A central point of interconnection for devices on a local area network (LAN) or LAN segment. Hubs act as passive LAN concentrators and repeaters, with a single internal collapsed backbone bus typically running at a signaling rate of 10/100 Mbps. LAN-attached devices such as workstations, peripherals, and servers typically connect to a hub via either unshielded twisted pair (UTP) or shielded twisted pair (STP). Hubs operate at Layer 1, the Physical Layer of the OSI Reference Model. Filtering hubs also operate at a portion of Layer 2, the Data Link Layer. See also 10Base-T, 100Base-T, concentrator, Data Link Layer, LAN, OSI Reference Model, Physical Layer, repeater, STP, and UTP.