(OLD) €h 06 - Backbone Distribution Systems

Question 1

6-4 Backbone Cross-connects

a backbone star topology =

Answer 1

two levels of cross-connects

Question 2

6-4 Backbone Cross-connects

connections between any two HCs =

Answer 2

not pass through (3) cross-connections

Question 3

6-7 Additional backbone connections between TR’s

Bus =

Answer 3

direct linear

Question 4

6-9 one-level hierarchical star campus backbone design

MC =
2

Answer 4

• close to (if not located in ) the main ER

* center of the building ~ 10th flr of 20th flr bldg

Question 5

6-11 connecting outlying bldg’s in a physical ring

physical ring =
2

Answer 5

• seldom recommended

* redundant cable path

Question 6

6-13 TR’s & ER’s

TR =
TE =
ER =

Answer 6

• architectural space
• a case
• environmentally controlled

Question 7

6-19 combined optical fiber & balanced twisted pair backbone

data systems =
voice systems =

Answer 7

• optical fiber

* twisted pair

Question 8

6-22 choosing optical fiber type

OM2 fiber =

Answer 8

1804ft 1Gb/s

Question 9

6-22 choosing optical fiber type

OM3 fiber =

Answer 9

984ft 10Gb/s

Question 10

6-22 choosing optical fiber type

Question/Answer
10G @ 286m =

Answer 10

OM3

Question 11

6-23 multimode optical fiber

multimode =

Answer 11

62.5/125 or 50/125

Question 12

6-23 singlemode optical fiber

singlemode =

Answer 12

1310/1550

Question 13

6-23 100ohm balanced twisted pair copper

building backbone =
campus backbone =

Answer 13

• 24 to 22 AWG

* 19 & 26 AWG

Question 14

6-23 performance categories of multipair backbone balanced twisted pair

2625ft backbone length =

Answer 14

voice systems

Question 15

6-25

vertically aligned =

Answer 15

TR

Question 16

6-25 vertically aligned TR’s

advantage TR’s =
2

Answer 16

• backbone is accessible

* circuits cab be distributed

Question 17

6-25 vertically aligned TR’s

sleeves or slots =

Answer 17

should not be directly above or below

Question 18

6-25 sleeves or slots

slots =
sleeves =

Answer 18

• 1 in. high curb

* 1 in. above the floor level

Question 19

6-26 sleeve quantity & configuration

inside (4) 4” =

Answer 19

add spare per 40,000 sqft

Question 20

6-26 sleeve quantity & configuration

50,000 sqt

Answer 20

(5) 4” backbone conduits

Question 21

6-27 slot quantity & config

slots =
2

Answer 21

• flush against the wall within space

* 6 - 24 in

Question 22

6-27 slot quantity & config

slot sized =

Answer 22

(5 sqft) up to 40,000 sqft

Question 23

6-28 open shafts

open shafts =

Answer 23

large quantities distant from the main ER

Question 24

6-28 avoid

do not locate backbone =

Answer 24

elevator shafts

Question 25

6-29 supporting strand

support strand suspended =

Answer 25

highest floor of the building and basement

Question 26

6-29 supporting strand

steel strands =

Answer 26

0.25 in

Question 27

6-29 supporting strand

insert cable ties =

Answer 27

before overall strand tensioning

Question 28

6-29 supporting strand

place the ties approx =

Answer 28

min. of three ties per floor

Question 29

6-33 sizing optical fiber backbone

most common application for optical fiber backbone cabling =

Answer 29

multiplexed transmission

Question 30

6-34 indoor hardware

indoor hardware =

Answer 30

varied

Question 31

6-39 optical fiber cable benefits

multimode =

Answer 31

cost effective tranceivers

Question 32

6-39 optical fiber composition

fiberglass rods or aramid yarn =

Answer 32

all-dielectric cables

Question 33

6-39 optical fiber composition

tight buffered fiber =
loose tube fiber =

Answer 33

• 900um used indoor

* 250um used outdoor

Question 34

6-42 min bend radius

non-conductive backbone =
2

Answer 34

• bend radius of 10 times under no load

* bend radius of 15 times being pulled

Question 35

6-42 min bend radius

conductive backbone =
2

Answer 35

• bend radius of 10 times under no load

* bend radius of 20 times being pulled

Question 36

6-42 max vertical rise

no load =

Answer 36

sitting on spool and final install

Question 37

6-45 multiple sheaths and splice points

additional sheaths =

Answer 37

not splicing

Question 38

6-47 methods to terminate

pigtail splicing =
2

Answer 38

• factory connectorized on one end

* unterminated at the other end

Question 39

6-48 pigtail splicing

pigtail splicing advantages =

Answer 39

factory-certified connector termination

Question 40

6-49 preconnectorized assemblies

preconnectorized assemblies disadvantages =

Answer 40

may be higher in price