Patent ID: 7801815

Claim:
A method for determining a maximal service event duration, the method comprising: receiving a reverse rating message for a telecommunications service use transaction and a time rate applicable for a customer at a starting event time; determining, with a processor, a time duration result based on an account balance and the time rate; establishing, with the processor, a resource expenditure threshold; until a termination condition is satisfied, repeatedly performing with the processor: segmenting the time duration result into a partial duration result and a remainder; updating a running sum that with the partial duration result; updating the account balance and time rate based on the partial duration result to obtain an updated account balance and an updated time rate; monitoring a resource expenditure as the running sum is updated; re-determining the time duration result based on the remainder, updated account balance and updated time rate; and determining whether the termination condition is satisfied by: determining whether the resource expenditure exceeds the resource expenditure threshold; and determining whether there are no more partial duration results to segment from the time duration result; and when the resource expenditure exceeds the resource expenditure threshold, communicating the running sum as an approximation to the maximal duration of the service use transaction; and when the resource expenditure does not exceed the resource expenditure threshold and there are no more partial duration results to determine, communicating the running sum as the maximal duration of the service use transaction.