Rate-limiting action (ingress, egress)

Rate-limiting action is implemented via policers. The policer is dynamically created at the PCC rule instantiation time. The rate can be enforced based on Layer 2 rates or Layer 3 rates.

Dynamically instantiated policers have their own policer ID range to avoid the conflict with static policers.

The dynamically created policers shares common properties configured under the dynamic-policer CLI hierarchy:

configure
   qos
      sap-ingress/egress
         dynamic-policer  
            stat-mode <stat_mode>
            parent <arbiter-name> [weight <weight-level>] [level <level>
            mbs <size> [bytes | kilobytes]
            cbs  <size> [bytes | kilobytes]
            packet-byte-offset {add <add-bytes> | subtract <sub-bytes>}
            range start-entry <entry-id> count <count>

The configured dynamic policer parameters can be overridden per PCC rule by including the Alc-Dynamic-Policer grouped AVP in the QoS-Information AVP. All AVPs are optional and when specified override the configured value:

• ingress PCC rules

  +--1046 Alc-Dynamic-Policer
     +--1039 Alc-Policer-Parent
        +--1022 Alc-Arbiter-Name
        +--1040 Alc-Parent-Level
        +--1041 Alc-Parent-Weight
     +--1008 Alc-Committed-Burst-Size-UL
     +--1009 Alc-Maximum-Burst-Size-UL
     +--1042 Alc-Stat-Mode-UL
     +--1044 Alc-Packet-Byte-Offset-UL
  

• egress PCC rules

  +--1046 Alc-Dynamic-Policer
     +--1039 Alc-Policer-Parent
        +--1022 Alc-Arbiter-Name
        +--1040 Alc-Parent-Level
        +--1041 Alc-Parent-Weight
     +--1010 Alc-Committed-Burst-Size-DL
     +--1011 Alc-Maximum-Burst-Size-DL
     +--1043 Alc-Stat-Mode-DL
     +--1045 Alc-Packet-Byte-Offset-DL
  

The policer rates are part of PCC rule itself and are not part of static configuration.

The generic Gx directive for rate-limiting action is:

Charging-Rule-Install ::=      <AVP Header: 1001>
     Charging-Rule-Definition <AVP Header: 1003>
          Charging-Rule-Name <AVP Header: 1005> 
          QoS-Information <AVP Header: 1016>                         
               Max-Requested-Bandwidth-UL <AVP Header: 516> [bps] 3GPP 29.214 §5.3.15
        Max-Requested-Bandwidth-DL <AVP Header: 515> [bps] 3GPP 29.214 §5.3.14
        Guaranteed-Bitrate-UL <AVP Header: 1026> [bps] 3GPP 29.214 §5.3.26
        Guaranteed-Bitrate-DL <AVP Header: 1027> [bps] 3GPP 29.214 §5.3.25

The above rate limits refer to PIR and CIR rates of the dynamic policer in the respective direction.