ISO/IEC TS 22237-5:2018

TECHNICAL ISO/IEC TS
SPECIFICATION 22237-5
First edition
2018-05
Information technology — Data centre
facilities and infrastructures —
Part 5:
Telecommunications cabling
infrastructure
Technologie de l’information — Installation et infrastructures de
centres de traitement de données —
Partie 5: Infrastructure du câblage dédié télécommunications
Reference number
©
ISO/IEC 2018
© ISO/IEC 2018
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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Published in Switzerland
ii © ISO/IEC 2018 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and abbreviations . 2
3.1 Terms and definitions . 2
3.2 Abbreviated terms . 3
4 Conformance . 4
5 Telecommunications cabling within the data centre . 4
5.1 General . 4
5.1.1 The importance of telecommunications cabling within data centre spaces . 4
5.1.2 Cabling implementation . 5
5.1.3 Point-to-point cabling. 5
5.1.4 Fixed cabling . 6
5.2 Information technology and network telecommunications cabling in the computer
room space . 7
5.2.1 General. 7
5.2.2 Generic cabling for data centre information technology equipment . 8
5.2.3 Generic cabling for office network information technology equipment . 9
5.2.4 Generic cabling for monitoring and control . 9
5.2.5 Application-specific fixed cabling .10
5.3 Structured cabling for other data centre spaces and application-specific structured
cabling .10
5.3.1 General.10
5.3.2 Application-specific cabling using a fixed infrastructure .10
6 Availability design principles for telecommunications cabling infrastructure .11
7 Availability classification for telecommunications cabling infrastructure .11
7.1 General .11
7.2 Telecommunications cabling for the computer room .12
7.2.1 Cabling for Availability Class 1 . .12
7.2.2 Cabling for Availability Class 2 . .13
7.2.3 Cabling for Availability Class 3 . .14
7.2.4 Cabling for Availability Class 4 . .15
7.3 Telecommunications cabling for offices .16
7.4 Telecommunications cabling for monitoring and control .16
8 Pathways and pathway systems for telecommunications cabling .16
8.1 General .16
8.2 Pathways .17
8.2.1 External service pathways .17
8.2.2 Data centre pathways .17
8.3 Pathway systems .18
8.3.1 Requirements for data centre pathway systems .18
8.3.2 Access floor tile openings .18
8.3.3 Cable management systems .18
9 Cabinets and racks for the computer room space .19
9.1 General requirements .19
9.2 Requirements for dimensions.19
9.3 Recommendations .19
10 Documentation and quality plan .20
10.1 Requirements for documentation .20
© ISO/IEC 2018 – All rights reserved iii

10.2 Recommendations for documentation .20
10.3 Requirements for the quality plan .20
11 Management and operation of the telecommunications cabling infrastructure .20
11.1 General .20
11.2 Automated infrastructure management systems .20
11.3 Fibre optic cabling.20
Annex A (normative) Cabling design concepts .21
Annex B (informative) Energy efficiency considerations for the telecommunications cabling
infrastructure .29
Bibliography .30
iv © ISO/IEC 2018 – All rights reserved

Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are
members of ISO or IEC participate in the development of International Standards through technical
committees established by the respective organization to deal with particular fields of technical
activity. ISO and IEC technical committees collaborate in fields of mutual interest. Other international
organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the
work. In the field of information technology, ISO and IEC have established a joint technical committee,
ISO/IEC JTC 1.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for
the different types of document should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject
of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent
rights. Details of any patent rights identified during the development of the document will be in the
Introduction and/or on the ISO list of patent declarations received (see www .iso .org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following
URL: www .iso .org/iso/foreword .html.
This document was prepared by Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 39, Sustainability for and by Information Technology.
A list of all parts in the ISO/IEC TS 22237 series can be found on the ISO website.
© ISO/IEC 2018 – All rights reserved v

