A source node for configuring and transmitting packets is provided that comprises (a) a reservation agent 204 configured to assign to a first packet a preemption level causing at least some routers in the distributed processing network to process the first packet differently than other packets not having the preemption level, (b) a preemption map 208 comprising a plurality of preemption levels (each preemption level being associated with predetermined level identification criteria), and/or (c) sender-specific information 212 associated with a sender. The reservation agent 204 can configure and transmit packets containing a preemption level and/or sender-specific information.