1. A device-implemented method of complementing network discovery with physical discovery, said method comprising: using a device to perform: providing a universal physical discovery layer; providing a legacy network discovery layer that is implemented using a legacy network discovery protocol, wherein said legacy network discovery layer is separate from and communicates with said universal physical discovery layer; obtaining data representing a physical relationship type between physical entities in a network; using said data to establish by said device said physical relationship type at said universal physical discovery layer using said legacy network discovery layer, wherein said physical relationship type describes a relative physical proximity between said physical entities; and providing said physical relationship type for use at a physical entity of said physical entities wherein said device includes: a universal physical discovery layer component for providing a universal physical discovery layer; a universal physical discovery layer interface for obtaining, at least in part, data representing a physical relationship type between physical entities in a network; and said universal physical discovery layer component using said data to establish by said device said physical relationship type using a legacy network discovery layer interface to communicate with a legacy network discovery layer.