Chapter 5 - Horizontal Distribution System

Question 1

The maximum standards-recommended length of an Ethernet passive optical network (EPON) is:

a. 10 km (6.2 mi)
b. 20.1 km (12.5 mi)
c. 40 km (25 mi)
d. 60 km (37 mi)

Answer 1

a. 10 km (6.2 mi)

p 5-60 Table 5.5

Maximum channel attenuation = 20 dB

Question 2

The maximum standards-recommended length of a 10G-EPON is:

a. 10 km (6.2 mi)
b. 20 km (12.5 mi)
c. 40 km (25 mi)
d. 60 km (37 mi)

Answer 2

b. 20 km (12.5 mi)

p 5-60 Table 5.5

Maximum channel attenuation = 29 dB

Question 3

The maximum standards-recommended length of a GPON (B+ Optics) is:

a. 10 km (6.2 mi)
b. 20 km (12.5 mi)
c. 40 km (25 mi)
d. 60 km (37 mi)

Answer 3

b. 20 km (12.5 mi)

p 5-60 Table 5.5

Maximum channel attenuation = 28 dB

Question 4

The maximum standards-recommended length of a 10GPON is:

a. 10 km (6.2 mi)
b. 20.1 km (12.5 mi)
c. 40 km (25 mi)
d. 60 km (37 mi)

Answer 4

c. 40 km (25 mi)

p 5-60 Table 5.5

Maximum channel attenuation = 31 dB

Question 5

The maximum standards-recommended length of a GPON (C+ Optics) is:

a. 10 km (6.2 mi)
b. 20.1 km (12.5 mi)
c. 40 km (25 mi)
d. 60 km (37 mi)

Answer 5

d. 60 km (37 mi)

p 5-60 Table 5.5

Maximum channel attenuation = 32 dB

Question 6

The ceiling zone method of pathway distribution for horizontal cabling divides the usable floor area into zones, with each zone measuring a minimum of:

a. 9.3 m² (100 ft²)
b. 70 m² (750 ft²)
c. 46 m² (500 ft²)
d. 23 m² (250 ft²)

Answer 6

d. 23 m² (250 ft²)

p 5-95

In the ceiling zones method of ceiling distribution, the usable floor area should be divided into zones of ≈23.2 m² (250 ft²) to ≈92.9 m² (1000 ft²) each.

Question 7

10 Gb/s passive optical networks (10GPONs) require connectors that are capable of reducing back reflection in the _____ and above wavelength range.

a. 850 nm
b. 1310 nm
c. 1300 nm
d. 1500 nm

Answer 7

d. 1500 nm

p 5-58

It is recommended that APC connectors be utilized. The requirements for both current RF injection and current 10GPON and 10G-EPON solutions implies that the end-to-end optical fiber cabling link shall use APC connections to reduce back reflection in the 1500 nm and above wavelength range.

Question 8

The OLT is commonly referred to as the aggregation point of a PON architecture. The OLT provides multiple high-bandwidth ___ and ___ Gb/s interfaces via pluggable optics.

a. 1, 10
b. 10, 40
c. 40, 100

Answer 8

a. 1, 10

p 5-58

The OLT is commonly referred to as the aggregation point of a PON architecture. The OLT provides multiple high-bandwidth 1 Gb/s and 10 Gb/s interfaces via pluggable optics to the:

• Customer WAN or core network.
• PON switch fabric.
• PON interface cards.

Question 9

Elbows, reducers, crossovers, and tees are examples of fittings used to change the _____ of a cable tray.

a. Size, shape, or direction
b. Direction or shape
c. Size or direction
d. Shape
e. Size

Answer 9

c. Size or direction

p 5-106

The fittings used for changing the direction or size of a cable tray include:

• Elbows.
• Reducers.
• Crossovers.
• Tees.

