Re: Lies, damned lies, and statistics that don't lie.
On ethernet, DECnet phase 4 encoded the area number (1-63) and the node within the area (1-1023) into the last 16 bits of the MAC address. This provided a means for DECnet nodes on the same ethernet to find one another without using a router. DECnet was designed to work over serial links as well as ethernet but required either a routing license (expensive) or a DECnet router (even more expensive) for a node that had more than one link. The elegant kludge of the MAC address allowed nodes with only one link (an ethernet connection) to communicate with other nodes on the same ethernet without needing a router.