The present application is at least directed to an apparatus on a network. The apparatus includes a non-transitory memory having instructions stored thereon for online charging of an event. The apparatus also includes a processor that is operably coupled to the non-transitory memory. The processor is configured to execute the instructions of receiving, from an M2M gateway, a rating request message for service layer online charging. The processor is also configured to execute the instructions of determining a rating scheme to charge for the event. The processor is further configured to execute the instructions of calculating an amount of service units based on the rating request message and determined rating scheme. The processor is even further configured to execute the instructions of sending, to the M2M gateway, a rating response based upon the calculated amount of service units.