Introduction
The unrestricted access to internet-based information demanded by the information society has led to
an exponential growth of both internet traffic and the volume of stored/retrieved data. Data centres
are housing and supporting the information technology and network telecommunications equipment
for data processing, data storage and data transport. They are required both by network operators
(delivering those services to customer premises) and by enterprises within those customer premises.
Data centres need to provide modular, scalable and flexible facilities and infrastructures to easily
accommodate the rapidly changing requirements of the market. In addition, energy consumption of data
centres has become critical both from an environmental point of view (reduction of carbon footprint)
and with respect to economical considerations (cost of energy) for the data centre operator.
The implementation of data centres varies in terms of:
a) purpose (enterprise, co-location, co-hosting or network operator facilities);
b) security level;
c) physical size;
d) accommodation (mobile, temporary and permanent constructions).
The needs of data centres also vary in terms of availability of service, the provision of security and
the objectives for energy efficiency. These needs and objectives influence the design of data centres
in terms of building construction, power distribution, environmental control and physical security.
Effective management and operational information is required to monitor achievement of the defined
needs and objectives.
The ISO/IEC TS 22237 series specifies requirements and recommendations to support the various
parties involved in the design, planning, procurement, integration, installation, operation and
maintenance of facilities and infrastructures within data centres. These parties include:
1) owners, facility managers, ICT managers, project managers, main contractors;
2) architects, building designers and builders, system and installation designers;
3) facility and infrastructure integrators, suppliers of equipment;
4) installers, maintainers.
At the time of publication of this document, the ISO/IEC TS 22237 series will comprise the following
documents:
ISO/IEC TS 22237-1, Information technology — Data centre facilities and infrastructures — Part 1: General
concepts
ISO/IEC TS 22237-2, Information technology — Data centre facilities and infrastructures — Part 2:
Building construction
ISO/IEC TS 22237-3, Information technology — Data centre facilities and infrastructures — Part 3: Power
distribution
ISO/IEC TS 22237-4, Information technology — Data centre facilities and infrastructures — Part 4:
Environmental control
ISO/IEC TS 22237-5, Information technology — Data centre facilities and infrastructures — Part 5:
Telecommunications cabling infrastructure
ISO/IEC TS 22237-6, Information technology — Data centre facilities and infrastructures — Part 6:
Security systems
vi © ISO/IEC 2018 – All rights reserved

ISO/IEC TS 22237-7, Information technology — Data centre facilities and infrastructures — Part 7:
Management and operational information
The inter-relationship of the specifications within the ISO/IEC TS 22237 series is shown in Figure 1.
Figure 1 — Schematic relationship between the ISO/IEC TS 22237 series of documents
ISO/IEC TS 22237-2 to ISO/IEC TS 22237-6 specify requirements and recommendations for particular
facilities and infrastructures to support the relevant classification for “availability”, “security” and
“energy efficiency enablement” selected from ISO/IEC TS 22237-1.
This document addresses the specific requirements for the telecommunications cabling infrastructure
in data centres used for the purpose of IT networking and building services (in accordance with the
requirements of ISO/IEC TS 22237-1).
ISO/IEC TS 22237-7 addresses the operational and management information (in accordance with the
requirements of ISO/IEC TS 22237-1.
This document is intended for use by and collaboration between architects, building designers and
builders, system and installation designers.
The ISO/IEC TS 22237 series does not address the selection of information technology and network
telecommunications equipment, software and associated configuration issues.
© ISO/IEC 2018 – All rights reserved vii