Question 10

The recommended uniform load capacity for an access floor system to be installed in a medium-duty equipment room environment is:

a. 12 kPa (250 lbf/ft 2)
b. 9.6 kPa (200 lbf/ft 2)
c. 4.8 kPa (100 lbf/ft 2)
d. 2.4 kPa (50 lbf/ft 2)

Answer 10

c. 4.8 kPa (100 lbf/ft 2)

p 5-90

Equipment room (medium duty)

• Uniform Load Capacity ≈4.8 kPa (100 lbf/ft2)
• Concentrated Load Capacity ≈8.8 kN (2000 lbf)

General office (medium duty)

• Uniform Load Capacity ≈2.4 kPa (50 lbf/ft2)

Question 11

Floor loading of equipment cabinets varies from:

a. 50 to 100 lbf/ft2
b. 50 to 250 lbf/ft2
c. 00 to 200 lbf/ft2
d. 100 to 300 lbf/ft2

Answer 11

a. 50 to 100 lbf/ft2

p 5-90

See Table 5.15

Question 12

The recommended maximum cable length from the centralized crossconnect to the work area for the pull-through method of centralized optical fiber cabling is:

a. 500 m (1640 ft)
b. 300 m (984 ft)
c. 100 m (328 ft)
d. 90 m (295 ft)

Answer 12

d. 90 m (295 ft)

p5-45 Figure 5.21

Question 13

A(n) _____ in the horizontal cabling allows open office spaces to be reconfigured without disturbing cabling runs.

a. Cross-connection
b. Interconnection

Answer 13

b. Interconnection

p 5-20

Question 14

The standards for Ethernet and 10 Gb/s Ethernet passive optical networks (EPON and 10G-EPON) are issued by:

a. ISO
b. TIA
c. IEEE
d. ITU

Answer 14

c. IEEE

p 5-57

GPON = ITU G.984

EPON = IEEE 802.3ah

10GPON = ITU G.987

10G-EPON = IEEE 802.3av

Question 15

When selecting balanced twisted-pair cabling for PoE power delivery, lighting is considered to have _____ requirements.

a. High power / high data
b. High power / low data
c. Low power / high data
d. Low power / low data

Answer 15

b. High power / low data

p 5-40

Lighting is low data/high power; therefore, 23 AWG min/22 AWG conductors may be recommended.

Question 16

MUTOAs can be used to service work area devices in furniture clusters and wireless access points (WAPs).

a. True
b. False

Answer 16

b. False

p5-29

When using MUTOAs in areas with WAPs, give special attention to the installation of the cabling to access points directly from the TR/TE, not from the MUTOA located in the area. MUTOAs are only intended to service devices in furniture clusters.

Question 17

Equipment cords and coverage area cables used for data and power transmission should have conductors with a minimum size of 0.205 mm2 (24 AWG).

a. True
b. False

Answer 17

a. True

p 5-38

Question 18

When testing the optical fiber cabling installed for a passive optical network (PON), the tester head stays stationary at the optical _____ terminal while the remote is moved across all splitter outputs

a. Unit
b. Source
c. Network
d. Line

Answer 18

d. Line

p 5-64

This should be an end-to-end test, placing one end of the tester at the primary PON singlemode optical fiber jumper cable that would connect to the OLT, through the splitter, and then allow for a reading to be taken on every drop cable at each ONT.

All optical fiber cabling within a PON installation should be tested for bidirectional loss at 1310 nm and 1550 nm wavelengths.

Question 19

In a fiber-to-the-outlet (FTTO) installation, active LAN equipment in located in the TR.

a. True
b. False

Answer 19

b. False

p5-50

There is no active LAN equipment in the TR; the horizontal optical fiber cable is connected to the multi-strand backbone optical fiber cable by splicing as per the centralized cabling concept.

Question 20

When selecting balanced twisted-pair cabling for PoE power delivery, shielded cables often exhibit _____ heat build-up than comparable unshielded cables.

a. More
b. Less

Answer 20

b. Less

p5-40

When selecting balanced twisted pair cabling, shielded cables often exhibit less heat build-up than comparable unshielded cables

Question 21

Perimeter raceways should be used primarily for large floor areas where a majority of telecommunications service will be along the walls.

a. True
b. False

Answer 21

b. False

p5-111

Perimeter raceways should be used primarily for small floor areas where the majority of telecommunications service will be along the walls as shown in Figure 5.35.

