2.5 Triggers

An execution trigger defines a Triggering Point within the message processing logic. When the triggering point is reached, the mediation operations (Rule Sets) associated with that triggering point are executed. The type of the Trigger defines whether the triggering point is part of the request or the answer processing. The Rule Set can be defined to be executed as a part of the Actions of another Rule Set, or it can be triggered at some specific point of the message processing. A Trigger is executed during an ingress and egress message.

Associations of a Trigger with new Rule Sets can be added, existing associations can be removed, and the sequence of the Rule Set Name list can be changed to modify the dra-Worker behavior based on the Rule Set execution. The behavior of an dra-Worker is the same with and without a Trigger if no Rule Set is associated with the Trigger.

Rule Sets associated with a Trigger are executed in the sequence in which they are listed under the Trigger name on the Diameter, and then Mediation, and then Triggers page.

A Trigger is created by setting a specific point at the Diameter Routing Layer (DRL), Diameter Connection Layer (DCL) or Diameter Application Layer (DAL).

Diameter Routing Layer (DRL) Triggers

Diameter Routing Layer (DRL) Triggers, which enable request and answer messaging using RTP1, RTP10, ATP1, ATP10 and RTP11 trigger points. The Triggers described in Diameter Routing Layer (DRL) Triggers are available for Diameter Mediation. Table 2-25 lists the routing layer execution trigger names and related information.

Table 2-25 Diameter Mediation Routing Layer Triggers

Execution Trigger Name Message Type Triggering Point
Diameter request message received from connection Request Request Trigger Point 1; occurs upon receipt of a request (RTP1)
Diameter request message ready to be forwarded to connection Request Request Trigger Point 10; occurs just before forwarding the request upstream (RTP10)
Diameter answer message received from connection Response Answer Trigger Point 1; occurs upon receipt of an answer (ATP1)
Diameter answer message ready to be forwarded to connection Response Answer Trigger Point 10; occurs just before forwarding the answer downstream (ATP10)
Diameter request message attempted for re-route Request Request Trigger Point 11 (RTP11); occurs just prior to re-routing the request upstream.

Diameter Connection Layer (DCL)

Diameter Connection Layer (DCL) Triggers enable peer-to-peer messaging using CEx, DWx, DPx trigger points.

The data stored as an Internal Variable or a linking AVP at one of the DCL triggers is valid only inside of the current trigger and can not be accessed by other triggers. The Triggers described in Diameter Mediation Connection Triggers are available for Diameter Mediation.

Table 2-26 lists the connection layer execution trigger names and related information.

Table 2-26 Diameter Mediation Connection Layer Triggers

Execution Trigger Name Message Type Triggering Point
CER message received from connection Request Capabilities - Exchange-Request Trigger Point 1; occurs upon receipt of a CER message (CER1)
CER message ready to be sent Request Capabilities - Exchange-Request Trigger Point 10; occurs just prior to sending the CER message (CER10)
CEA message received from connection Response Capabilities - Exchange-Answer Trigger Point 1; occurs upon receipt of a CEA message (CEA1)
CEA message ready to be sent Response Capabilities - Exchange-Answer Trigger Point 10; occurs just prior to sending the CEA message(CEA10)
DWR message received from connection Request Device-Watchdog-Request Trigger Point 1; occurs upon receipt of a DWR message (DWR1)
DWR message ready to be sent Request Device-Watchdog-Request Trigger Point 10; occurs just prior to sending the DWR message (DWR10)
DWA message received from connection Response Device-Watchdog-Answer Trigger Point 1; occurs upon receipt of a DWA message (DWA1)
DWA message ready to be sent Response Device-Watchdog-Answer Trigger Point 10; occurs just prior to sending the DWA message (DWA10)
DPR message received from connection Request Disconnect-Peer-Request Trigger Point 1; occurs upon receipt of a DPR message (DPR1)
DPR message ready to be sent Request Disconnect-Peer-Request Trigger Point 10; occurs just prior to sending the DPR message (DPR10)
DPA message received from connection Response Disconnect-Peer-Answer Trigger Point 1; occurs upon receipt of a DPA message (DPA1)
DPA message ready to be sent Response Disconnect-Peer-Answer Trigger Point 10; occurs just prior to sending the DPA message(DPA10)

Diameter Application Layer (DAL)

Diameter Application Layer (DAL) Triggers can modify the requests and answers based on the condition of the message forwarded to an application or in case the message exits an application. The application can be verified before the template or rule set's execution when the trigger points are assigned. The Diameter, and then Mediation, and then Triggers [Insert] page provides an association between the template (rule set) and the application, with the options to:
  • Execute the template (rule set), if the involved application is name of the application.
  • Execute the template (rule set) unconditionally, in other words, for all involved applications.
The Triggers described in Diameter Mediation Application Triggers are available for Diameter Mediation. Table 2-27 lists the application trigger names and related information.

Table 2-27 Diameter Mediation Application Triggers

Execution Trigger Name Message Type Triggering Point
Diameter request message ready to be forwarded to application Request Request Trigger Point 4; occurs just prior to the invocation of an application (RTP4)
Diameter request message received from application Request Request Trigger Point 6; occurs immediately after exiting an application (RTP6)
Diameter answer message ready to be forwarded to application Response Answer Trigger Point 4; occurs just prior to the invocation of an application (ATP4)
Diameter answer message received from application Response Answer Trigger Point 6; occurs immediately after exiting an application (ATP6)
Templates are not executed if:
  • A template (rule set) is assigned to a specific application and the application is disabled, the associated templates (rule sets) are not executed.
  • An application generates an Answer, templates at RTP6 and ATP4 are not executed.
  • An application generates a Request, templates at RTP4 and ATP6 are not executed.
  • An application does not stay in the loop for answer processing, templates at ATP4 or ATP6 are not executed.
Rule Sets associated with a Trigger are executed in the sequence in which they are listed under the Trigger name and you can perform the following actions: