A LAN comprises a plurality of nodes (6, 7) connected by LAN cables (14, 15) with conductors (9) dedicated to transmission of timing signals (2) alone or in addition to a power supply for equipment at the node. The conductors (9) may comprise a twisted pair. The conductors (9) may be connected between all ports or may be connected via a wiring box (11). The timing signal may be provided by a source (2) at a LAN connection device (1) or the wiring box (11) or at a node (17).