Question 22

_____ are not allowed in any balanced twisted-pair cabling system due to the significant risk of decreased performance.

a. Undercarpet telecommunications cables
b. Bridged taps

Answer 22

b. Bridged taps

p 5-16

Because of the significant risk of decreased performance, bridge taps are not allowed in any balanced twisted-pair cabling system (ISP and OSP).

Question 23

The Power over HDBaseT (PoH) standard delivers a maximum of _____ over four balanced twisted-pairs.

a. 100 W

b 95 W

c. 60 W
d. 30 W

Answer 23

b 95 W

p5-37

HDBaseT Alliance created a Power over HDBaseT (PoH) standard that delivers a maximum of 95 W over four pairs. HDBaseT 1.0 and HDBaseT 2.0 have the same power specifications

Question 24

When designing a MUTOA environment, 24 AWG work area equipment cords must not exceed _____ in length.

a. 30 m (98 ft)
b. 27 m (89 ft)
c. 22 m (72 ft)
d. 18 m (59 ft)

Answer 24

c. 22 m (72 ft)

p 5-28

Do not use 24 AWG work area equipment cords with lengths that exceed ≈22 m (72 ft).

Question 25

Application-specific devices are considered to be part of the horizontal cabling system

a. True
b. False

Answer 25

b. False

p 5-15

Application-specific devices shall not be used as part of the horizontal cabling system, and they shall be kept external to the telecommunications outlet/connector and HC (FD).

Question 26

When telecommunications cabling pathways run parallel to power cabling pathways, it is recommended to provide a minimum of _____ separation.

a. 152 mm (6 in)
b. 102 mm (4 in)
c. 25.4 mm (1 in)
d. 51 mm (2 in)

Answer 26

d. 51 mm (2 in)

p 5-115

When telecommunications cabling pathways run parallel to electrical pathways, the recommendation is a minimum of ≈51 mm (2 in) separation.

Question 27

For new installations, consider specifying cabling with 0.326 mm2 (22 AWG) conductors if the specific building system is expected to require power exceeding _____ during the life cycle of the building.

a. 90 W
b. 80 W
c. 70 W
d. 60 W

Answer 27

d. 60 W

p 5-38

For new installations, consider specifying cabling with 0.326 mm2 (22 AWG) conductors if:

• The specific building system (e.g., audio systems, video displays) is expected to require power exceeding 60 W during the life cycle of the building

Question 28

When planning the location of telecommunications outlets, a minimum of _____ telecommunications outlet box(es) must be placed in each work area.

a. One
b. Two
c. Three

Answer 28

a. One

p 5-22

Each work area shall have a minimum of one telecommunications outlet with a minimum of two recognized connectors per outlet.

Question 29

The Americans with Disabilities Act (ADA) requires the installation of one interior text capable telephone (TTY) on each floor of a site with _____ or more public telephones.

a. One
b. Two
c. Three
d. Four

Answer 29

d. Four

p 5-119

One interior TTY shall be provided on each floor of a site with four or more public telephones as long as one of the four telephones is located inside the facility and at each bank of four or more public telephones.

Question 30

When selecting balanced twisted-pair cabling for PoE power delivery in BAS applications, conductor size is not considered critical to the PoE implementation.

a. True
b. False

Answer 30

a. True

p 5-40

BAS/BMS and facility controls are low power/low data, so conductor size is NOT critical to the PoE implementations. Cable jacket temperature rating of 75 °C (167 °F) and shielding should be given consideration, based on environment

Question 31

When power is applied to twisted-pair cabling, the level of temperature rise will increase when cables are bundled. For all cables, the recommended maximum bundle size is:

a. 30
b. 24
c. 12
d. 6

Answer 31

b. 24

p 5-41

For all cables, recommended maximum bundle size is 24 cables.

