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Some specifications related to work area cabling include:

• Equipment cords are assumed to have the same performance category as the horizontal cable to which they connect.
• When used, adapters are assumed to be compatible with the transmission capabilities of the equipment to which they connect.

Note:

For establishing maximum horizontal link distances, a combined maximum length of 10m (33 ft.) is allowed for patch cables (or jumpers) and for equipment cables in the work area and the telecommunications room.

Horizontal Distances of Copper Links (Open Office)

The table entries assume that there is a total of 5m (16 ft.) of patch and equipment cables in the telecommunications room. 

Telecommunications Room

Telecommunications Rooms (TR) are generally considered to be floor serving facilities for horizontal cable distribution. They may also be used for intermediate and main cross-connects.

Some specifications to the telecommunications room:

• Cable stress from tight bends, cable ties, staples, and tension should be avoided by well-designed cable management.
• Only standards-compliant connecting hardware shall be used.
• Application-specific electrical components shall not be installed as part of the horizontal cabling.
• Horizontal cable terminations shall not be used to administer cabling system changes. 
• Instead, jumpers patch cords, or equipment cords are required for re-configuring cabling connections.

Some points for the horizontal cabling subsystem include:

• Recognized Horizontal Cables:

  4-pair 100 Ω unshielded twisted-pair  

  2-fiber (duplex) 62.5/125µm or 50/125µm multimode optical fiber.

• Multi-unit cables are allowed, provided that they satisfy the hybrid/bundled cable requirements. 
• Grounding shall conform to applicable building codes and the requirements of ANSI-J-STD-607-A.
• A minimum of two telecommunications outlets are required for each individual work area. 
• One transition point (TP) or Consolidation Point (CP) is allowed. The term "transition point" was removed from the second edition of ISO/IEC 11801:2002. Under carpet cabling is no longer recognized by that standard.
• Additional outlets may be provided.
• Bridged taps and splices are not allowed for copper-based horizontal cabling. (Splices are allowed for fiber.)
• Application specific components shall not be installed as part of the horizontal cabling. When needed, they must be placed external to the telecommunications outlet or horizontal cross-connect (eg. splitters, baluns).
• The proximity of horizontal cabling to sources of electromagnetic interference (EMI) shall be taken into account.

Backbone Cabling Structure

The backbone cabling system provides interconnections between telecommunications rooms, equipment rooms, main terminal space, and entrance facilities. It includes backbone cables, intermediate and main cross-connects, mechanical terminations, and patch cords or jumpers used for backbone-to-backbone cross-connections. The backbone also extends between buildings in a campus environment.

Some points specified for the backbone cabling subsystem include:

• Equipment connections to backbone cabling should be made with cable lengths of 30m (98 ft.) or less.
• The backbone cabling shall be configured in a star topology. Each horizontal cross-connect is connected directly to a main cross-connect or to an intermediate cross-connect, then to a main cross-connect.
• The backbone is limited to no more than two hierarchical levels of cross-connects (main and intermediate). No more than one cross-connect may exist between a main and a horizontal cross-connect and no more than three cross-connects may exist between any two horizontal cross-connects.
• A total maximum backbone distance of 90m (295 ft.) is specified for high bandwidth capability over copper. This distance is for uninterrupted backbone runs. .
• The distance between the terminations in the entrance facility and the main cross-connect shall be documented and should be made available to the service provider.
• Recognized media may be used individually or in combination, as required by the installation. Quantity of pairs and fibers needed in individual backbone runs depends on the area served. Recognized backbone cables are:

100 Ω UTP

Twisted-Pair

100 ΩF/UTP

Shielded Twisted-Pair

100 ΩS/FTP

50/125μm or 62.5/125μm

Multimode Optical Fiber

Singlemode Optical Fiber

• Multi-pair cable is allowed, provided that it satisfies the power sum crosstalk requirements.
• The proximity of backbone cabling to sources of electromagnetic interference (EMI) shall be taken into account.
• Cross-connects for different cable types shall be located in the same facilities.
• Bridged taps and splitters are not allowed.

Transmission Performance Specifications For Field Testing of Balanced Cabling Systems

This provides users with the opportunity to use comprehensive test methods to validate the transmission performance characteristics of installed category 7, 6, 5e and lower grade twisted-pair cabling systems. 

Horizontal Channel (Copper)

Transmission Performance Comparison @ 100 MHz

*Not specified by TIA

Link Test Configuration

Transmission Performance Comparison @ 100 MHz

Some points for testing for twisted-pair cabling systems:

• Twisted-Pair cabling systems are comprised of cables and connecting hardware. 
• Required test parameters include wire-map, length, insertion loss, and pair-to-pair NEXT loss, powersum NEXT loss, ELFEXT, powersum. ELFEXT, return loss, propagation delay, and delay skew.
• Two levels of pass or fail are indicated, depending on measured margin compared to minimum specifications. Testing of NEXT loss is required in both directions.
• Requirements are intended for performance validation.