Ansi Tia 942 B 33719

ANSI/TIA-942-B-2017 APPROVED: JULY 12, 2017

Telecommunications Infrastructure Standard for Data Centers

TIA-942-B (Revision of TIA-942-A)

July 2017

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ANSI/TIA-PN-942-B

Telecommunications Infrastructure Standard for Data Centers Table of Contents 1

SCOPE .................................................................................................................................. 1

2

NORMATIVE REFERENCES................................................................................................ 1

3

DEFINITION OF , ACRONYMS AND ABBREVIATIONS, AND UNITS OF MEASURE ............................................................................................................................. 2

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3.1 3.2 3.3 3.4 4

General.............................................................................................................................. 2 Definition of ............................................................................................................. 2 Acronyms and abbreviations ............................................................................................. 7 Units of measure ............................................................................................................... 8 DATA CENTER DESIGN OVERVIEW .................................................................................. 9

4.1 4.2 4.3 4.4

General.............................................................................................................................. 9 Relationship of data center spaces to other building spaces............................................ 9 Availability and Security .................................................................................................. 10 Consideration for involvement of professionals .............................................................. 11

5

DATA CENTER CABLING SYSTEM INFRASTRUCTURE ............................................... 12

6

DATA CENTER TELECOMMUNICATIONS SPACES AND RELATED TOPOLOGIES ... 15 6.1 General............................................................................................................................ 15 6.2 Data center structure....................................................................................................... 15 6.2.1 Major elements ........................................................................................................ 15 6.2.2 Basic data center topology ...................................................................................... 16 6.2.3 Reduced data center topologies .............................................................................. 17 6.2.4 Distributed data center topologies ........................................................................... 17 6.2.5 Topologies for broadband coaxial cabling ............................................................... 18 6.3 Energy efficient design .................................................................................................... 18 6.3.1 General .................................................................................................................... 18 6.3.2 Energy efficiency recommendations ........................................................................ 19 6.4 Common requirements for computer rooms and entrance rooms .................................. 22 6.4.1 General .................................................................................................................... 22 6.4.2 Architectural design ................................................................................................. 22 6.4.3 Environmental design .............................................................................................. 24 6.4.4 Electrical design ....................................................................................................... 24 6.4.5 Fire protection .......................................................................................................... 25 6.4.6 Water infiltration ....................................................................................................... 25 6.4.7 Access ..................................................................................................................... 25 6.5 Computer room requirements ......................................................................................... 25 6.5.1 General .................................................................................................................... 25 6.5.2 Location ................................................................................................................... 26 6.5.3 Environmental design - HVAC ................................................................................. 26 6.5.4 Electrical design ....................................................................................................... 26 6.6 Entrance room requirements........................................................................................... 26 6.6.1 General .................................................................................................................... 26

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ANSI/TIA-PN-942-B 6.6.2 Location ................................................................................................................... 26 6.6.3 Quantity .................................................................................................................... 26 6.6.4 Entrance conduit routing under access floor ........................................................... 27 6.6.5 Access provider and service provider spaces ......................................................... 27 6.6.6 Building entrance terminal ....................................................................................... 27 6.6.7 Architectural design ................................................................................................. 27 6.7 Main distribution area ...................................................................................................... 28 6.7.1 General .................................................................................................................... 28 6.7.2 Location ................................................................................................................... 28 6.7.3 Facility requirements ................................................................................................ 28 6.8 Intermediate distribution area ......................................................................................... 28 6.8.1 General .................................................................................................................... 28 6.8.2 Location ................................................................................................................... 29 6.8.3 Facility requirements ................................................................................................ 29 6.9 Horizontal distribution area ............................................................................................. 29 6.9.1 General .................................................................................................................... 29 6.9.2 Location ................................................................................................................... 29 6.9.3 Facility requirements ................................................................................................ 29 6.10 Zone distribution area ..................................................................................................... 29 6.11 Equipment distribution areas .......................................................................................... 29 6.12 Telecommunications room .............................................................................................. 30 6.13 Data center areas............................................................................................... 30 6.14 Cabinets and racks ......................................................................................................... 30 6.14.1 General .................................................................................................................... 30 6.14.2 "Hot" and "cold" aisles ............................................................................................. 30 6.14.3 Placement relative to floor tile grid........................................................................... 31 6.14.4 Access floor tile cuts ................................................................................................ 31 6.14.5 Installation of racks on access floors ....................................................................... 32 6.14.6 Racks and cabinets in entrance room, MDAs, IDAs and HDAs .............................. 32 7