TECHNICAL SPECIFICATION ISO/IEC TS 22237-5:2018(E)
Information technology — Data centre facilities and
infrastructures —
Part 5:
Telecommunications cabling infrastructure
1 Scope
This document addresses the wide range of telecommunications cabling infrastructures within data
centres based upon the criteria and classifications for “availability” within ISO/IEC TS 22237-1.
This document specifies requirements and recommendations for the following:
a) information technology and network telecommunications cabling (e.g. SAN and LAN);
b) general information technology cabling to support the operation of the data centre;
c) telecommunications cabling to monitor and control, as appropriate, power distribution,
environmental control and physical security of the data centre;
d) other building automation cabling;
e) pathways, spaces and enclosures for the telecommunications cabling infrastructures.
Safety and electromagnetic compatibility (EMC) requirements are outside the scope of this document
and are covered by other standards and regulations. However, information given in this document may
be of assistance in meeting these standards and regulations.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO/IEC 11801-1, Information technology — Generic cabling systems — Part 1: General requirements
ISO/IEC 11801-2, Information technology — Generic cabling systems — Part 2: Office premises
ISO/IEC 11801-5, Information technology — Generic cabling systems — Part 5: Data centres
ISO/IEC 11801-6, Information technology — Generic cabling systems — Part 6: Distributed building
services
ISO/IEC 14763-2, Information technology — Implementation and operation of customer premises
cabling — Part 2: Planning and installation
ISO/IEC TS 22237-1:2018, Information technology — Data centre facilities and infrastructures — Part 1:
General concepts
ISO/IEC TS 22237-2, Information technology — Data centre facilities and infrastructures — Part 2:
Building construction
ISO/IEC TS 22237-4, Information technology — Data centre facilities and infrastructures — Part 4:
Environmental control
© ISO/IEC 2018 – All rights reserved 1

ISO/IEC TS 22237-7, Information technology — Data centre facilities and infrastructures — Part 7:
Management and operational information
3 Terms, definitions and abbreviations
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC TS 22237-1 and the
following apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http: //www .electropedia .org/
— ISO Online browsing platform: available at https: //www .iso .org/obp
3.1.1
application-specific cabling
structured cabling with a configuration and performance which is considered to provide a specific
benefit for a single, or limited number of applications, as compared to generic cabling
3.1.2
central patching location
passive cross-connect to connect different functional elements of a data centre
Note 1 to entry: A central patching location can be located in the main distribution area and/or the intermediate
distribution area and is therefore a special configuration of an MD and/or an ID.
3.1.3
cross-connect
method of connecting a patch panel port to another patch panel port by the use of a patch cord or jumper
3.1.4
data centre information technology equipment
equipment in the computer room space of a data centre that transports and/or stores and/or processes
information
3.1.5
fixed cabling
cabling subsystem between closures which has either a peer-to-peer or hierarchical structure and
which enables the installation of cross-connects or interconnects at those closures
3.1.6
generic cabling
structured telecommunications cabling system, capable of supporting a wide range of applications
Note 1 to entry: Application-specific hardware is not a part of generic cabling.
Note 2 to entry: Generic cabling can be installed without prior knowledge of the required applications.
[SOURCE: ISO/IEC 11801-1:2017, 3.1.46 — modified: Notes 1 and 2 to entry added]
3.1.7
interconnect
method of connecting a patch panel port to an equipment port by the use of equipment cords
3.1.8
office network information technology equipment
equipment in data centre spaces that transports and/or stores and/or processes information
2 © ISO/IEC 2018 – All rights reserved

