Lines patched as data ports into a network switch require simple straight-through patch cables at each end to connect a computer. Voice patches to PBXs in most countries require an adapter at the remote end to translate the configuration on 8P8C modular connectors into the local standard telephone wall socket. No adapter is needed in the U.S. as the 6P2C and 6P4C plugs most commonly used with RJ11 and RJ14 telephone connections are physically and electrically compatible with the larger 8P8C socket. RJ25 and RJ61 connections are physically but not electrically compatible, and cannot be used. In the UK, an adapter must be present at the remote end as the 6-pin BT socket is physically incompatible with 8P8C.
It is common to color code patch panel cables to identify the type of connection, though structured cabling standards do not require it except in the demarcation wall field.
Cabling standards demand that all eight conductors in Cat5/5e/6 cable are connected, resisting the temptation to ‘double-up’ or use one cable for both voice and data. IP phone systems, however, can run the telephone and the computer on the same wires.
Structured cabling falls into six subsystems:
• Entrance Facilities is the point where the telephone company network ends and connects with the on-premises wiring at the customer premises.
• Equipment Rooms house equipment and wiring consolidation points that serve the users inside the building or campus.
• Backbone Cabling connects between the equipment/telecommunications rooms, so named because the rooms are typically on different floors.
• Horizontal Cabling wiring can be IW (inside wiring) or Plenum Cabling and connects telecommunications rooms to individual outlets or work areas on the floor, usually through the wire ways, conduits or ceiling spaces of each floor.
• Telecommunications Rooms or Telecommunications Enclosure connects between the backbone cabling and horizontal cabling.
• Work-Area Components connect end-user equipment to outlets of the horizontal cabling system.
