Structured Cabling Design Principles and Standards
- November 24, 2013
admin- Posted in:
Cable plant – cabling system in the enterprise including all the hardware. All the cable are following the same cabling standard. Standard is well know as the structured cabling. It is used in order to maximize performance while minimizing upkeep. Standard is independent from the type of the media that is being used in the network, it applies for copper based networks as well as for optical fiber. Figures 1 and 2 are showing structured cabling standard in the enterprise and in the building relatively.
Figure 1. TIA/EIA structured cabling in an enterprise.
Figure 2. TIA/EIA structured cabling in a building.
In order to better understand the Figures 1 and 2 – here is the legend with explanation:
-
Entrance facilities – service provider requires these facilities for connecting with different organisations’ LAN/WAN. It may include any type of wired or wireless devices, and media. Since it is providing maximum bandwidth available for the enterprise – usually it uses fiber-optic cable. Entrance facilities include demarc (demarcation point) – the point where internal network is connected to the service providers network.
-
MDF (main distribution frame/main cross connect) – first point in the network where LAN is connected with the service provider. MDF requires equipment capable of great throughput. MDF can be also known as the computer/equipment room.
-
Cross-connect facilities – the points of different circuits connection. It can be organised with a help of the punch-down block. From a punch-down block wires are connected to the patch panel.
- Punch-down block (shown in Figure 3) – a panel of data receptors used for connection in a convenient manner.
Figure 3. Punch-down block & patch panel.
-
Patch panel – wall mounted panel of data receptors, that allow insertion of patch cables.
-
IDF (intermediate distribution frame) – a junction point between MDF and further network concentrators.
-
Backbone wiring – wiring between entrance facilities, MDF, IDF and telecommunication closets.
-
Telecommunications closet – connection point for workstations in this area. It is connected to IDF or directly to MDF. Standard requires at least one telecommunications closet per floor with good cooling and ventilation.
-
Vertical cross-connect – type of backbone  wiring between the floors in the building. This type of connect require specific cables specified in Table 1.
Table 1. TIA/EIA specifications for backbone cabling.
Cable type | Cross-connects to telecommunications closet | MDF or IDF to telecommunications closet | Cross-connects to IDF or MDF |
UTP | 800 m (voice specification) | 500 m | 300 m |
Single-mode fiber | 3000 m | 500 m | 1500 m |
Multimode fiber | 2000 m | 500 m | 1500 m |
-
Horizontal wiring – wiring between workstation and telecommunications closet using STP/UTP/fiber-optic. Maximum distance for horizontal wiring is 100 m as shown in Figure 4.
Figure 4. Horizontal wiring.
-
Work area – are with workstations, horizontal wiring and other necessary devices that are required for connecting telecommunications closet with workstations NIC.