3.1.9
point-to-point connection
direct connection of two pieces of IT equipment using a dedicated cable rather than a generic
cabling system
3.1.10
structured cabling
telecommunications cabling comprising fixed cables between points of distribution at which equipment
or other fixed cables may be connected
3.1.11
telecommunications provider
either an access provider or a service provider
3.1.12
zone patching location
passive cross-connect to connect different function elements of a data centre zone
Note 1 to entry: A zone patching location can be located in the zone distribution area and is therefore a special
configuration of a ZD.
3.2 Abbreviated terms
For the purposes of this document, the abbreviated terms given in ISO/IEC TS 22237-1 and the following
abbreviated terms apply.
BEF Building Entrance Facility
BD Building Distributor
Connection
C
CD Campus Distributor
CP Consolidation Point
CPL Central Patching Location
ENI External Network Interface
EO Equipment Outlet
EoR End of Row
EQP Transmission Equipment
FD Floor Distributor
ID Intermediate Distributor
LDP Local Distribution Point
MD Main Distributor
MoR Middle of Row
SCP Service Concentration Point
SD Service Distributor
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SO Service Outlet
TE Terminal Equipment
TO Telecommunications Outlet
ToR Top of Rack
ZD Zone Distributor
ZPL Zone Patching Location
4 Conformance
For a data centre to conform to this document:
a) the cabling design shall meet the requirements of Clause 5;
b) the cabling design for the selected Availability Class shall be in accordance with Clause 7;
c) the design and specifications of pathways and spaces shall be in accordance with Clauses 8 and 9;
d) the information technology cabling to support the operation of the data centre shall be in
accordance with ISO/IEC 11801-2, except where 7.3 allows an alternative approach;
e) the information technology cabling to support the IT networking function of the data centre shall
be in accordance with ISO/IEC 11801-5, except where 7.2 allows an alternative approach;
f) telecommunications cabling for monitoring and/or control of power distribution, environmental
control and physical security shall be in accordance with ISO/IEC 11801-6, except where 7.4 allows
an alternative approach;
g) installation specification, quality assurance, installation planning and practice of cabling shall be
in accordance with ISO/IEC 14763-2 and Clauses 8 and 9;
h) national and local regulations, including safety, shall be met.
5 Telecommunications cabling within the data centre
5.1 General
5.1.1 The importance of telecommunications cabling within data centre spaces
The telecommunications cabling within the data centre serves to support the following:
a) data centre information technology and network telecommunications;
b) monitoring and controlling of other data centre infrastructures;
c) building management and automation.
The design and planning of cabling infrastructures should be undertaken at an early stage of the data
centre design or refurbishment and should be integrated with the design and planning of:
1) electrical power;
2) environmental control systems;
3) security systems;
4 © ISO/IEC 2018 – All rights reserved

4) lighting systems.
This clause defines the requirements and recommendations for the performance, design criteria and
architectures for the different cabling types in a data centre.
The importance of the information technology and network telecommunications cabling infrastructure
is similar to that of other infrastructures such as environmental control, power distribution and security.
As with other utilities, interruptions to service can have a serious impact. Poor quality of service due
to lack of planning, use of inappropriate components, incorrect installation, poor administration or
inadequate support can threaten an organization's effectiveness.
5.1.2 Cabling implementation
The cabling infrastructures in a data centre shall be appropriate to provide networking and
telecommunications capabilities in and between dedicated data centre spaces.
For the purposes of this document, two types of cabling are considered for data centre spaces:
a) point-to-point;
b) fixed cabling implemented using structured cabling including the generic cabling solutions of the
ISO/IEC 11801 series. The closures may be grouped and accommodated in cabinets, frames or racks
which act as cabling presentation facilities. The cabling presentation facilities allow interconnection
or cross-connections between fixed cabling or between fixed cabling and IT equipment in close
proximity.
5.1.3 Point-to-point cabling
5.1.3.1 General
The point-to-point connection method uses discrete cords (typically factory-produced) that directly
connect the active equipment. Each cord connects a single port of one device to a single port of
another device.
Although point-to-point cabling seems to be the simplest and most cost effective method of providing
connections, for several reasons this cabling type should only be used for connections within the
same or two adjacent cabinets, frames or racks. Point-to-point cabling is often not reusable as the data
centre evolves and equipment types and locations change and may have a limited life time expectation.
Continuous changes to the required interconnections increase both the planning and the operational
resources required for each change (see Figure 2 and Figure 3) and increases the risk of interfering
with other infrastructures — including those for environmental control.
5.1.3.2 Restrictions on the use of point-to-point cabling
Where this document allows point-to-point cabling, it should only be used subject to the following
restrictions:
a) the mechanical performance of cords or cables used for point-to-point connections shall meet the
requirements of the installation environment (e.g. pathway systems);
b) connectors on cords shall be protected against damage during installation, disconnection or
removal;
c) point-to-point connections shall only be used where the replacement of the cord following damage
to either connector can be performed without disruption to the data centre operation;
d) cords shall be managed so as to avoid mechanical damage and/or accidental disconnection to
adjacent connections during insertion or removal;
© ISO/IEC 2018 – All rights reserved 5