DATA CENTER CABLING SYSTEMS ............................................................................... 33

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7.1 General............................................................................................................................ 33 7.2 Choosing media .............................................................................................................. 33 7.2.1 General .................................................................................................................... 33 7.2.2 Cable fire rating requirements ................................................................................. 33 7.3 Horizontal Cabling ........................................................................................................... 33 7.3.1 General .................................................................................................................... 33 7.3.2 Topology .................................................................................................................. 34 7.3.3 Horizontal cabling length ......................................................................................... 34 7.3.4 Direct attach cabling ................................................................................................ 34 7.3.5 Recognized media ................................................................................................... 35 7.3.6 Optical fiber connectors ........................................................................................... 35 7.3.7 Coaxial cable connectors ......................................................................................... 35 7.4 Backbone cabling ............................................................................................................ 36 7.4.1 General .................................................................................................................... 36 7.4.2 Topology .................................................................................................................. 36 7.4.3 Redundant cabling topologies ................................................................................. 37 7.4.4 Recognized media ................................................................................................... 37 7.4.5 Optical fiber connectors ........................................................................................... 38 7.4.6 Coaxial cable connectors ......................................................................................... 38 7.4.7 Backbone cabling lengths ........................................................................................ 38 7.5 Centralized optical fiber cabling ...................................................................................... 38 7.5.1 General .................................................................................................................... 38 7.5.2 Implementation ........................................................................................................ 38 7.6 Cabling transmission performance and test requirements ............................................. 38 7.6.1 General .................................................................................................................... 38 ii

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ANSI/TIA-PN-942-B 7.6.2 8

Additional requirements for field testing of 75-ohm coaxial cabling ........................ 38

DATA CENTER CABLING PATHWAYS ............................................................................ 40 8.1 General............................................................................................................................ 40 8.2 Security for data center cabling ...................................................................................... 40 8.3 Routing of telecommunications cables ........................................................................... 40 8.3.1 Separation between power or lighting and balanced twisted-pair cables................ 41 8.3.2 Separation of fiber and balanced twisted-pair cabling ............................................. 41 8.4 Telecommunications entrance pathways ........................................................................ 41 8.4.1 Entrance pathway types .......................................................................................... 41 8.4.2 Diversity ................................................................................................................... 41 8.4.3 Sizing ....................................................................................................................... 41 8.5 Access floor systems ...................................................................................................... 42 8.5.1 General .................................................................................................................... 42 8.5.2 Access floor performance requirements .................................................................. 42 8.5.3 Floor tile cut edging.................................................................................................. 42 8.6 Cable trays ...................................................................................................................... 42 8.6.1 General .................................................................................................................... 42 8.6.2 Cable trays in access floor systems ........................................................................ 43 8.6.3 Overhead cable trays ............................................................................................... 43 8.6.4 Coordination of cable tray routes ............................................................................. 43

9

DATA CENTER REDUNDANCY ........................................................................................ 44 9.1 9.2 9.3 9.4 9.5 9.6 9.7

Introduction ..................................................................................................................... 44 Redundant maintenance holes and entrance pathways ................................................. 45 Redundant access provider services .............................................................................. 45 Redundant entrance room .............................................................................................. 45 Redundant main distribution area ................................................................................... 46 Redundant backbone cabling ......................................................................................... 46 Redundant horizontal cabling ......................................................................................... 46

