Structured Cabling System (SCS)

Structured Cabling System (SCS)

• SCS is the complete cabling configuration and associated hardware installed at a site.
• It provides a comprehensive information transportation system infrastructure and is intended to serve a wide range of uses.
• The structured cabling system starts where the service provider (SP) terminates, known as the point of demarcation (demarc).
• Overall components and methods for structured cabling installation are relatively standard.
• Standards ensure consistency in design, installation, and maintenance, and aren't legally enforced but essential for system performance.

Key Components

• Entrance Facilities (EF) provide connection to external services.
• Equipment Rooms (ER) act as service provider rooms.
• Telecommunication Rooms (TR) function as the house MC/TTC.
• Telecommunications Enclosure (TE)
• Main Cross Connect (MC) often an MDF/MTTC/Bay Rack.
• Intermediate Cross Connect (IC) can act as a Satellite.
• Horizontal Cross Connect (HC) usually a TTC/Floor Distributor.
• Backbone Cabling and Pathways act as a riser.
• Horizontal Cabling and Pathways handle distribution.
• Telecommunications Outlets/Connectors (TO) are connection points for devices.
• Termination Hardware provides physical connection points for cables.
• Multi-User Telecommunications Assemblies (MUTOA) are consolidation points for multiple users.
• Transition Points (TP) where different types/categories of cable connect.
• Consolidation Points (CP)
• Horizontal Connection Points (HCP)
• Work Area (WA) is the end-user space.

Copper Cabling Standards

Twisted Pair Cabling

• Used for voice and data and consists of 22-26 AWG thermoplastic insulated conductors twisted together.
• Cables have a jacket or sheath for containment and protection.
• Cables have electrical performance characteristics.
• Balanced twisted pair cable and connecting hardware are recognized by TIA-568-C and ISO standards.
• Cables typically have an impedance of 100 ohms at 100 MHz.
• TIA recognizes 100Ω Unshielded Twisted Pair (UTP) and Shielded Twisted Pair (STP).

Balanced Twisted Pair

• Constructed of two conductors of equal length wound together to cancel electromagnetic interference (EMI) or crosstalk.

Twisted Pair Color Code

• Uses a color code for quick identification of pairs.
• Individual conductors: Tip and Ring.
• Five tip colors: white, red, black, yellow, violet(group)
• Five ring colors: blue, orange, green, brown, slate.(within group)
• Standard code IDs up to 25 pairs without duplicating color combinations.

Twisted Pair Cable Markings

• Cables designed for premise use must be marked for fire resistance rating and NEC article 800/CSA flame test (FT) ratings.

Plenum Cable (CMP)

• Used in ducts/plenums/building spaces and must have adequate fire resistance and low smoke characteristics.
• Plenum: compartment connected to air ducts and part of the air distribution system.
• Plenum rated cables/materials are required, or non-plenum cables must be in metal conduit.
• Applies to space above a suspended ceiling/under raised floor if used for environmental air handling.

Riser Cable (CMR)

• For vertical runs in shafts/spaces from floor to floor, with fire-resistant characteristics.

General Purpose Cable (CM)

• Used for general communications except riser/plenum spaces, and is resistant to fire spread.

Limited Use Cable (CMX)

• Used in dwellings/raceways, and is resistant to fire spread.

Undercarpet Cable (CMUC)

• CMUC undercarpet communications cables under carpet, resistant to the spread of fire.
• Not recommended nor used due to damage susceptibility and flexibility for moves.

Unshielded Twisted Pair Cable

• UTP Cable, classified as U/UTP, commonly used in premise or inside plant (ISP) environments.

Four Pair UTP Cable

• Used in horizontal distribution for work area cabling.
• Maximum distane limit 295 ft (90 m)

Multipair UTP Cable

• (more than four pairs) used for backbone distribution within a building.Multipair UTP cable is constructed in multiples of 25 pairs or more. Multipair UTP cable is specified in performance categories up to Category 5e.

Shielded Twisted Pair Cable

• Shielded Twisted Pair (STP) cable is most commonly used where performance requirements demand higher protection from outside noise sources
• Provides higher immunity on electromagnetic interference (EMI) and radio frequency interference (RFI).

Cable Shielding

• Shield can be made of foil or braided material

Connecting Hardware

• TIA standard requires insulation displacement connector IDC connectors to terminate twisted pair cables.
• IDC connections: insulation is not stripped when the conductor is inserted into the contact.

Twisted Pair Connectors

• Modular connectors for equipment lines or patch cords.
• Terminated on the connector rear.
• 8 position, 8 conductor connectors are used for four pair cable termination.
• Supports U/UTP, F/UTP, SF/UTP, S/FTP and U/FTP cables.

Pin/Pair Assignments

• The TIA-568-C standard, the T568A and T568B pin/pair assignments are the two recognized assignments for pin and pair.
• T568B pin/pair assignment used in most commercial installations. T568A is recommended for residential.

USOC Pin/Pair Assignment

• Universal Service Order Code (USOC) is another assignment used for telephony.
• USOC connectors are not recognized by the TIA-568 cabling standard.

66-Block Termination Hardware

• Used in voice applications. Updated to handle high speed data applications. Available in 25/50/100 pair configurations. Typically mounted on a wall or backboard with a standoff bracket.

110 Termination Hardware

• Used for voice and data applications. It can be wall- or rack-mounted and handle up to 300 pairs/block.

Patch Panels

• Patch panels are pre-loaded with 110 IDC connections.
• Empty patch panels are available for multiple media/custom applications.
• Designed for 19" standard racks and cabinets, with wall mounted patch panels as an option.