e) cords shall be labelled at both ends to show their origin and destination in accordance with the
level 3 administration requirements of ISO/IEC 14763-2;
f) the impact of point to point connections on the fire load of cabling shall be assessed and mitigation
provided if necessary;
g) cords providing point-to-point connections shall not be located where they restrict cooling airflow
towards active equipment.
Figure 2 — Impact of growth in an unstructured point-to-point cabling infrastructure
Figure 3 — Example of point-to-point cabling
5.1.4 Fixed cabling
A structured cabling system approach, illustrated in Figure 4, shows the equipment ports presented at
remote central patching locations (CPLs). Server-to-storage connections are made using short, easily
6 © ISO/IEC 2018 – All rights reserved

managed, cords within the CPL. The use of distributed zone patching locations (ZPL), connected to the
CPLs with fixed cables provides additional flexibility for managing changes.
Figure 4 shows how a fixed cabling implementation isolates the change activity to the defined areas.
New equipment is connected to a CPL or ZPL without impacting active systems so no scheduled
downtime is required. The equipment can then be connected to the active systems during the scheduled
downtime by simply reconfiguring the cords at the CPL or ZPL. If a change causes a problem, it is only
necessary to reconnect the cords into their pre-change configuration. The structured approach enables
more accurate predictions of the time required to implement system changes and recovery resulting in
easier, faster changes that introduce less risk and enable improved overall system operation.
Fixed cables may have a greater minimum bending radius than cords and this shall be considered in
pathway and pathway system design and planning.
Figure 4 — Structured cabling infrastructure: setup and growth
5.2 Information technology and network telecommunications cabling in the computer
room space
5.2.1 General
The cabling infrastructures in a data centre shall be appropriate to provide networking and
telecommunications capabilities in and between many of the dedicated data centres spaces. The cabling
infrastructure described in this clause is that between and within the cabinets, frames and racks which
constitute the computer room space and may take one of, or a combination of, the following forms:
a) point-to-point;
© ISO/IEC 2018 – All rights reserved 7

b) fixed:
1) generic — structured cabling in accordance with ISO/IEC 11801-5 for IT and network
telecommunications;
2) generic — structured cabling in accordance to ISO/IEC 11801-2 for IT and network
telecommunications;
3) generic — structured cabling in accordance with ISO/IEC 11801-6 for monitoring and control;
4) application specific cabling.
The chosen infrastructure strategy shall take into account the need to support existing and future
networking and storage applications and significant amounts of change.
5.2.2 Generic cabling for data centre information technology equipment
Generic cabling infrastructure designs in accordance with the ISO/IEC 11801 series are based upon
a defined cabling model and support the development of high data rate applications. ISO/IEC 11801-
5 defines generic cabling to provide multiple services and to connect large quantities of equipment
within the limited space of data centre premises, and shall be used together with ISO/IEC 11801-1.
Information technology cabling to support the operation of the data centre shall be in accordance with
ISO/IEC 11801-5.
Figure 5 shows the cabling subsystem architecture of ISO/IEC 11801-5.
Figure 5 — Data centre cabling subsystems according to ISO/IEC 11801-5
Generic cabling in accordance with ISO/IEC 11801-5 uses pre-defined pathways and spaces that are
specifically intended to support changing demands and provides:
a) scalability via a modular design;
b) a greater level of flexibility with equipment moves, adds and changes;
c) a level of consistency with generic cabling design methodology for other services such as power
supply distribution and environmental control;
d) the support for a wide range of applications in the data centre.
Generic cabling systems are intended to avoid the impact of the uncontrolled use of point-to-point cables
described in 5.1.3.2 by using fixed cables within defined cable pathways between panels (patch panel)
at designated patching locations. This greatly simplifies cabling modifications by managing changes at
8 © ISO/IEC 2018 – All rights reserved