Question 32

Which one of the following types of transmission media are not allowed in the horizontal cabling system?

a. OS2 singlemode optical fiber
b. OS1 singlemode optical fiber
c. OS1a singlemode optical fiber

Answer 32

b. OS1 singlemode optical fiber

p 5-17

OS1a and OS2 optical fiber singlemode minimum 2-strand cables and corresponding connecting hardware

Question 33

If non-continuous supports are used as ceiling-based pathways for horizontal cabling, they must allow for cable sag while keeping cables a minimum of _____ above the ceiling grid.

a. 152 mm (6 in)
b. 102 mm (4 in)
c. 77 mm (3 in)
d. 51 mm (2 in)

Answer 33

c. 77 mm (3 in)

p 5-98

Specify that non-continuous supports are installed at intervals not exceeding

≈1.52 m (5 ft) that will minimize cable sag while keeping cables a minimum of

≈77 mm (3 in) above ceiling grid.

Question 34

The addition of either a CP or MUTOA creates an additional connection point in a horizontal cabling run.

a. True
b. False

Answer 34

b. False

p5-29

The functional difference between the CP and the MUTOA in the open office environment is that the CP introduces an additional connection for each horizontal cabling run.

Question 35

A fiber-to-the-outlet (FTTO) installation uses core and distribution switches that are located in the:

a. Equipment room
b. Telecommunications room
c. Work areas

Answer 35

a. Equipment room

p 5-54

The FTTO design uses core and distribution switches in the equipment room and the micro switches in work areas. There are no other active network equipment in the floor serving TR. The type and configuration of the core and distribution switches will depend upon the number of micro switches and the redundancy required.

Question 36

When designing a centralized optical fiber cabling installation using the pull-through method, it is recommended to limit cabling length to the maximum allowed by the intended application or _____, whichever, is smaller.

a. 550 m (1804 ft)
b. 305 m (1000 ft)
c. 100 m (328 ft)

Answer 36

b. 305 m (1000 ft)

p 5-46

It is recommended that optical fiber cabling lengths do not exceed the maximum length limit for the application or ≈305 m (1000 ft), whichever is smaller.

Question 37

The recommended amount of cable slack in the telecommunications room for an optical fiber horizontal cabling system is:

a. 10 m (33 ft)
b. 4.6 m (15 ft)
c. 3 m (10 ft)
d. 2.1 m (7 ft)

Answer 37

c. 3 m (10 ft)

p 5-19

Optical fiber cabling—Sufficient to reach the farthest corner of the TR via the pathways plus the distance from floor to ceiling and an additional ≈3 m (10 ft) of slack for storage inside hardware without exceeding the ≈90 m (295 ft) limitation.

Question 38

There are _____ variants of redundancy possible in a fiber-to-the-outlet (FTTO) design.

a. Four
b. Three
c. Two

Answer 38

a. Four

p 5-54

There are four variants of redundancy possible in the FTTO design

Question 39

_____ is a method where two connecting hardware units (e.g., balanced twisted-pair, optical fiber) are linked by patch cords or jumpers and used to connect active equipment to the horizontal cabling system.

a. Interconnection
b. Cross-connection

Answer 39

b. Cross-connection

p 5-10

Cross-connection is a method where two connecting hardware units (e.g., balanced twisted-pair, optical fiber) are linked by patch cords or cross-connect jumpers and used to connect active equipment to the horizontal cabling system.

Question 40

A work area telecommunications outlet box should be located within _____ of an electrical outlet.

a. 1 m (3.3 ft)
b. 0.91 m (3 ft)
c. 300 mm (12 in)
d. 0.6 m (2 ft)

Answer 40

a. 1 m (3.3 ft)

p 5-23

The work area telecommunications outlet box should be located near an electrical outlet (e.g., within ≈1 m [3.3 ft]) and installed at the same height

Question 41

Application-specific devices are considered to be part of the horizontal cabling system.

a. True
b. False

Answer 41

b. False

p 5-15

Application-specific devices shall NOT be used as part of the horizontal cabling system, and they shall be kept external to the telecommunications outlet/connector and HC (FD).

Question 42

A passive optical network (PON) solution is suitable for deployment in a campus environment.

a. True
b. False

Answer 42

a. True

p 5-64

A PON solution is suitable for deployment in a campus environment because of the ability of the OLT to transmit and receive signals between ≈20.1 km (12.5 mi) and ≈60 km (37 mi).

