Patent ID: 8315925

Claim:
A computer network system for generating Charging Data Records (CDRs), the computer network system comprising: a primary Charge Collection Function (CCF) system comprising a first processor configured to receive and correlate Account Request messages (ACRs) relating to a chargeable session and to generate CDRs, wherein each CDR providing information about the chargeable session in the network system is based on a set of ACRs relating to the same chargeable session and each set of ACRs includes at least an ACR Start message indicating the start of the chargeable session and an ACR Stop message indicating the end of the chargeable session; a secondary CCF system comprising a second processor configured to receive and correlate ACRs and to generate CDRs, each CDR based on a received set of ACRs relating to the same chargeable session; and a Charge Trigger Function (CTF) system comprising a third processor configured to: generate sets of ACRs and to normally deliver each set to the primary CCF system; and in response to a shutdown notice indicating that the primary CCF system is expected to shutdown, received after the CTF system delivers an ACR Start message to the primary CCF system but before the CTF system delivers an ACR Stop message relating to the same chargeable session to the primary CCF system: deliver an ACR Stop message relating to the same chargeable session to the primary CCF system before the primary CCF system shuts down; and deliver an additional ACR Start message and an ACR Stop message relating to the same chargeable session to the secondary CCF system.