10

CABLING INSTALLATION REQUIREMENTS ................................................................... 46

11

CABLING TRANSMISSIONG PERFORMANCE REQUIREMENTS ................................. 46

12

CABLING FOR INTELLIGENT BUILDING SYSTEMS ...................................................... 46

13

CABLING FOR WIRELESS ACCESS POINTS ................................................................. 46

14

CABLING FOR DISTRIBUTED ANTENNA SYSTEMS...................................................... 46

15

POWER DELIVERY OVER BALANCED TWISTED-PAIR CABLING ............................... 46

16

GROUNDING AND BONDING............................................................................................ 46

17

FIRESTOPPING .................................................................................................................. 47

18

PHYSICAL SECURITY ....................................................................................................... 47

19

ISTRATION .............................................................................................................. 47

ANNEX A

(INFORMATIVE) CABLING DESIGN CONSIDERATIONS.................................... 49

A.1 Application cabling lengths.............................................................................................. 49 A.1.1 T-1, E-1, T-3 and E-3 circuit lengths ........................................................................ 49 A.1.2 Baluns E-3 and T-3 circuits ...................................................................................... 51

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ANSI/TIA-PN-942-B A.1.3 TIA-232 and TIA-561 console connections ............................................................. 52 A.2 Cross-connections .......................................................................................................... 53 A.3 Separation of functions in the main distribution area ...................................................... 53 A.3.1 Twisted-pair main cross-connect ............................................................................. 53 A.3.2 Coaxial main cross-connect ..................................................................................... 53 A.3.3 Optical fiber main cross-connect ............................................................................. 53 A.4 Separation of functions in the horizontal distribution area .............................................. 54 A.5 Cabling to end equipment ............................................................................................... 54 A.6 Fiber design consideration .............................................................................................. 54 A.7 Balanced twisted-pair design consideration.................................................................... 54 ANNEX B

(INFORMATIVE) ACCESS PROVIDER INFORMATION ....................................... 55

B.1 Access provider coordination .......................................................................................... 55 B.1.1 General .................................................................................................................... 55 B.1.2 Information to provide to access providers .............................................................. 55 B.1.3 Information that the access providers should provide ............................................. 55 B.2 Access provider demarcation in the entrance room ....................................................... 56 B.2.1 Organization............................................................................................................. 56 B.2.2 Demarcation of low-speed circuits ........................................................................... 56 B.2.3 Demarcation of T-1 circuits ...................................................................................... 59 B.2.4 Demarcation of E-3 & T-3 circuits ............................................................................ 59 B.2.5 Demarcation of optical fiber circuits ......................................................................... 60 ANNEX C (INFORMATIVE) COORDINATION OF EQUIPMENT PLANS WITH OTHER ENGINEERS ........................................................................................................................ 61 ANNEX D

(INFORMATIVE) DATA CENTER SPACE CONSIDERATIONS............................ 62

E.1 E.2 E.3 E.4 E.5 E.6 E.7

General............................................................................................................................ 63 Architectural site selection and building design considerations ...................................... 63 Electrical site selection and building design considerations ........................................... 63 Mechanical site selection and building design considerations........................................ 64 Telecommunications site selection and building design considerations ......................... 64 Security site selection and building design considerations ............................................. 64 Other site selection considerations ................................................................................. 65

ANNEX F

(INFORMATIVE) DATA CENTER INFRASTRUCTURE RATING ......................... 66

F.1 General ................................................................................................................................ 66 F.1.1 Redundancy overview ................................................................................................... 66 F.1.2 Overview ....................................................................................................................... 66 F.2 Redundancy .................................................................................................................... 66 F.2.1 N - Base requirement ............................................................................................... 66 F.2.2 N+1 redundancy ...................................................................................................... 67 F.2.3 N+x redundancy ....................................................................................................... 67 F.2.4 2N or N+N redundancy ............................................................................................ 67 F.2.5 2(N+1) redundancy .................................................................................................. 67 F.2.6 Concurrent maintainability and testing capability .................................................... 67 F.2.7 Fault tolerant ............................................................................................................ 67 F.2.8 Capacity and scalability ........................................................................................... 67 F.2.9 Isolation .................................................................................................................... 67 F.2.10 Data center rating .................................................................................................... 67 F.3 Telecommunications ....................................................................................................... 68 F.3.1 I Data Center: Basic (telecommunications) ............................................................. 68 F.3.2 II Data Center: Redundant Component (telecommunications) ................................ 69 iv Provided by IHS No reproduction or networking permitted without license from IHS

