| :: What is structured cabling? | | | | a hub or switch is connected to each station |
| Modern computer LAN (local area network) wiring | | | | cable, which electrically terminates the cable run. |
| has the concept of structured cabling. | | | | The hub or switch then passes the computer |
| With today's high speed networks, people realize | | | | signal on to other work stations or servers, or |
| that the networking system must be broken up | | | | even to other telecom rooms for ultimate |
| into shorter chunks that allow workstation wiring | | | | connectivity with the entire network. |
| to be concentrated, with each cable length short | | | | :: Vertical Cabling (Backbone Cabling) |
| enough to support the high data rate. | | | | Telecom rooms on each floor are then connected |
| Based on aforementioned reasons, structured | | | | together by backbone cabling (also called vertical |
| wiring standard has been developed to help define | | | | cabling for floor to floor connections). These |
| a computer wiring system that stays within the | | | | backbone cablings typically are done from floor to |
| maximum wiring distance for various LAN | | | | floor to floor. |
| topologies. For example, the horizontal cable wiring | | | | Usually telecom rooms should be located directly |
| length is 100 meters for 100BaseT networks. | | | | above one another in order to minimize the cable |
| :: What do we do to observe the 100 meters | | | | runs length, but this also varies from building to |
| wiring standard? | | | | building. |
| In order to achieve the wiring concentration | | | | With the emerge of Gigabit Ethernet and 10 |
| standard, telecommunication rooms (wiring | | | | Gigabit Ethernet, fiber optic cable is the most |
| centers) are placed at planned locations in a | | | | appropriate choice for backbone cabling since they |
| building. These telecom rooms are then | | | | provide much higher bandwidth than traditional |
| interconnected to provide the total network | | | | Cat5, Cat6 or even Cat7 twisted pair copper |
| connectivity for the building. | | | | cables. Another advantage of fiber is that fibers |
| This can be explained in a three stories building. At | | | | can run much longer distance than copper cable, |
| one same corner of each floor, a telecom rooms | | | | which makes them especially attractive for |
| is constructed; these telecom rooms are then | | | | backbone cabling. |
| connected by backbone wiring (cables run | | | | :: The difference between backbone cabling and |
| vertically through the floors and link all telecom | | | | horizontal cabling |
| rooms together). | | | | Since backbone cabling typically passes through |
| On each floor, a telecom room concentrates all | | | | from floor to floor, the cables used for backbone |
| workstation cables for that floor. Each | | | | cabling have very different requirement than the |
| workstation has a wall mounted jack. The | | | | horizontal cablings. |
| network cable is terminated at that jack and runs | | | | 1. Fire ratings. Backbone cables must have |
| directly to the telecom room. The cable may run | | | | standard imposed fire rating specifications. |
| in wire trays or conduit, or be draped over | | | | Typically this is OFNR (Optical Fiber |
| supports such as a drop ceiling. For larger floors, | | | | Non-Conductive Riser) rated. If the backbone |
| more than one telecom room may be needed. | | | | cable passes through plenum area (spaces in the |
| :: Horizontal Cabling | | | | building used for air return in air conditioning), the |
| The horizontal wires, which run from workstations | | | | cable must be OFNP (Optical Fiber Non-conductive |
| on the same floor to the telecom room, are then | | | | Plenum) rated. |
| terminated on punchdown termination, or directly | | | | 2. Physical securing. Physical securing for vertical |
| onto a patch panel. The punchdown terminations | | | | riser cables is also different than horizontal cables. |
| or patch panels could be rack mounted (19" or | | | | So is the cable strength, since vertical riser cables |
| 23" racks), cabinet mounted or wall mounted. | | | | need to have enough strength to support its own |
| In the telecom room, network equipment such as | | | | weight. |