Function distribution in a packet switched network

A packet switched communication system employing ANR and/or multicast tree routing is improved by using a Copy ID field in the network header of the packet. The Copy ID field defines a control function and allows packet processing to be distributed among the several processors of each node. The selection of the processor (or processors) to receive the packet may be accomplished by making use of the routing field of the network header to qualify the control function specified in the Copy ID field. The control message is processed as defined for the control function by the processor receiving the packet. In multicast tree routing the control function is performed at all nodes in the multicast tree. In ANR routing, a prefacing "selective copy" bit is included in each label in the routing field of the network header; each node employed in the packet transmission path uses one label. The selective copy bit in each label triggers or not (according to its setting) the copy function in that node. The network control function specified in the Copy ID field may be performed in a given node when the copy function is triggered for that node.