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ANNEX E (INFORMATIVE) DATA CENTER SITE SELECTION AND BUILDING DESIGN CONSIDERATIONS ............................................................................................................ 63

ANSI/TIA-PN-942-B

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F.3.3 III Data Center: Concurrently Maintainable (telecommunications) .......................... 69 F.3.4 IV Data Center: Fault Tolerant (telecommunications) ............................................. 70 F.4 Architectural and structural ............................................................................................. 71 F.4.1 General .................................................................................................................... 71 F.4.2 I Data Center: Basic (architectural).......................................................................... 71 F.4.3 II Data Center: Redundant Component (architectural) ............................................ 71 F.4.4 III Data Center: Concurrently Maintainable (architectural) ...................................... 71 F.4.5 IV Data Center: Fault Tolerant (architectural) .......................................................... 71 F.5 Electrical .......................................................................................................................... 71 F.5.1 I Data Center: Basic (electrical) ............................................................................... 71 F.5.2 II Data Center: Redundant Component (electrical) ................................................. 72 F.5.3 III Data Center: Concurrently Maintainable (electrical) ............................................ 72 F.5.4 IV Data Center: Fault Tolerant (electrical) ............................................................... 73 F.6 Mechanical systems ........................................................................................................ 73 F.6.1 I Data Center: Basic (mechanical) ........................................................................... 73 F.6.2 II Data Center: Redundant Component (mechanical) ............................................. 73 F.6.3 III Data Center: Concurrently Maintainable (mechanical) ........................................ 74 F.6.4 IV Data Center: Fault Tolerant (mechanical) ........................................................... 74 ANNEX G G.1 G.2 G.3

(INFORMATIVE) DATA CENTER DESIGN EXAMPLES ....................................... 88

Small data center design example .................................................................................. 88 Corporate data center design example ........................................................................... 89 Internet data center design example............................................................................... 91

ANNEX H

(INFORMATIVE) CABLING GUIDELINES FOR DATA CENTER FABRICS ........ 94

H.1 Traditional Switch Architecture ....................................................................................... 94 H.2 Multiple Connections ....................................................................................................... 96 H.3 Data Center Switch Fabrics ............................................................................................ 97 H.3.1 Data center fabric fat-tree ........................................................................................ 97 H.3.2 Data center fabric full-mesh ................................................................................... 101 H.3.3 Data center fabric inter-connected meshes ........................................................... 103 H.3.4 Data center fabric centralized switch ..................................................................... 104 H.3.5 Data center fabric virtual switch ............................................................................. 106 ANNEX I

