Non-linear data charging

A non-transitory computer-readable medium having instructions stored thereon that, when executed by a processor, cause the processor to charge a data session of a subscriber, the charging comprising:

• in response to a request to initiate the data session, providing a first quantity of granted service units of data for the data session associated with a first charging condition;
• during the data session, receiving a change in charging conditions for the subscriber;
• in response to the change, sending a re-authorization message to the subscriber;
• in response to the re-authorization message, receiving a first update message from the subscriber comprising a first used service units for the data session since the providing of the first quantity of granted service units of data;
• in response to the first update message and based on the change in charging conditions and the first used service units, providing a second quantity of granted service units of data for the data session associated with a second charging condition;
• and
• charging the data session of the subscriber according to a total used service units comprising the first used service units included with the first update message under the first charging condition and second used service units for the data session since the first update message under the second charging condition.

An Online Charging System (OCS) coupled to a user equipment (UE) and a Billing and Revenue Management System (BRM) through a communications network, the OCS comprising:

• a processor that generates and receives network messages over the network, the generating and receiving comprising:
• in response to a request to initiate the data session from the UE, providing to the UE a first quantity of granted service units of data for the data session associated with a first charging condition;
• during the data session, receiving a change in charging conditions for the UE from the BRM;
• in response to the change, sending a re-authorization message to the UE;
• in response to the re-authorization message, receiving a first update message from the UE comprising a first used service units for the data session since the providing of the first quantity of granted service units of data;
• in response to the first update message and based on the change in charging conditions and the first used service units, providing a second quantity of granted service units of data for the data session associated with a second charging condition to the UE;
• and
• charging the data session of the subscriber according to a total used service units comprising the first used service units included with the first update message under the first charging condition and second used service units for the data session since the first update message under the second charging condition.