1. In a packet switched data communications network, the network including a plurality of end systems and switches connected by links, each switch having at least one network port connected to another switch and some switches having access ports connected to end systems, and each end system having a unique physical layer address, each switch including a connection database of valid connections between different ports on the switch and a switching mechanism for establishing temporary connections between the different ports on the switch, the improvement comprising: a connection server coupled to each switch, means coupled to each switch and the connection server for registering each switch with the connection server, and means, prior to transmission of a data packet comprising a connectionless datagram from a first end system having a first physical layer address to a second end system having a second physical layer address, for determining a path from the first end system to the second end system through one or more of the switches and for configuring the connection database of each respective switch on the path with a connection identifier including the first physical layer address and the second physical layer address of the first and second end systems, respectively, the determining and configuring means being coupled to each switch and the connection server, and the data packet remaining as a connectionless datagram as the data packet is transmitted through the respective switches along the path.