Identification of timestamps for a partial CDR when failover occurs in an offline charging system

1. An Offline Charging System (OFCS) comprising:

a remediation system configured to generate a next partial Charging Data Record (CDR) for a session after charging is handed over from a primary charging function of the OFCS to a secondary charging function of the OFCS, wherein the remediation system is configured to generate the next partial CDR instead of the secondary charging function;

the remediation system comprising:

an interface configured to receive an interim accounting request for the session from the secondary charging function after charging is handed over from the primary charging function to the secondary charging function; and

a controller configured to open the next partial CDR for the session based on the interim accounting request;

the interface is configured to receive a prior partial CDR for the session from the primary charging function;

the controller is configured to parse the prior partial CDR to identify a CDR timestamp, and to record a start time in the next partial CDR based on the CDR timestamp;

the controller is configured to parse the interim accounting request to identify an accounting timestamp for the session, to record an end time in the next partial CDR based on the accounting timestamp, to close the next partial CDR, and to transmit the next partial CDR to a billing domain.

2. The OFCS of claim 1 further comprising:

the secondary charging function, responsive to detecting handover of charging for the session from the primary charging function, is configured to identify the remediation system, and to route the interim accounting request to the remediation system.

3. The OFCS of claim 1 wherein:

the prior partial CDR includes multiple timestamps; and

the controller is configured to select one of the multiple timestamps that is associated with closure of the prior partial CDR as the CDR timestamp.

4. The OFCS of claim 1 further comprising:

the primary charging function is configured to store the prior partial CDR in memory;

the primary charging function, responsive to detecting handover of charging for the session to the secondary charging function, is configured to identify the remediation system, and to route the prior partial CDR to the remediation system.

5. The OFCS of claim 1 wherein:

the interim accounting request comprises a Diameter request; and

the controller is configured to identify the accounting timestamp from the Event-Timestamp Attribute Value Pair (AVP) of the interim accounting request.

6. The OFCS of claim 1 wherein:

the prior partial CDR includes at least one traffic data volume (TDV) container; and

the controller is configured to identify the CDR timestamp from the at least one TDV container in the prior partial CDR.

7. The OFCS of claim 1 wherein:

the prior partial CDR includes at least one service data container (SDC); and

the controller is configured to identify the CDR timestamp from the at least one SDC container in the prior partial CDR.

8. A method of generating partial Charging Data Records (CDRs) for a session after charging is handed over from a primary charging function of an Offline Charging System (OFCS) to the secondary charging function of the OFCS, the method comprising:

receiving, in a remediation system of the OFCS, an interim accounting request for the session from the secondary charging function after charging for the session was handed over from the primary charging function to the secondary charging function;

opening a next partial Charging Data Record (CDR) for the session after handover in the remediation system instead of in the secondary charging function based on the interim accounting request;

receiving a prior partial CDR for the session in the remediation system from the primary charging function;

parsing the prior partial CDR in the remediation system to identify a CDR timestamp;

recording a start time in the next partial CDR based on the CDR timestamp;

parsing the interim accounting request in the remediation system to identify an accounting timestamp for the session;

recording an end time in the next partial CDR based on the accounting timestamp;

closing the next partial CDR in the remediation system; and

transmitting the next partial CDR from the remediation system to a billing domain.

9. The method of claim 8 further comprising:

responsive to detecting handover of charging for the session from the primary charging function:

identifying, in the secondary charging function, the remediation system; and

routing the interim accounting request from the secondary charging function to the remediation system.

10. The method of claim 8 wherein:

the prior partial CDR includes multiple timestamps; and

the method further includes selecting one of the multiple timestamps that is associated with closure of the prior partial CDR as the CDR timestamp.

11. The method of claim 8 further comprising:

storing the prior partial CDR in memory in the primary charging function; and

responsive to detecting handover of charging for the session to the secondary charging function:

identifying, in the primary charging function, the remediation system; and

routing the prior partial CDR from the primary charging function to the remediation system.

12. The method of claim 8 wherein:

the interim accounting request comprises a Diameter request; and

the method further includes identifying the accounting timestamp from the Event-Timestamp Attribute Value Pair (AVP) of the interim accounting request.

13. The method of claim 8 wherein:

the prior partial CDR includes at least one traffic data volume (TDV) container; and

the method further includes identifying the CDR timestamp from the at least one TDV container in the prior partial CDR.

14. The method of claim 8 wherein:

the prior partial CDR includes at least one service data container (SDC); and

the method further includes identifying the CDR timestamp from the at least one SDC container in the prior partial CDR.