Systems and methods for avoiding double accounting upon session failover

A method of performing offline charging in an Offline Charging System (OFCS) that includes a plurality of Charging Data Functions (CDFs), the method comprising:

• receiving, in a first CDF of the plurality, accounting requests for a session from a Charging Trigger Function (CTF);
• generating, at the first CDF, a first incomplete Charging Data Record (CDR) for the session based on the accounting requests;
• identifying, at the first CDF, request identifiers (ID) assigned to the accounting requests used to generate the first incomplete CDR;
• inserting, at the first CDF, the request IDs in a first extended field of the first incomplete CDR;
• determining, at the first CDF, whether at least one of the accounting requests used to generate the first incomplete CDR was indicated as a re-transmitted accounting request by the CTF;
• and
• inserting, at the first CDF, content information for the re-transmitted accounting request in a second extended field of the first incomplete CDR.

A non-transitory computer readable medium embodying programmed instructions executed by at least one processor to implement a plurality of Charging Data Functions (CDFs) of an Offline Charging System (OFCS), wherein the instructions direct the processor to:

• receive accounting requests for a session from a Charging Trigger Function (CTF);
• generate a first incomplete Charging Data Record (CDR) for the session based on the accounting requests;
• identify request identifiers (ID) assigned to the accounting requests used to generate the first incomplete CDR;
• insert the request IDs in a first extended field of the first incomplete CDR;
• determine whether at least one of the accounting requests used to generate the first incomplete CDR was indicated as a re-transmitted accounting request by the CTF;
• and
• insert content information for the re-transmitted accounting request in a second extended field of the first incomplete CDR.