Network devices facilitate flow management through packet marking. The network devices may be switches, routers, bridges, hubs, or any other network device. The packet marking may include analyzing received packets to determine when the received packets meet a marking criterion, and then applying a configurable marking function to mark the packets in a particular way. The marking capability may facilitate deadline aware end-to-end flow management, as one specific example. More generally, the marking capability may facilitate traffic management actions such as visibility actions and flow management actions.