(INFORMATIVE) BIBLIOGRAPHY ....................................................................... 108

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ANSI/TIA-PN-942-B

List of figures Figure 1: Illustrative relationship between the ANSI/TIA-568 Series and other relevant TIA standards ................................................................................................................................... x  Figure 2: Relationship of spaces in a data center ......................................................................... 10  Figure 3: Functional elements of generic cabling topology ........................................................... 12  Figure 4: Examples of interconnections and cross-connections for Distributor A ......................... 13  Figure 5: Example of a typical data center topology ..................................................................... 14  Figure 6: Example of a basic data center topology ....................................................................... 16  Figure 7: Example of a reduced data center topology................................................................... 17  Figure 8: Example of a distributed data center topology with multiple entrance rooms ................ 18  Figure 9: Examples of routing cables and air flow contention ....................................................... 20  Figure 10: Example of "hot" aisles, "cold" aisles and cabinet placement...................................... 31  Figure 11: Tile cuts should not be where it touches any of the lines on a cross formed by the corners of the tile .................................................................................................................... 32  Figure 12: Typical horizontal cabling using a star topology .......................................................... 34  Figure 13: Typical backbone cabling using a star topology .......................................................... 37  Figure 14: Telecommunications cabling pathway and space redundancy .................................... 44  Figure 15: Cross-connection circuits to IDC connecting hardware cabled to modular jacks in the T568A 8-pin sequence ........................................................................................................... 57  Figure 16: Cross-connection circuits to IDC connecting hardware cabled to modular jacks in the T568B 8-pin sequence ........................................................................................................... 58  Figure 17: Computer room layout showing “hot” and “cold” aisles................................................ 88  Figure 18: Example of corporate data center ................................................................................ 90  Figure 19: Example of Internet data center ................................................................................... 92  Figure 20: Example of traditional three-tier data center switch architecture ................................. 94  Figure 21: Example of ANSI/TIA-942-B cabling topology ............................................................. 95  Figure 22: Examples of redundant connectivity ............................................................................ 96  Figure 23: Fat-tree example .......................................................................................................... 97  Figure 24: Fat-tree with port extenders example........................................................................... 98  Figure 25: Example of use of structured cabling for fat-tree switch architecture .......................... 99  Figure 26: Interconnected fat-tree pods example........................................................................ 100  Figure 27: Full-mesh example ..................................................................................................... 101  Figure 28: Example of use of structured cabling for full-mesh switch architecture ..................... 102  Figure 29: Interconnected meshes example ............................................................................... 103  Figure 30: Example of use of structured cabling for interconnected mesh fabric ....................... 104  Figure 31: Centralized switch example ....................................................................................... 104  Figure 32: Example of use of structured cabling for centralized switch fabric ............................ 105  Figure 33: Virtual switch example................................................................................................ 106  Figure 34: Example of cabling for fabric virtual switch architecture ............................................ 107 

List of tables Table 1: Conduit sizes ..................................................................................................................... 3  Table 2: Maximum Coaxial Cable Insertion Loss .......................................................................... 39  Table 3: Maximum circuit lengths with no DSX ................................................................... 49  Table 4: Reduction in circuit lengths for DSX ...................................................................... 49  Table 5: Reduction in circuit lengths per connection or outlet ....................................................... 50  Table 6: Maximum circuit lengths for the typical data center configuration................................... 51  Table 7: Maximum backbone length for the typical data center configuration .............................. 51  Table 8: Maximum circuit lengths over baluns NOT including insertion loss of baluns ................ 52  vi --`,,```,,,,````-`-`,,`,,`,`,,`---

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ANSI/TIA-PN-942-B Table 9: Reduction in maximum circuit length for each 1 dB insertion loss for a pair of baluns ... 52  Table 10: Reduction in maximum circuit length for each additional twisted-pair connection (after the 1st two) ............................................................................................................................. 52  Table 11: Reference guide (telecommunications) ......................................................................... 75  Table 12: Reference guide (architectural) ..................................................................................... 76  Table 13: Reference guide (electrical) .......................................................................................... 82  Table 14: Reference guide (mechanical) ...................................................................................... 86 

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ANSI/TIA-PN-942-B

FOREWORD (This foreword is not considered part of this Standard.) This Standard was developed by TIA Subcommittee TR-42.1.

Approval of this Standard This Standard was approved by the Telecommunications Industry Association (TIA) Subcommittee TR 42.1, TIA Technical Engineering Committee TR 42, and the American National Standards Institute (ANSI). ANSI/TIA reviews standards every 5 years. At that time, standards are reaffirmed, revised, or withdrawn according to the submitted updates. Updates to be included in the next revision of this Standard should be sent to the committee chair or to TIA.

Contributing organizations More than 60 organizations within the telecommunications industry (including manufacturers, consultants, end s, and other organizations) contributed their expertise to the development of this Standard.