the patching locations rather than disconnecting, moving and reconnecting discrete cables under the
floor or in ceiling spaces.
5.2.3 Generic cabling for office network information technology equipment
Information technology cabling to support the operation of the data centre shall be in accordance with
ISO/IEC 11801-2.
Figure 6 shows the cabling subsystem architecture of ISO/IEC 11801-2.
Figure 6 — Office cabling subsystems according to ISO/IEC 11801-2
5.2.4 Generic cabling for monitoring and control
ISO/IEC 11801-6 specifies generic cabling that supports a wide range of communication services within
premises. It reflects the increasing use of generic cabling in support of non-user specific services,
including the monitoring and control of data centre infrastructures. Many of these services require the
use of remote powered devices and include:
a) energy management as described in ISO/IEC TS 22237-3, e.g. lighting, power distribution, incoming
utility metering;
b) environmental control as described in ISO/IEC TS 22237-4, e.g. temperature, humidity;
c) personnel management as described in ISO/IEC TS 22237-6, e.g. access control, cameras, motion/
proximity detectors, time and attendance monitoring.
Cabling for these purposes shall be in accordance with ISO/IEC 11801-6.
Figure 7 shows the cabling subsystem architecture of ISO/IEC 11801-6.
© ISO/IEC 2018 – All rights reserved 9

Figure 7 — Building service cabling subsystem according to ISO/IEC 11801-6
5.2.5 Application-specific fixed cabling
In cases where data centre owners agree to the use of application-specific cabling because of advantages
compared with generic cabling, those application-specific cabling systems shall have a fixed and
structured infrastructure approach in accordance with the cabling subsystem architecture of ISO/
IEC 11801-5 (see Figure 5).
5.3 Structured cabling for other data centre spaces and application-specific
structured cabling
5.3.1 General
The cabling infrastructures in a data centre shall be appropriate to provide networking and
telecommunications capabilities in and between many of the dedicated data centres spaces. The cabling
infrastructure between and within the data centre spaces other than the computer room space shall
take one or more of the following forms:
a) generic — structured cabling in accordance with ISO/IEC 11801-2 for IT and network
telecommunications (see 5.2.3);
b) generic — structured cabling in accordance with ISO/IEC 11801-6 for monitoring and control
(see 5.2.4);
c) application specific (see 5.3.2).
5.3.2 Application-specific cabling using a fixed infrastructure
In cases where data centre owners agree to the use of application-specific cabling because of advantages
compared with generic cabling, those application-specific cabling systems shall have a fixed and
structured infrastructure approach in accordance with the cabling subsystem architecture of ISO/
IEC 11801-2 (see Figure 6).
10 © ISO/IEC 2018 – All rights reserved

