* Chapter 4 - Backbone Distribution Systems Flashcards
What is a backbone distribution system?
The part of a premises distribution system that provides connection between telecom spaces (ie MDF IDF DMarc). Typically connects between floors in multistory buildings, multi-buildning environments (Campus Backbone)
Three types of Topologies
Star
Ring
Tree
Star topology
Each building is connected to one main building
OM1 Distance
2000m (6500’)
OM2 Distance
550m (1800’)
OM3 Distance
300m (1800’) 10Gb/s … 100m (328’) 100Gb/s
OM4 Distance
550m (1804’) 10Gb/s … 150m (492’) 100 Gb/s
OS1 Distance
10,000m (32,808’) 100 Gb/s
OS2 Distance
10,000 (32,808’) 100Gb/s
Types of steel conduit used for pathways
RMC - Rigid Metal Conduit
IMC - Intermediate Metal Conduit
EMT - Electrical Metallic Tubing
RMC - Rigid Metal Conduit
Threaded metal raceway. This is the heaviest and thickest of the steel conduits. When galvanized, it typically has a coating of zinc on both sides. Galvanized makes it noncombustible and can be used indoors, outdoors, underground, concealed or exposed.
IMC - Intermediate Metal Conduit
Threaded similar to RMC though IMC is about one third the weight and is thinner.
EMT - Electrical Metallic Tubing
Also known as thin-wall. Unthreaded conduit. This is the lightest weight steel conduit and easiest to alter in the field (bends). Not recommended for use in underground or exterior applications because of its poor resistance to corrosion.
PON
Passive Optical Network. Typically a point to multi point fiber to the premises network architecture in which unpowered optical splitters are used to enable a single fiber to serve multiple premises.
Other names for this are.. fiber to the edge, fiber to the home, fiber to the building, fiber to the curb
Sleeve used for backbone distribution should be located a minimum of ____ from adjacent sleeves.
1”
Ideally, the Main Crossconnect (MC) (Campus Distributer (CD)) would be co-located in the:
(ER) Equipment Room
In a backbone distribution system, connections between any two floor distributors shall not pass through more than ___ cross-connection(s).
Three
A backbone distribution shall not have more than ___ levels of cross connections.
2
What color identifies the first level of interbuilding backbone?
Brown
This is the backbone going from the main cross connect of one building to the the horizontal cross connect of another building
What color identifies the first level intrabuilding backbone? (intrabuilding refers to within the same building)
White
First level intrabuilding backbone refers to backbone going from Main cross connect to Intermediate Cross Connect or Horizontal Cross Connect.
What color identifies the second level intrabuilding backbone?
Gray
Second level intrabuilding backbone refers to backbone going from Intermediate Crossconnect to Horizontal Cross connect
In Ethernet over digital subscriber line (EoDSL) networks, 2Mb/s service (2PASS-TL) can be provided to subscribers over a maximum span of ____ using balanced twisted pair cable.
8858ft
Sleeves used for backbone distribution should be constructed to extend a minimum of __ and a maximum of ___ above the floor level.
Minimum of 1in
Max of 3in
A minimum of ___ sleeves are required for floor to floor backbone distribution with an addition one sleeve per ____.
4 sleeves
additional sleeve per 40,000 sq ft
A typical floor slot for backbone distribution should have a minimum depth of ___ and a minimum length of ____.
Minimum depth of 6in
Minimum length of 10in
A typical floor slot for backbone distribution should have a maximum depth of ___ .
24in
Slots used for backbone distribution should be sized at ___ per 40,000 sq ft and increased by ___ per additional 40,000sq ft of usable space.
60 in sq per 40,000 sq ft
increased by 12 in sq per additional 40,000 sq ft
The maximum balanced twisted-pair backbone length for voice systems should not exceed:
2625ft
Also, total length between network equipment connections should not be greater than 328ft.
What are the advantages of using a star topology for the campus backbone cabling?
- Provides centralized facilities administration
- Allows testing and reconfiguration of the systems topology and applications from the MC (CD)
- Allows easy maintenance and security against unauthorized access
- Provides increased flexibility
- Allows the easy addition of future campus backbones
