A device may receive performance information for a traffic flow assigned to a quality of service (QoS) class. The device may determine an overall packet delay, associated with the traffic flow, based on the performance information. The device may determine a radio access network (RAN) delay, associated with the traffic flow, based on the performance information. The device may determine a target packet delay associated with the QoS class. The device may identify, based on the target packet delay, the RAN delay, and the overall packet delay, a QoS sub-class to which the traffic flow is to be assigned. The QoS sub-class may be associated with the QoS class. The device may cause packets, associated with the traffic flow, to be marked for treatment in accordance with the QoS sub-class.