A method, system, and computer program product for determining a congestion value in a networking component in a data network are provided in the illustrative embodiments. A first packet is set to use a first priority level and a second packet is set to use a second priority level. The second priority level is lower than the first priority level. The second packet is transmitted after the first packet to the networking component, causing the networking component to transmit the first and the second packets after they are received at the networking component. A function is applied to an arrival delay to compute the congestion value of the networking component, wherein the arrival delay comprises a length of an elapsed period between receiving a transmission of the first packet from the networking component and receiving a transmission of the second packet from the networking component.