The present invention provides a network node and corresponding methods for implementing a Quality of Service (QoS) mechanism in an Internet Protocol (IP) network. The network node comprises a swapping table comprising swapping records. Each swapping record lists an incoming network path and an associated QoS Class, an outgoing network path associated with the incoming network path. Each swapping records also lists a second QoS Class and an output port of the network node associated with the outgoing network path. The network node also comprises a communication module capable of receiving packet flows on one of the incoming network paths and directing the packets from the packet flows into packet queues each having an associated QoS classification corresponding to the QoS Class of the outgoing network path associated with the incoming network path on which the packets have been received, and as listed in the swapping table.