Question 43

A conduit run is installed from the ER to a TR. It has two (2) 90 degree bend and a length of 20 m (65 ft). What will be the MINIMUM test rating of the pull cord left in the conduit?

a. 20 kg (44 lb)
b. 40 kg (88 lb)
c. 60 kg (132 lb)
d. 90 kg (200 lb)

Answer 43

d. 90 kg (200 lb)

Doesn’t matter on bends or length. Pull cord installed always need to have a minimum pull tensile strength of 200 ft lbs.

Question 44

You are designing a horizontal pathway system where you will provide 100 mm (4 in) conduit and pull boxes. The building architectural elements will only allow for a single layer of conduits (not stacked). The main horizontal pathway system consists of five 100 mm (4 in) conduits. Large single sheath copper cables are not expected to be placed. Which of the following is the MINIMUM width pull box that is to be provided?

a. 600 mm (24 in)
b. 900 mm (36 in)
c. 1220 mm (48 in)
d. 1520 mm (60 in)

Answer 44

c. 1220 mm (48 in)

p 5-83 Table 5.12

15” + ((4)x8”) = 47”

Question 45

You are designing a horizontal distribution system that will have a zone box located 71.6 m (235 ft) away from the telecommunications room (TR). A 50 mm (2 in) conduit is designed from the TR to a pull box located 36.6 m (120 ft) away from the TR. A 1 1/2 inch conduit is designed from the pull box to the zone box located 35.1 m (115 ft) beyond the pull box. Assuming no conduit bends, and excluding the TR and zone box, what is the total number of pull boxes/pull points required in this horizontal conduit system between the telecommunications room (TR) and zone box?

a. 2
b. 3
c. 4
d. 5

Answer 45

b. 3

Pull box at 100’ + pull box at 120’ + pull box at 220’ = Three (3) total

Pull points or pull boxes should be placed in sections of conduit that are ≈30.5 m (100 ft)

Question 46

Which type of cable tray is best described as a ventilated bottom with side rails?

a. Ventilated channel
b. Ladder
c. Spline
d. Ventilated trough

Answer 46

d. Ventilated trough

p 5-105 Table 5.17

Ventilated trough = A ventilated bottom with side rails

Question 47

In the ceiling zone method of distribution, the usable floor area should be divided into zones each measuring:

a. 9.3 sq m (100 sq ft) to 23 sq m (250 sq ft)
b. 23 sq m (250 sq ft) to 56 sq m (600 sq ft)
c. 23 sq m (250 sq ft) to 92.9 m2 (1000 ft2)
d. 56 sq m (600 sq ft) to 92.9 m2 (1000 ft2)

Answer 47

c. 23 sq m (250 sq ft) to 84 sq m (904 sq ft)

p 5-95

In the ceiling zones method of ceiling distribution, the usable floor area should be divided into zones of ≈23.2 m2 (250 ft2) to ≈92.9 m2 (1000 ft2) each.

Question 48

When placing an optical fiber cable in the horizontal optical fiber cabling subsystem, what is the MAXIMUM number of splices that can be used?

a. 1
b. 2
c. 3
d. 4

Answer 48

b. 2

p 5-16

When used in this manner, there shall be no more than two splices in the individual horizontal cabling channel. An additional two splices would be allowed if pigtail splicing connectors are located at a CP.

Question 49

On a project with three small conference rooms, a break room, and twelve private offices, what is the MINIMUM number of telecommunications outlet boxes required?

a. 16
b. 24
c. 40
d. 46

Answer 49

a. 16

p 5-22

Each work area shall have a minimum of ONE telecommunications outlet with a minimum of two recognized connectors per outlet

Question 50

Which of the following is NOT considered acceptable in an information technology system (ITS) conduit design and installation?

a. That do not contain continuous sections longer than ≈30.5 m (100 ft).
b. Bonded to ground on one or both ends in accordance with national or local code requirements
c. Will withstand the environment to which they were exposed
d. Uses flexible conduit to access wall outlets

