Chapter 4 Flashcards
Backbone Distribution
System
The part of the premises
distribution system that provides
connection between
telecommunications spaces.
TDMM.* Page 4-1
CO
Central Office
A common carrier switching center
office (also called public exchange)
that is conveniently located in areas to
serve subscriber homes and
businesses. It provides telephony
services (lines) that are connected on
a local loop. The CO contains
switching equipment that can switch
calls locally or to long-distance carrier
telephone offices.
TDMM.* Page G-34
EF
Entrance Facility
An entrance to a building for both
public and private network service
cables (including wireless),
including the entrance point of the
building and continuing to the
entrance room or space. (TIA)
TDMM: Page 4-1, Table 4.1
EFM
Ethernet in the Fist Mile
Term used to describe the
access network from the access
point to the subscriber’s
premises. Also referred to as
Ethernet in the last mile.
TDMM.* Page 4-53
ER
Equipment Room
An environmentally controlled
centralized space for
telecommunications equipment
that usually houses a main or
immediate cross-connect. (T IA)
TDMM.* Page 4-1, Table 4.1
HC (FD)
Horizontal Cross-Connect
(Floor Distributor)
A group of connectors that allow
equipment and backbone
cabling to be cross-connected or
interconnected with patch cords
or jumpers to horizontal cabling.
TDMM.* Page 4-2, Table 4.1
IC (BD)
Intermediate Cross-Connect
(Building Distributor)
The connection point between a
backbone cable that extends
from the MC (CD) [first-level
backbone] to the HC (FD)
[second-level backbone].
TDMM.* Page 4-2, Table 4.7
MC (CD)
Main Cross-Connect
(Campus Distributor)
The cross-connect normally
located in the (main) equipment
room for cross-connection and
interconnection of entrance
cables, first level backbone
cables, and equipment cables.
TDMM.* Page 4-2, Table 4.1
RMC
Rigid Metallic Conduit
A threaded metal raceway of
circular cross-section With
a coupling. RMC is the heaviest-
weight and thickest-wall steel
conduit.
TDMM: Page 4-42
TE
Telecommunications Enclosure
A case or housing that may
contain telecommunications
equipment, cable terminations,
or horizontal cross-connect
cabling. (TIA)
TDMM.* Page 4-1, Table 4.1
TR
Telecommunications Room
An enclosed architectural space
for housing telecommunications
equipment, cable terminations,
and cross-connect cabling. (T IA)
TDMM.* Page 4-7, Table 4.1
Name the 2 typical
functions a backbone
system provides
in a campus.
1 .Building connections between
floors in multi-story buildings
2.Campus connections in multi-
building environments
TDMM.* Page 4-1
Name 7 components of a
backbone distribution
system.
1 .Cable pathways
2. ERs that may contain HCs (FDs),
ICs (BDs), or MCs (CDs)
3.TRs that typically contain HCs (FDs)
4.TEs that typically contain HCs (FDs)
5.Entrance facility (EF)
6.Transmission media
7.Miscellaneous support facilities
TDMM: Page 4-1
Which component of the
backbone distribution
system provides routing
space for cables?
Cable pathways
TDMM.* Page 4-1, Table 4.1
Which component of a
backbone distribution
system usually houses the
main cross-connect (MC)?
Equipment room (ER)
TDMM.* Page 4-1, Table 4.1
Which component of a
backbone distribution
system is described as an
enclosed architectural
space for housing
telecommunications
equipment, cable
terminations, or horizontal
cross-connect cabling?
Telecommunications room (T R)
TDMM.* Page 4-1, Table 4.1
Which component of a
backbone distribution
system is described as a
case or housing that may
contain telecom equipment,
cable terminations, or
horizontal cross-connect
cabling?
Telecommunications enclosure
TDMM: Page 4-1, Table 4.1
Which component of the
backbone distribution
system serves as an
entrance to the building for
both public and private
network service cables?
Entrance facility (EF)
TDMM.* Page 4-1, Table 4.1
Name the 4 primary types
of transmission media that
can be used for backbone
cabling.
1 .Optical fiber
2.Balanced twisted-pair
3.Coaxial
4.Wireless
TDMM.* Page 4-2, Table 4.1
Name 5 examples of
connecting hardware that
can be used as
components of a backbone
distribution system.