Work Area Components

• Work Area outlet includes standard faceplates, surface mount housings, and modular furniture faceplates
• Industrial outlets are rated IP67 class

Patch Cords

• Must be constructed of 100Ω balanced twisted pair and use T568A or T568B wiring.
• Patch cords must meet same transmission performance criteria. Constructed of stranded/solid conductors, shielded/unshielded.
• Commonly four-pair twisted-pair cables using "RJ-45" connectors with TIA/EIA-568 wiring.

Stranded conductor patch cords

• Preferred over solid because they're more flexible/durable with a longer flex life.
• Higher signal attenuation, allowed to exhibit 20-50% more attenuation than horizontal cabling.

Solid conductor patch cords

• Better attenuation than stranded but are not preferred.

Optical Fiber Cabling Systems

Optical Fibers

• Strands of ultra-pure glass transmitting light pulses instead of electrical signals.
• Constructed of strands of ultra-pure glass.
• Two main elements: core (ultra-pure glass, innermost part, light pulses guided) and cladding (surrounds the core, creates interface acting as a mirror, reflecting light pulses).
• Internal reflection: light pulses down the core of the fiber.
• Micrometer or micron (μm) is the size reference.
• Core's size ranges between 8 - 62.5 μm.
• All optical fiber strands have 125 µm diameter.
• Acrylate coating to handle.
• The application of the acrylate coating increases the original 125 µm diameter of the strand to 250 μm.
• Each optical fiber cable is protected w outter jacket to provide physical and environmental protection for the fiber strands inside the cable.

Optical Fiber Classifications

• Multimode or single mode.
• Four multimode classes, one single mode.

Optical Fiber Color Codes

• Premises cables and patch cords depend on fiber type. Outdoor has black jackets.

Optical Fiber Cable Markings

• Must be listed and marked for fire resistance rating.

Optical Fiber Cable Design

• Strand protection from aramid yarns running the length of the core.
• Physical might be added, such as fiberglass rod, corrugated steel tape, or steel wire armor.
• Environmental relies materials in the cable jacket. Water protection from gel/powder/tapes. OSP cables provide sheath protection from the extreme temperatures.

Premise Fiber Cable

• Designed for indoor usage listed to meet l building codes.

Tight Buffered Cable

• Coating of fiber provide ease of handling and connectorization.
• tight buffered cable is available with various jacket types to meet building code requirements.

Armored Cable

• designed for hars environments, armor of spiral wrapped steel, flame-retardant OFCR (Riser), or OFCP (Plenum) rated color jacket.

Outside Plant Optical Fiber Cable

• Designed for outdoor use, loose tube fiber, tight buffered construction may be needed depending on a specific application.

Ribbon Fiber

• has up to 24 strands bundled together in a single color-coded ribbon.

Optical Fiber Connectors

• Provide: Minimal power loss when connecting to other cables/equipments.
• Secure optical fiber retention, protection, connect/disconnect.
• Latching is achieved consisting of latching mechanism.

Backbone cabling systems

Functions

• Backbone cabling handles bulk telecommunications traffic, interconnecting EFs, TRs, ERs, and TEs
• cables either inter/intra building connects

Components

• cables, pathways, cross-connects, hardware, terminations, and patch cords/jumpers

Support Functions

• cable support hardware, firestopping, and grounding hardware 3.3.1 Network Topology

Bus Topology

• Linear appearance with devices connected to a single cable, common communication channel for all devices

Ring Topology

• Devices connected in a circle with information passing through each device, with an input and output port.

Star Topology

• Central switch, hub, or concentrator with devices connected like points on a star, used for backbone distribution
• MC to IC/HC (first level) and IC to HC (second level) are the two administrative levels.

Backbone Cross-Connect

topology should have a maximum of two levels of cross-connections.

• Connections between any two points should not pass through more than three cross-connections.

Main Cross-Connect (MC)

• Located in the ER, connects entrance cables, backbone cables, and equipment cables

ntermediate Cross-Connect (IC)

• Located between the MC and HC in interbuilding backbone cabling

Horizontal Cross-Connect (HC)

• Connects horizontal cabling to other cabling and equipment.

Horizontal Cabling System

• Backbone distance limitations depend on media type and application.

Horizontal Cabling

• Cabling runs in ceilings or under floors that connect TRs/TEs to work area outlets.
• Contains 4-pair 100Ω UTP/STP, optical fibers, outlets/connectors, terminations, patch panels, and/or MUTOAs, CPs, and TPs.

Permanent Link

• Includes all horizontal cabling components, but not equipment cords. It has a 90m (295ft) max length.

Channel Link

• Has all components of horizontal cabling system, that include cables and patch cords. Patch cords added up to 10m (33ft). Max overall length is is 100m (328ft).

transition points

• where flat undercarpet cable (CMUC) connects to round cable
• undercarpet cabling is not a best practice

multi-User Telecommunications Outlet Assembly(MUTOA)

• is infrequently reconfigured with open office spaces
• Maintains cabling integrity during reconfigurations, Multiple work areas served by one or more MUTOAs

Telecommunications Pathways Spaces

Entrance facilities

Provide a means to connect the outside service facilities to the premise cabling that serves as the point of demarcation for the Service Provider

Aerial Entrance

• Service provider attaches to building/pole pedestal and installs entrance cable through an entrance conduit, w Attachments on the building side nearest the pole: clearance is 5.5m over streets