Documents superseded This Standard replaces ANSI/TIA-942-A dated August 2012 and its addenda. This Standard incorporates the technical content of ANSI/TIA-942-A, Addendum 1, Cabling Guidelines for Data Center Fabrics

Major modifications from ANSI/TIA-942-A The major modifications in ANSI/TIA-942-B from ANSI/TIA-942-A include: 

Added MPO-16 and MPO-32 (ANSI/TIA-604-18) and MPO-24 (ANSI/TIA-604-5) as options for termination of more than two fibers in addition to the MPO-12 connector



Added category 8 as an allowed type of balanced twisted-pair cable. Changed recommendation for category 6A balanced twisted-pair cable to category 6A or higher.



Added OM5 as an allowed and recommended type of multimode fiber cable.



Added 75-ohm broadband coaxial cables and connectors as ANSI/TIA-568.4-D as allowed types of coaxial cables and connectors.



Added recommendation to not install optical fiber cords and cables (both bend insensitive and non-bend insensitive) without adequate armoring or sufficiently thick jacket in pathways that can create microbends, such as non-continuous cable s, wire basket trays, and cable ladders without radiused cable s or solid bottoms.



Reduced quantity of convenience outlets required on computer room walls.



Local fire protection codes may be used instead of NFPA 75.



Power for air conditioning systems and controls in computer rooms and entrance rooms should be redundant, but do not need to be powered from the same PDUs or boards that serve ICT equipment in the room.



Recommended maximum cable lengths for direct attach cabling in EDAs has been reduced from 10 m (33 ft) to 7 m (23 ft). Additional guidance added that direct attach cabling between rows is not recommended.



Added recommendation that cabinets be at 1200 mm (48”) deep and to consider cabinets wider than 600 mm (24”) wide. viii --`,,```,,,,````-`-`,,`,,`,`,,`---

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specified

in

ANSI/TIA-PN-942-B 

Added recommendation to consider preterminated cabling to reduce installation time and improve consistency and quality of terminations.



Added recommendation to consider needs for proper labeling, cable routing, cable management, and ability to insert and remove cords without disrupting existing or adjacent connections.



Adds normative reference to ANSI/TIA-5017 regarding physical security for the data center telecommunications infrastructure.



Adds normative reference to ANSI/TIA-862-B regarding requirements for cabling for intelligent building systems including networked data center electrical, mechanical, and security equipment.



Added reference to TIA TSB 162-A for guidelines regarding cabling for wireless access points in data centers



Added reference to TIA TSB-5018 for guidelines regarding cabling for distributed antenna systems in data centers.



Added reference to TIA TSB-184-A for guidelines regarding power delivery over balanced twisted-pair cabling.



Numerous changes to the rating tables in Annex F including those that specify concurrent maintainability for Rating-3 (formerly Tier 3) and fault tolerance for Rating-4 (formerly Tier 4).

Relationship to other TIA standards and documents The following are related standards regarding various aspects of structured cabling that were developed and are maintained by Engineering Committee TIA TR-42. An illustrative diagram of the ANSI/TIA-568 Series relationship to other relevant TIA standards is given in figure 1. --`,,```,,,,````-`-`,,`,,`,`,,`---



ANSI/TIA-568.0‐D, Generic Telecommunications Cabling for Customer Premises



ANSI/TIA-568.1‐D, Commercial Building Telecommunications Infrastructure Standard



ANSI/TIA-568-2.C, Balanced Twisted-Pair Telecommunications Cabling and Components standard



ANSI/TIA-568.3‐D, Optical Fiber Cabling and Components Standard



ANSI/TIA-568.4.D, Broadband Coaxial Cabling and Components Standard



ANSI/TIA-569-D, Telecommunications Pathways and Spaces



ANSI/TIA-606-C, istration Standard for Telecommunications Infrastructure



ANSI/TIA-607-C, Telecommunications Bonding and Grounding (Earthing) for Customer Premises



ANSI/TIA-758-B, Standard



ANSI/TIA-862-B, Structured Cabling Infrastructure Standard for Intelligent Building Systems



ANSI/TIA-5017, Telecommunications Physical Network Security Standard

Customer-Owned

Outside

Plant

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Telecommunications

Infrastructure

ANSI/TIA-PN-942-B

Common Standards

ANSI/TIA-568.0 (Generic) ANSI/TIA-569 (Pathways and spaces)

