service-groups that may include unrelated services defined on the chassis/PCEF.
 Dynamically install pre-defined service-groups for a subscriber over Gx.
 Dynamically remove pre-defined service-groups for a subscriber over Gx.
 Dynamically set and change QoS parameters of a service-group for a subscriber over Gx using CCA and RAR
messages. QoS parameters of a service-group (FUP-QoS) are:
 Flow-Rate
 Flow-Status
 Volume Threshold
 Apply Flow-Status to a packet-flow progressively at service and service-group levels. The rules for hierarchical
enforcement of Flow-Status rule are:
 Flow-Status Gating at Service Level: If rule indicates "block" or "redirect", then that action is taken. If
 Flow-Status Gating at Service-Group Level: If rule indicates "block" or "redirect", then that action is
 Apply Flow-Rate to a packet-flow progressively at service and service-group levels. Maximum Bit-rate and
Burst size is defined by Flow-Rate. Meter the traffic to the configured Flow-Rate and based on the output,
apply DSCP marking to the packet.
The rules of hierarchical QOS enforcement are:
 Metering at Service Level: Initially, traffic is metered against service-level QOS rule. If the result of
 Metering at Service-Group Level: If the packet is allowed at service level, then service-group level
 Monitor volume usage of a group-of-services. Multiple group-of-services can share a volume-quota.
 Provide a mechanism to share configured volume threshold of a service-group across all services in that group.
This sharing would be dynamic, that is no predefined quota is allocated per service in a service group.
 Generate a notification to PCRF in a CCR-U message, when volume threshold for a group-of-services is crossed.
Once a notification is generated, the trigger is disarmed to generate notification. Continue to monitor usage, but
do not report further breaches until PCRF explicitly enables threshold-breach notification trigger in a CCA-U
message.
 Report volume usage to PCRF in a CCR-U message when the service-group removed is the last using the shared
volume-quota.
rule indicates "allow", then next level's gating rule is applied.
taken. If rule indicates "allow", then next level's gating rule is applied.
Important:
The output action of Flow-Rate can be forward, drop, or mark DSCP. Flow-Rate
may allow the packet without DSCP marking.
metering marks or drops the packet, then the next level metering is not performed.
QOS metering is done. If the result of metering marks or drops the packet, then the next level
metering is not performed.
Important:
The packet is first subjected to Flow-Status enforcement and if allowed by Flow-
Status only then Flow-Rate is enforced. Flow-Status enforcement includes applying Flow-Status
progressively at service and service-group Levels. If the flow-status at both levels allows the packet
to pass only then it is given for flow-rate enforcement, which applies Flow-Rate progressively at
service and service-group levels.
Cisco ASR 5x00 Enhanced Charging Services Administration Guide ▄
Enhanced Features and Functionality ▀
31