Forwarding-class change (ingress, egress)

Traffic can be re-prioritized via PCC rule by re-classification into a different forwarding class. The forwarding-class can be changed in several cases.

The original static mapping between traffic type, forwarding-class and the queue/policer in the base qos-policy is configured outside of the ip-criteria CLI hierarchy.

For example:

     config>qos>sap-egress#
          dscp af11 fc "af"

Such mapping is configured outside of CAM and therefore it has lower evaluation priority than the mapping configured via PCC rule which is installed in CAM.

The original static mapping is provisioned in the base qos-policy via ip-criteria CLI hierarchy.

For example:

     config>qos>sap-egress># 
           ip-criteria
                entry 40000 create
                     match 
                          dscp af11
                 exit
         action fc "af"
    exit
   exit

Then, the configured entry range for PCC rules must precede the static entry (match criteria) in which the original forwarding-class is configured. The insertion point (entry) is controlled via configuration: sub-insert-shared-pccrule start-entry <entry-id> count <count> command under the qos-policy.

In both of the above cases, the following PCC rule would override forwarding-class for traffic with DSCP value of 10 (af11 traffic class) from value af to h2.

Charging-Rule-Install 
     Charging-Rule-Definition 
          Charging-Rule-Name = fc-change
          Flow-Information
               ToS-Traffic-Class = 00101000 11111100
               Flow-Direction = 1
          QoS-Information      
               QoS-Class-Identifier  = 2   

The eight forwarding classes are mapped to QCIs (3GPP TS 23.203 §6.1.7.2) in the manner displayed in Table: Forwarding class and QCI mapping.

The generic Gx directive for forwarding-class change:

Charging-Rule-Install ::=      <AVP Header: 1001>
     Charging-Rule-Definition <AVP Header: 1003>
          Charging-Rule-Name <AVP Header: 1005>      
               QoS-Information <AVP Header: 1016>              3GPP 29.212 §5.3.16
                    QoS-Class-Identifier <AVP Header: 1028>     3GPP 29.212 §5.3.17