Policy Events

If the POLICY_CHANGE operation type is configured to generate events, an MtxPolicyChangeEvent EDR is generated when a new policy counter is selected, a previously-selected policy counter is no longer selected, or the status of a selected policy counter has changed.

The event types for a policy change event are:
  • POLICY_SESSION_START = 28
  • POLICY_CHANGE = 29
The event indicates the session type and if the session is a 5G session:
  • SessionType
    • 1 = Sy/n40
    • 2 = Gx/n28
  • Is5G
    • true = 5G
    • false = 4G
Figure 1 shows an Sy/n40 policy session message flow and the generation of the MtxPolicyChangeEvent Event Detail Record (EDR) in this flow.
Figure 1. Policy Change Events
MATRIXX Engine sends an SNR indicating a policy change. An MtxPolicyChangeEvent is generated.

Changing the Information in Policy Change Events

For policy change EDRs (MtxPolicyChangeEvent), you can configure if all currently-selected policy counters are included in the EDR or only changed policy counters are included in the EDR. When you answer y to the following create_config.info question, only the changed policy counters are included in the change event: Global:Contain only the changed policy counters in the policy event for Sy policy?

Note: All previously-selected policy counters (LastPolicyCounterStatusList) and policy profiles (LastPolicyProfileInfoArray) are always included in the MtxPolicyChangeEvent EDR.

The following examples describe the situation when you answer n to the create_config.info question: Global:Contain only the changed policy counters in the policy event for Sy policy?

Policy Counters in Policy Change Events

Policy Counters in MtxPolicyChangeEvent shows a series of policy counter changes and the information that is included in the MtxPolicyChangeEvent EDR. Policy is configured to send all selected counters in the current counter list.

Table 1. Policy Counters in MtxPolicyChangeEvent
Step Selected Counters SLA/SNR Previous Counter List Current Counter List Notes
Sy SLR A=1, B=1 A=1, B=1 A=1, B=1
Change Detected A=1, B=2 A=1, B=2 A=1, B=1 A=1, B=2 The status of counter B is changed.
Change Detected A=1, B=2, C=1 A=1, B=2, C=1 A=1, B=2 A=1, B=2, C=1 A new policy counter C is selected.
Change Detected A=1, C=1 A=1, C=1 A=1, B=2, C=1 A=1, C=1 The previously-selected policy counter B is no longer selected.

Subscribed Policy Counters

Subscribed policy counters are policy counters that the PCRF subscribes to by including a list of policy counter IDs in an Sy SLR message. If subscribed policy counters are in an Sy SLR message, MATRIXX Engine only returns those policy counters in subsequent Sy messages, and only includes those policy counters in policy change events for both previous and current policy counter lists. Otherwise, all selected policy counters are returned in Sy messages and are included in policy change events.

If a subscribed counter is not selected by the engine, an unknown policy counter status that is defined during configuration is used as the status for the counter in returned Sy messages and in policy change events. The default value (UnknownCounter) for an unknown policy counter status is used if there is no configured unknown policy counter status.

In Subscribed Policy Counters, there is an initial Sy SLR request with counter A and counter B. The unknown policy counter status is configured as "Unknown". Policy is configured to send all currently-selected counters in the current counter list.

Table 2. Subscribed Policy Counters
Steps Subscribed Counters Selected Counters SLA/SNR Previous Counter List Current Counter List Notes
Sy SLR A, B A=1, B=1, C=1 A=1, B=1 N/A A=1, B=1 Counter C is selected but not subscribed. It is not returned in the Sy SLA message and not in the policy change event.
Change Detected A, B A=1, B=1, C=2 N/A N/A N/A The status of counter C is changed. Because it is not subscribed, there is no SNR message and no policy change event.
Change Detected A, B A=1, C=2 A=1, B=Unknown A=1, B=1 A=1, B=Unknown Counter B becomes unknown.
Change Detected A, B A=2, C=2 A=2, B=Unknown A=1, B=Unknown A=2, B=Unknown The status of counter A changes.

Send Only Changed Counters

If a previously-selected counter is no longer selected, the counter is sent with one of the following values:
  • If StatusIfNotPresent is defined in My MATRIXX, the value of this field is used as the status for the counter in returned SNR messages and in the counter list in the MtxPolicyChangeEvent EDR.
  • If StatusIfNotPresent is not defined, the unknown policy counter status definition is used. If you do not define a value for unknown status, the default value UnknownCounter is used.

In Send Only Changed Counters, the UnknownCounter status is used and the SNR message is configured to only include changed counters. Policy is configured to send changed counters in the current counter list.

Table 3. Send Only Changed Counters
Steps Subscribed Counters Selected Counters SLA/SNR Previous Counter List Current Counter List Notes
Sy SLR - A=1, B=1 A=1, B=1 N/A A=1, B=1
Something changes - A=1, B=2 B=2 A=1, B=1 B=2 Only the changed counter B is in the SNR and in the current policy counter list in the policy change event.
Something changes - A=1 B=UnknownCounter A=1, B=2 B=UnknownCounter Only the uninstalled counter B is in the SNR and in the current policy counter list in the policy change event.
Something changes - A=2 A=2 A=1 A=2

Pending Policy Activation

In Pending Policy Activation when pending policies become active, an MtxPolicyChangeEvent EDR is generated. The EDR includes the current state of the counters and the changed counter values that were previously sent in the Sy SLA and SNR that are now active.
Table 4. Pending Policy Activation
Steps Subscribed Counters Selected Counters SLA/SNR Previous Counter List Current Counter List
Sy SLR N/A A=1, B=1

Pending: A=1, B=2

 A=1, B=1

Pending: A=1, B=2

 N/A A=1, B=1
Pending Policies Become Active N/A A=1, B=2 A=1, B=2 A=1, B=1 A=1, B=2
Change Detected N/A A=1, B=2

Pending: A=1

 N/A N/A N/A
Pending Policies Become Active N/A A=1 A=1 A=1, B=2 A=1