6 Availability design principles for telecommunications cabling infrastructure
ISO/IEC TS 22237-1:2018, Annex A, gives guidance about design principles for availability. This
document uses the principles of:
a) redundancy;
b) maintainability;
c) scalability/future proofness;
d) simplicity.
as a basis for the design of:
1) the telecommunications cabling itself;
2) the telecommunications architecture;
3) associated pathways and spaces.
in order to achieve the desired Availability Class for the telecommunications infrastructure as described
in Clause 6.
Redundancy within the networks of the data centre shall be implemented by means of the active
equipment without the need for manual interaction. All redundancy implementations within the cabling
(e.g. multi-path routeing; Classes 3 and 4) are in support of that provided by active equipment.
7 Availability classification for telecommunications cabling infrastructure
7.1 General
This clause classifies the architecture and the redundancy concept of all telecommunications cabling
infrastructures as it relates to the chosen overall Availability Class for facilities and infrastructures of
the data centre according to ISO/IEC TS 22237-1.
Table 1 defines the minimum requirements for all telecommunications cabling types in the different
data centre spaces to achieve the chosen overall Availability Class of the data centre as defined by ISO/
IEC TS 22237-1. All defined Availability Classes for the different cabling types and spaces shall be met in
order to achieve the chosen overall data centre Availability Class for facilities and infrastructures.
Table 1 — Telecommunication cabling Availability Classes per space architecture and overall
data centre Availability Class for facilities and infrastructures
Data centre Cabling type Overall data Overall data Overall data Overall data
space centre facilities centre facilities centre facilities centre facilities
and infrastruc- and infrastruc- and infrastruc- and infrastruc-
ture — Availabili- ture — Availabili- ture — Availabili- ture — Availabili-
ty Class 1 ty Class 2 ty Class 3 ty Class 4
Computer Inter- 7.2.1 7.2.2 7.2.3 7.2.4
room space cabinets
Class 1 Class 2 Class 3 Class 4
Intra- 7.2.1 7.2.1 7.2.1 7.2.1
cabinets
Class 1 Class 1 Class 1 Class 1
Adjacent 7.2.1 7.2.1 7.2.1 7.2.1
cabinets
Class 1 Class 1 Class 1 Class 1
Monitoring 7.4 7.4 7.4 7.4
and Control
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Table 1 (continued)
Data centre Cabling type Overall data Overall data Overall data Overall data
space centre facilities centre facilities centre facilities centre facilities
and infrastruc- and infrastruc- and infrastruc- and infrastruc-
ture — Availabili- ture — Availabili- ture — Availabili- ture — Availabili-
ty Class 1 ty Class 2 ty Class 3 ty Class 4
Office style 7.3 7.3 7.3 7.3
cabling
Control Office style 7.3 7.3 7.3 7.3
room space cabling
Monitoring 7.4 7.4 7.4 7.4
and Control
Other spaces Office Style 7.3 7.3 7.3 7.3
Monitoring 7.4 7.4 7.4 7.4
and Control
7.2 Telecommunications cabling for the computer room
7.2.1 Cabling for Availability Class 1
A telecommunications cabling infrastructure for Availability Class 1 uses either a point-to-point
connection (i.e. equipment cords) for the transmission channel (see Figure 8) or a fixed cabling
infrastructure (see Figure 9) in a single-path configuration as shown in Figure 10.
Figure 8 — Telecommunication cabling Class 1 using direct attached cords
Figure 9 — Transmission channels (interconnect and cross-connect)
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The point-to-point connections shall use pre-terminated cords and shall be restricted to local
connections within the same cabinet or between adjacent cabinets, frames and racks.
Figure 10 — ENI redundancy for Class 1 and 2
7.2.2 Cabling for Availability Class 2
A telecommunications cabling infrastructure for Availability Class 2 shall use a fixed cabling
infrastructure (e.g. according to ISO/IEC 11801-5 or application-specific) in cabling subsystems defined
in ISO/IEC 11801-5 for the transmission channel design (see Figure 9) with a single-path architecture
with redundancy on the ENI as shown in Figure 10. The pathways for the telecommunications providers
shall be designed according to Clause 8.
Furthermore, the following design criteria shall be met:
a) the design shall be flexible and scalable to allow quick moves, adds and changes by using central
and local patching/cross connect locations in MD, ID and ZD as shown in Figure 11;
b) the patching/cross-connect cabinets/frames/racks used in MD and/or ID (CPL) and ZD (ZPL)
shall offer rear cable management and side patch cord management. The design and selection of
cross-connect cabinets/frames/racks shall take into consideration the maximum planned cabling
capacity and required density inside the cabinets/frames/racks with the objective of minimising
the disruption of airflow to active equipment. One possible and preferred way of achieving this
functionality is to increase the width of the cabinets/frames/racks to offer more space for cable
and patch cords which simplifies operations for moves, adds and changes.
c) where it is intended to create channels from more than a single subsystem via cross-connects
in distributors, the selection of media and component performance shall take into account the
impact of the number of connections within, and the total length of, the channels in relation to the
applications which are intended to be supported.
© ISO/IEC 2018 – All rights reserved 13

Figure 11 — Managing moves, adds and changes
7.2.3 Cabling for Availability Class 3
A telecommunications cabling infrastructure for Availability Class 3 shall use a fixed cabling
infrastructure (e.g. according to ISO/IEC 11801-5 or application-specific) in cabling subsystems
defined in ISO/IEC 11801-5 for the transmission channel design (see Figure 9) with a multi-path
redundancy configuration using diverse physical pathways as shown in Figure 12. The pathways for
the telecommunications providers shall be designed according to Clause 8.
Figure 12 — Redundant multipath telecommunication cabling Class 3
14 © ISO/IEC 2018 – All rights reserved

Furthermore, the following design criteria shall be met:
a) the design shall be flexible and scalable to allow quick moves, adds and changes by using central
and local patching/cross connect locations in MD, ID and
...