1 .Connecting blocks
2.Patch panels
3.Patch cords and jumpers
4.Interconnections
5.Cross-connections
TDMM.* Page 4-2, Table 4.1
Name 4 examples of
miscellaneous support
materials that are needed
for the proper termination
and facilities installation of
backbone cables.
1 .Cable support hardware
2.Firestop
3.Bonding hardware
4.Protection and security
TDMM.* Page 4-2, Table 4.1
What term refers to a group of
connectors that allow
equipment and backbone
cabling to be cross-connected
or interconnected with patch
cords or jumpers to horizontal
cabling?
Horizontal Cross-Connect (HC)/
Floor Distributor (FD)
TDMM.* Page 4-2, Table 4.1
Which component serves as
the connection point between
the first level backbone and the
second
level backbone?
Intermediate Cross-Connect (IC)/
Building Distributor (BD)
TDMM: Page 4-2, Table 4.1
Which component is normally
located in the main ER for the
cross-connection and
interconnection of entrance
cables, first level backbone
cables, and equipment cables?
Main Cross-Connect (MC)/
Campus Distributor (CD)
TDMM.* Page 4-2, Table 4.1
Name the 3 fundamental
cabling topologies.
1 .Star
2.Ring
3.Bus
TDMM.* Page 4-3
Name 5 types of hybrid
cabling topologies.
1 .Hierarchical star
2.Star-wired ring
3.Clustered star
4. Tree and branch
5.Mesh
TDMM.* Page 4-3
What topology is generally
deployed for OSP cabling?
Star
TDMM: Page 4-4
A star topology directly
links all buildings requiring
connection to the ____
MC (CD)
TDMM.* Page 4-4
What is the ideal location
for the MC (CD)
*Colocated with or close to the
primary ER
At the center of the buildings
being served.
TDMM. Page 4-4
Name 5 advantages
associated with using a
star topology for campus
backbone cabling.
1 .Provides centralized facilities
administration
2.Allows testing and reconfiguration
of the systems topology and
applications from the MC (CD)
3.Allows easy maintenance and
security against unauthorized access
4.Provides increased flexibility
5.Allows the easy addition of future
campus backbones
TDMM.* Page 4-4
Name 2 disadvantages
associated with using a
star topology for campus
backbone cabling.
1 .lntroduces single points of
failure
2.Increases cost
TDMM.* Page 4-4
What term is used to
describe the tree-like
structure where a trunk and
branch relationship exists
within a cabling topology?
Hierarchical
TDMM.* Page 4-6
True or False
The link from the MC (CD)
to the IC (BD) may be an
interbuilding or an
intrabuilding link.
True. The link from the MC (CD)
to the IC (BD) may be an
interbuilding or an
intrabuilding link.
TDMM.* Page 4-6
What type of link is typically
found between the IC (BD)
and the HC (FD)?
An intrabuilding link
TDMM.* Page 4-6
What configuration should
the ICT designer consider
when the distance from the
switch to the last
workstation exceeds the
transmission limit?
Hierarchical star
TDMM.* Page 4-7
What type of configuration
should the ICT designer
consider using when
available pathways do not
allow for all cables to be
routed to an MC (CD)?
Two-level hierarchical star
TDMM.* Page 4-7
Why are ring topologies
being used for OSP
operations?
Because they can support
high-bandwidth transport
applications
TDMM.* Page 4-8
Name 3 benefits associated with using a ring topology.
1 .FauIt-tolerant redundant routing
2.Greater reliability and significantly less cabling service downtime
3.Flexible architecture
TDMM.* Page 4-8
What 3 conditions must be
met before a physical ring
topology can be considered
for connecting the
intrabuilding ICs (BDs)
and MCs (CDs)?
1 . The existing pathways must
support it.
2. The primary purpose of the
network is optical fiber distributed
data interface, SONET, token ring,
or reverse path Ethernet.
3. There is a redundant cable path.
TDMM.* Page 4-9
When would a physical
star/logical ring be used?
*When OSP designer determines
that a physical ring route is not
possible
When an existing cable will be
used in a segment of the total
project
TDMM. Page 4-11
Name 3 factors the ICT
designer will use to
determine if a clustered
star topology is an
appropriate solution.
1 .Electronics
2.Designer’s survivability plans
3. Transmission budget selected
at the MC (CD) and each node
site
TDMM.* Page 4-12