Answer 50

d. Uses flexible conduit to access wall outlets

p 5-71

Question 51

When specifying telecommunications outlet boxes, all of the following should be considered EXCEPT:

a. Outlet box shall be a minimum of 100 mm (4 in) x 100 mm (4 in) x 76 mm (3 in)
b. Outlet boxes should be installed near an electric outlet at the same height
c. Different outlet boxes have different support requirements
d. Floor mounted telecom outlet boxes should be coordinated with furniture to minimize the potential trip hazard

Answer 51

a. Outlet box shall be a minimum of 100 mm (4 in) x 100 mm (4 in) x 76 mm (3 in)

p 5-22

The outlet box should be a minimum of ≈100 mm (4 in) × ≈100 mm (4 in) × ≈57 mm (2.25). This will accommodate one or two 27 mm (1 trade size) conduits.

Question 52

In a run requiring 15 m (50 ft) of cable between the floor distributor and the consolidation point, the MAXIMUM length of cable allowed between the CP and the telecommunications outlet is:

a. 27.4 m (90 ft)
b. 36.5 m (120 ft)
c. 45.8 m (150 ft)
d. 75 m (242 ft)

Answer 52

d. 75 m (242 ft)

p 5-17

Within the permanent link, the maximum cable length shall be no more than ≈90 m (295 ft) regardless of the type of transmission media used.

Question 53

Important considerations when designing telecommunications distribution within modular furniture include all of the following EXCEPT:

a. How the furniture pathways will be connected to horizontal building pathways
b. Separation of telecommunications cabling and electrical power
c. Diameter of cable to be installed
d. Maximum initial fill ratio of 40 percent when derated because of corners

Answer 53

d. Maximum initial fill ratio of 40 percent when derated because of corners

p 5-23

Question 54

Which of the following is NOT an example of a perimeter pathway?

a. Furniture pathways
b. Surface raceways
c. Multi channel raceways

Answer 54

a. Furniture pathways

p 5-110

Question 55

Using the conduit distribution system for horizontal cable distribution, how many cable runs are placed to serve 15 individual?

a. 15
b. 30
c. 45
d. 60

Answer 55

c. 45

p 5-80

3 cables per individual

Question 56

Assuming the total fill capacity of a pathway is 100 cables (all of the same cable type and size), the MAXIMUM number of cables to be installed during the initial installation, without exceeding the fill ratio is:

a. 25
b. 40
c. 50
d. 60

Answer 56

b. 40

p 5-76

40 percent initial fill factor

Question 57

When installing outlet boxes in 10 private offices in an area which may prove to be difficult to install future additional telecommunications outlets, the MINIMUM quantity of outlet boxes that should be installed is:

a. 10
b. 20
c. 30
d. Based on the type of cabling specified

Answer 57

b. 20

p 5-22

For work areas in which it may be difficult to install future additional telecommunications outlets/connectors (e.g., in private offices), a minimum of TWO telecommunications outlets should be provided and located for equipment access flexibility (e.g., on opposing walls).

Question 58

An open office design is made up of three furniture clusters and contains a total of nine work areas. How many multiuser telecommunications outlet assemblies (MUTOA) should be in the design?

a. 1
b. 3
c. 4
d. 6

Answer 58

b. 3

p 5-27

Each open office furniture cluster should be served by at least one MUTOA. A single MUTOA should be limited to serving a maximum of 12 work areas (all part of one furniture cluster), taking into account the maximum work area equipment cord length requirements.

Question 59

A furniture cluster with 26 requires a MINIMUM of how many multiuser telecommunications outlet assembly (MUTOA)?

a. 1
b. 2
c. 3
d. 4

Answer 59

c. 3

p 5-27

Each open office furniture cluster should be served by at least one MUTOA. A single MUTOA should be limited to serving a maximum of 12 work areas (all part of one furniture cluster), taking into account the maximum work area equipment cord length requirements.

or 26 / 12 ~ round up 2.167 ~ 3

Question 60

What type of fiber optic cable is manufactured to protect individual glass strands and is primarily designed for use inside buildings?

a. Ribbon
b. Tight buffered
c. Loose tube
d. Air blown

Answer 60

b. Tight buffered

p 6-22

It protects the optical fiber by supporting each strand of glass with a buffer coating extruded over the base optical fiber’s 250-μm acrylate coating.