Premises Standards

Cabling & Component Standards

ANSI/TIA-568.1 (Commercial)

ANSI/TIA-568.2 (Balanced twistedpair)

ANSI/TIA-570 (Residential)

ANSI/TIA-568.3 (Optical fiber)

ANSI/TIA-606 (istration)

ANSI/TIA-758 (Outside plant) ANSI/TIA-862 (Intelligent building systems) ANSI/TIA-5017 (Physical network security)

ANSI/TIA-568.4 (Broadband coaxial)

ANSI/TIA-1005 (Industrial)

ANSI/TIA-1179 (Healthcare)

ANSI/TIA-4966 (Educational)

Figure 1: Illustrative relationship between the ANSI/TIA-568 Series and other relevant TIA standards The following documents may also be useful to the reader: 

National Electrical Safety Code® (NESC®) (IEEE C 2-2012)



National Electrical Code® (NEC®) (NFPA 70-2014)

Useful supplements to this Standard are the BICSI Telecommunications Distribution Methods Manual, the Outside Plant Design Reference Manual, and the Information Transport Systems Installation Methods Manual. These manuals provide recommended practices and methods by which many of the requirements of this Standard may be implemented. Other references are listed in Annex I.

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--`,,```,,,,````-`-`,,`,,`,`,,`---

ANSI/TIA-607 (Bonding and grounding [earthing])

ANSI/TIA-942 (Data centers)

ANSI/TIA-PN-942-B

Annexes There are nine annexes to this Standard. Annexes A, B, C, D, E, F, G, H and I are informative and not considered to be requirements of this Standard.

Purpose of this Standard The purpose of this Standard is to provide requirements and guidelines for the design and installation of a data center or computer room. It is intended for use by designers who need a comprehensive understanding of the data center design, including the facility planning, the cabling system, and the network design. The standard will enable the data center design to be considered early in the building development process, contributing to the architectural considerations, by providing information that cuts across the multidisciplinary design efforts, promoting cooperation in the design and construction phases. Adequate planning during building construction or renovation is significantly less expensive and less disruptive than after the facility is operational. Data centers in particular can benefit from infrastructure that is planned in advance to growth and changes in the computer systems that the data centers are designed to . This document presents an infrastructure topology for accessing and connecting the respective elements in the various cabling system configurations currently found in the data center environment. In order to determine the performance requirements of a generic cabling system, various telecommunications services and applications were considered. In addition, this document addresses the floor layout related to achieving the proper balance between security, rack density, and manageability. The standard specifies a generic telecommunications cabling system for the data center and related facilities whose primary function is information technology. Such application spaces may be dedicated to a private company or institution, or occupied by one or more service providers to host Internet connections and data storage devices. Data centers a wide range of transmission protocols. Some of these transmission protocols impose length restrictions that are shorter than those imposed by this Standard. Consult standards, regulations, equipment vendors, and system service suppliers for: applicability, limitations, and ancillary requirements when applying specific transmission protocols. Consider consolidating standardized and proprietary cabling into a single structured cabling system. Data centers can be categorized according to whether they serve the private domain (“enterprise” data centers) or the public domain (internet data centers, co-location data centers, and other service provider data centers). Enterprise facilities include private corporations, institutions or government agencies, and may involve the establishment of either intranets or extranets. Internet facilities include traditional telephone service providers, unregulated competitive service providers and related commercial operators. The topologies specified in this document, however, are intended to be applicable to both in satisfying their respective requirements for connectivity (internet access and wide-area communications), operational hosting (web hosting, file storage and backup, database management, etc.), and additional services (application hosting, content distribution, etc.). Failsafe power, environmental controls, fire suppression, system redundancy and security are also common requirements to facilities that serve both the private and public domain.

