Apparatuses, methods, and systems are disclosed for monitoring a QoS parameter. One UPF apparatus includes a network interface that receives a request to monitor a QoS parameter for a data connection of a remote unit and a processor that modifies a downlink packet to include an indication for a QoS monitoring report. Via the network interface, the processor receives a QoS monitoring result from the access network node in response to the modified downlink packet and determines a value of the QoS parameter based on delivery information of the downlink packet.