Chapter 18 Flashcards
Availability
The long-term average of time
that a system is in service and is
satisfactorily performing its
intended function.
TDMM.* Page 18-28
Data Center
A building or portion of a
building whose primary function
is to house a computer room
and its support systems.
TDMM.* Page 18-1
HDA
Horizontal Distribution Area
A space in a computer room where a horizontal cross-connect HC is
located and may include LAN switches, storage area network (SAN) switches, and keyboard/video/mouse (KVM) switches for the end equipment located in the equipment distribution areas.
TDMM.* Page G-93
Information Security
The practice of protecting the
confidentiality, integrity, and
availability of data
and resources.
TDMM.* Page 18-24
MDA
Main Distribution Area
The space in an equipment
room where the main cross-
connect is located.
TDMM.* Page G-115
“N”
Need
Symbol used to represent “the
need” for redundancy in a
particular system.
TDMM.* Page 18-5
Reliability
The probability that a given
system will operate properly
without failure for a
given period of time.
TDMM.* Page 18-28
Redundancy
Providing secondary
components that either become
instantly operational or are
continuously operational so that
the failure of a primary
component will not result in
mission failure.
TDMM.* Page G-761
Name 2 advantages of
redundancy in a
data center.
1.lncreases fault tolerance
2.Increases maintainability
TDMM.* Page 18-4
Name 2 negative
consequences of adding
redundant components in
case of failures.
- Reduces efficiency
2.Increases losses
TDMM.* Page 18-4
What is an N-Base
A data center redundancy level
indicating that the system meets
base requirements and has
no redundancy
TDMM.* Page 18-5
What is N+1 redundancy?
A data center redundancy level
that provides one additional unit,
module, path, or system in
addition to the minimum
required to satisfy the
base requirement
TDMM.* Page 18-5
What is N+2 redundancy?
A data center redundancy level
that provides two additional
units, modules, paths, or
systems in addition to the
minimum required to satisfy
the base requirement
TDMM.* Page 18-5
What is 2N redundancy?
A data center redundancy level
that provides two complete
units, modules, paths, or
systems for each one required
for a base system
TDMM.* Page 18-5
What is 2(N+1)
redundancy?
A data center redundancy level
that provides two complete
(N+1) units, modules, paths,
or systems
TDMM.* Page 18-5
A data center has an N+l
redundancy level. Will
performing maintenance
on two units disrupt
operations?
Yes, an N+l redundancy level
allows for maintenance of a
single unit without disruption.
Therefore, performing
maintenance on two unit will
disrupt the system.
TDMM: Page 18-5
A data center has an N+2
redundancy level. Will the
failure of two modules
disrupt operations?
No, an N+2 redundancy level will
provide enough protection to
prevent disruption of operations.
TDMM.* Page 18-5
A data center has a 2N
redundancy level. Will the
failure of an entire unit
disrupt operations?
No, a 2N redundancy level will
provide enough protection to
prevent disruption of operations.
TDMM.* Page 18-5
A data center has an N-
Base requirement. Will the
failure of one path
disrupt operations?
Yes, the N-Base requirement
means that the system has no
redundancy, and the failure of
one path will disrupt operations.
TDMM.* Page 18-5
Name 4 areas of concern
that are used to define
data center facility
availability classes.
1 .Component redundancy
2.System redundancy
3.Quality control
4.Survivability
TDMM.* Page 18-5
How does component
redundancy increase
reliability?
By providing redundancy for
critical high-risk, low-reliability
components within systems
TDMM.* Page 18-5
How does survivability
increase reliability?
Protects against external events
such as physical forces, security
breaches, and natural disasters
TDMM.* Page 18-5
What is the objective of
availability class FO?
To support the basic
environmental and energy
requirements of the IT
functions without
supplementary equipment
TDMM.* Page 18-5
What is the objective of
availability class F1 ?
To support the basic
environmental and energy
requirements of the IT functions
TDMM.* Page 18-6
What is the objective of
availability class F2?
To provide a level of reliability
higher than that defined in class
F1 to reduce the risk of
downtime because of
component failure
TDMM.* Page 18-6
Which units receive
redundancy in a
class F2 facility?
Critical components
TDMM.* Page 18-7
What is the objective of
availability class F3?
To provide additional reliability
and maintainability to reduce the
risk of downtime because of
natural disasters, human-driven
disasters, planned maintenance,
and repair activities
TDMM.* Page 18-7
What is the objective of
availability class F4?
To eliminate downtime through
the application of all tactics to
provide continuous operation
regardless of planned or
unplanned activities
TDMM.* Page 18-8
Name two prime
requirements for a
class F4 facility.