Stewardship --`,,```,,,,````-`-`,,`,,`,`,,`---

Telecommunications infrastructure affects raw material consumption. The infrastructure design and installation methods also influence product life and sustainability of electronic equipment life cycling. These aspects of telecommunications infrastructure impact our environment. Since building life cycles are typically planned for decades, technological electronic equipment upgrades are necessary. The telecommunications infrastructure design and installation process magnifies the need for sustainable infrastructures with respect to building life, electronic equipment life cycling and considerations of effects on environmental waste. Telecommunications

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ANSI/TIA-PN-942-B designers are encouraged to research local building practices for a sustainable environment and conservation of fossil fuels as part of the design process. See ANSI/TIA-4994 and TIA TSB-5046 for sustainability processes and guidelines.

Specification of criteria Two categories of criteria are specified; mandatory and advisory. The mandatory requirements are designated by the word "shall"; advisory requirements are designated by the words "should”, "may", or "desirable" which are used interchangeably in this Standard. Mandatory criteria generally apply to protection, performance, istration and compatibility; they specify minimally acceptable requirements. Advisory criteria are presented when their attainment may enhance the general performance of the cabling system in all its contemplated applications. A note in the text, table, or figure is used for emphasis or offering informative suggestions, or providing additional information.

Metric equivalents of US customary units The dimensions in this Standard are metric or US customary with approximate conversion to the other.

Life of this Standard This Standard is a living document. The criteria contained in this Standard are subject to revisions and updating as warranted by advances in building construction techniques and telecommunications technology.

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ANSI/TIA-PN-942-B

1 SCOPE This Standard specifies the minimum requirements for telecommunications infrastructure of data centers and computer rooms, including single tenant enterprise data centers and multi-tenant data centers. The topology specified in this document is intended to be applicable to any size data center.

2 NORMATIVE REFERENCES The following standard contains provisions that, through references in this text, constitute provisions of this Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this Standard are encouraged to investigate the possibility of applying the most recent editions of the standards published by them. a) ANSI/ATIS 0600404:2005, Network and Customer Installation Interfaces – DS3 and Metallic Interface Specification b) ANSI/NFPA 75-2017, Standard for the Fire Protection of Information Technology Equipment® c) ANSI/TIA-568.0‐D:2015 – Generic Telecommunications Cabling for Customer Premises d) ANSI/TIA-568.1‐D:2015 – Commercial Building Telecommunications Infrastructure Standard e) ANSI/TIA-568-C.2:2009, Components Standard f)

Balanced

Twisted-Pair

Telecommunications

Cabling

and

ANSI/TIA-568.3‐D:2016 – Optical Fiber Cabling and Components Standard

g) ANSI/TIA-568.4‐D:2017 – Broadband Coaxial Cable and Components Standard h) ANSI/TIA-569-D:2015 – Telecommunications Pathways and Spaces i)

ANSI/TIA-604-5-E:2015 – FOCIS 5 – Fiber Optic Connector Intermateability Standard, Type MPO

j)

ANSI/TIA-604-10-B:2008 – FOCIS 10 – Fiber Optic Connector Intermateability Standard, Type LC

k) ANSI/TIA-604-18:2015 – FOCIS 18 – Fiber Optic Connector Intermateability Standard, Type MPO-16 l)

ANSI/TIA-606-C:2017 – istration Standard for Telecommunications Infrastructure

m) ANSI/TIA-607-C:2015 – Telecommunications Bonding and Grounding (Earthing) for Customer Premises n) ANSI/TIA-758-B:2012 – Customer-Owned Outside Plant Telecommunications Infrastructure Standard o) ANSI/TIA-862-B:2016 – Structured Cabling Infrastructure Standard for Intelligent Building Systems p) ANSI/TIA-5017:2016 – Telecommunications Physical Network Security Standard q) ANSI/TIA-5048:2017 – Automated infrastructure Requirements, data exchange and applications r)

management

(AIM)

OSHA CFR 1926.441 – Battery Rooms and Battery Charging

s) Telcordia GR-63:2012 – NEBSTM Requirements: Physical Protection t)

Telcordia GR-3175:2014 – Generic Requirements for Intrabuilding Coaxial Cable

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systems

–