A network element such as a router or switch provides application-level quality of service for application-layer messages processed in the network element, using application QoS logic which when executed by the one or more processors is operable to cause receiving an application-layer message; matching one or more attributes of the application-layer message to the message classification rules; determining a message classification of the application-layer message based on the matching; selecting one of the network-level QoS values using the mapping and based on the determined message classification; and marking a network-level header of the application-layer message using the selected QoS value. As a result, attributes of application messages at OSI Layer 5, 6, or 7 can be used to determine how to mark packets of the messages with QoS values at OSI Layer 2, 3 or 4, integrating application-level concepts of order and priority into network-layer QoS mechanisms.