1 . Compartmentalization
2. Fault tolerance
TDMM.* Page 18-8
What is the targeted
availability of a
class F4 facility?
99.999 percent
TDMM.* Page 18-8
What is the separation
requirement between
balanced twisted-pair
cables and electrical
branch circuits?
=600 mm (2 ft)
TDMM: Page 18-17
What is the separation
requirement between
balanced twisted-pair
cables and
fluorescent lamps?
-12.5 mm (5 in)
TDMM: Page 18-17
Name 3 means of properly
placing underfloor cabling.
1 .Laying it on a suitably sealed
floor
2.Placing it on foam matting
3.Housing it in a basket raceway
TDMM: Page 18-22
How can additional
physical protection be
added to cable trays that
house telecommunications
cabling?
Use solid trays or
armored cables.
TDMM.* Page 18-22
Name 3 negative
consequences of
unmanaged patch cord
slack in the data center.
1 .Significantly impedes or blocks air flow, increasing temperatures
2.Increases the time required to maintain or change equipment
configurations in racks
3.Increases time to identify and replace poor or non-functioning
cable
TDMM.* Page 18-23
Name 5 factors that
determine the type and
amount of patch cord slack
management used in a
data center.
1 .Specific configuration of cabinets
and racks
2.Use of overhead or underfloor
cabling
3.Location of air intake and outlets for
the equipment
4.Type of cabling media being used
5.Style of equipment panel in use
TDMM.* Page 18-23
How is the loss or
destruction of property
typically defined?
By the value of the property and
the cost associated with
replacing that property
TDMM.* Page 18-24
Name the 7 classes of
potential for damage
or loss.
- Temperature
- Gases
- Liquids
- Organisms
- Projectiles
- Movement
- Energy anomalies
TDMM: Page 18-25
What is the most
significant physical threat
to the reliable operation of
the data center?
Human beings
TDMM.* Page 18-25
What are the 4 concentric
layers for data center
physical security?
1 .Site security
2.Perimeter security
3.Building and access control
4.Computer room security
TDMM.* Page 18-26, Figure 18.8
Name 5 security factors
that affect the selection of
a potential site for a
data center.
1 .Crime
2.Emergency services
3. Telecommunications
4.UtiIities
5.NaturaI disasters
TDMM.* Page 18-26
Name 4 benefits of using
security perimeter
measures.
1 .Delay to allow alarms or other
detection systems to activate
2.Evidence of an intrusion or an
intrusion attempt
3.PhysioIogical discouragement
4.Mitigates damage from the
threat
TDMM: Page 18-27
Name the 3 primary factors
used to identify and
authenticate a
user’s identity.
1 .Something a person knows
(e.g., password)
2.Something a person has
(e.g., keys)
3.Something a person is
(e.g., biometrics)
TDMM: Page 18-27
What is an additional,
optional authentication
factor that a data center
can use to control access?
Something a person does
TDMM.* Page 18-27
Name the 4 categories of
security spaces as defined
by the practice of crime
prevention through
environmental engineering.
1 .Public space
2.Semipublic space
3.Semiprivate space
4.private space
TDMM.* Page 18-27
Why should a designer
ensure that a kitchenette is
NOT adjacent to the
computer room?
If pipes in the kitchenette leak,
the water could spill into the
computer room.
TDMM.* Page 18-28
If an existing computer
room has a door on its
outside wall, what security
measures should be
considered?
*Traditional alarm sensors
Physical barriers such as bars
and plates
TDMM. Page 18-29
How much overpressure is
required to shatter
tempered safety glass?
5.5 kilopascals
(0.8 pounds per square inch)
TDMM: Page 18-29
What provides the greatest
opportunity to improve
energy efficiency?
HVAC efficiency
TDMM.* Page 18-30
When should lighting be on
in the data center?
Only when work is
being performed
TDMM.* Page 18-30
Name 3 reasons windows
and skylights should
be avoided in a
computer room.
1 .Create potential security risk
2.Provide minimal useful lighting
3.Create a heat load, resulting in
more energy loss than energy
savings
TDMM.* Page 18-30
How should you determine
how much capacity is
required for the data
center’s cabling
containment system?
You will need to determine how
much capacity will be adequate
for the cabling requirements of
the data center when it is fully
built-out and occupied.
TDMM.* Page 18-36
What component can be
installed in an empty space
in a cabinet or rack to
support the hot and cold
aisle strategy?
Blanking panels
TDMM.* Page 18-37
Where should lighting be
installed in the data center?
Above the aisles
TDMM.* Page 18-37
