Abstract: A data transmission network comprises a plurality of packet switches distributed throughout the network for transmitting data between a data source and destination. The destination of the incoming data is identified and a path created through the network to said destination based on the destination. The incoming data are assembled into packets. In the packets are included a plurality of routing codes defining the path through successive switches in the network. The packet switches for interpret the routing codes in the received packets and route the packets to the next switch until the destination is reached.