ISO/IEC TR 11801-9907:2019

Information technology - Generic cabling for customer premises - Part 9907: Specifications for direct attach cabling

ISO/IEC TR 11801-9907:2019(E), which is a Technical Report, provides definitions for, and examples of, direct attach cabling configurations. This document provides performance specifications for Classes D, E, EA, F, FA, I and II direct attach cabling by reference to ISO/IEC 11801-1. Informative limits for Class I direct attach cabling to support 5 m short reach mode application according to ISO/IEC/IEEE 8802 3:2017/AMD3, i.e. 25GBASE-T and 40GBASE-T, are provided in Annex A. Test methods will be provided in the second edition of ISO/IEC 14763-4. Direct attach cabling connects two pieces of equipment, it has connectors at each end, and no intermediate connecting hardware.

General Information

• Status: Published
• Publication Date: 15-Jul-2019
• ICS: 35.200 - Interface and interconnection equipment
• Technical Committee: ISO/IEC JTC 1/SC 25 - Interconnection of information technology equipment
• Current Stage: PPUB - Publication issued
• Start Date: 16-Jul-2019
• Completion Date: 21-Aug-2019

Overview

ISO/IEC TR 11801-9907:2019 is a Technical Report that defines and specifies direct attach cabling for customer premises as part of the ISO/IEC 11801 generic cabling family. It describes direct-attach configurations (cables with connectors at both ends and no intermediate connecting hardware) and provides performance specifications for Classes D, E, EA, F, FA, I and II by reference to ISO/IEC 11801-1. The report is informative and intended to help designers, manufacturers and installers verify direct-attach assemblies and their ability to support modern link applications.

Key Topics

• Definitions and configurations for direct attach cabling (connectorized cable assemblies connecting two pieces of equipment).
• Performance specifications (Clause 6) referenced to ISO/IEC 11801-1, including parameters such as:
  • Return loss and insertion loss
  • NEXT / PS NEXT and ACR-N / PS ACR-N
  • ACR-F / PS ACR-F, TCL, ELTCTL
  • Coupling attenuation and alien crosstalk
  • DC loop resistance and pair resistance unbalance
  • Propagation delay and delay skew
• Testing regimes for reference and installation performance (reference to test regimes and Table 1) and guidance on installation performance verification.
• Annex A (informative): provides short-reach Class I limits to support 5 m short-reach mode applications (per ISO/IEC/IEEE 8802-3:2017/AMD3) such as 25GBASE-T and 40GBASE-T.
• Note: Formal test methods for direct attach cabling will be published in the second edition of ISO/IEC 14763-4.

Applications and Who Uses It

• Network and data center designers selecting or specifying direct-attach copper assemblies.
• Cable and connector manufacturers developing connectorized cable assemblies to meet Class D–II performance.
• Installation contractors and cabling testers responsible for performance verification and acceptance testing.
• Standards writers and procurement teams specifying cabling for short-reach, high-speed Ethernet (including 25G/40GBASE-T) or equipment-to-equipment links.
• Useful where equipment is linked directly without patch panels or intermediate connectivity (e.g., server-to-switch short connections).

Related Standards

• ISO/IEC 11801-1 - General requirements for generic cabling (normative reference).
• ISO/IEC 14763-4 - Test methods for end-to-end links (second edition will include direct attach methods).
• ISO/IEC/IEEE 8802-3:2017/AMD3 - Ethernet amendment referenced for 5 m short-reach mode (25G/40GBASE-T).
• ISO/IEC TR 11801-9903 - Modelling techniques referenced for performance derivation.

This Technical Report is essential reading when specifying or validating connectorized, equipment-to-equipment cabling where consistent Class-based performance and short-reach high-speed support are required.

Standards Content (Sample)

ISO/IEC TR 11801-9907
Edition 1.0 2019-07
TECHNICAL
REPORT
Information technology – Generic cabling for customer premises –
Part 9907: Specifications for direct attach cabling

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ISO/IEC TR 11801-9907
Edition 1.0 2019-07
TECHNICAL
REPORT
Information technology – Generic cabling for customer premises –

Part 9907: Specifications for direct attach cabling

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 35.200 ISBN 978-2-8322-7195-7

– 2 – ISO/IEC TR 11801-9907 © ISO/IEC 2019
CONTENTS
FOREWORD . 4
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms, definitions, abbreviated terms and symbols . 6
3.1 Terms and definitions . 6
3.2 Abbreviated terms . 7
3.3 Symbols . 7
4 Specifications . 7
5 Direct attach cabling configuration . 7
6 Performance specifications . 8
6.1 General . 8
6.2 Return loss limits . 8
6.3 Insertion loss limits . 8
6.4 NEXT limits . 8
6.5 PS NEXT limits . 8
6.6 ACR-N limits . 8
6.7 PS ACR-N limits . 8
6.8 ACR-F limits . 8
6.9 PS ACR-F limits . 8
6.10 TCL limits . 8
6.11 ELTCTL limits . 8
6.12 Coupling attenuation . 9
6.13 Alien crosstalk . 9
6.14 Direct current loop resistance . 9
6.15 Direct current resistance unbalance within a pair . 9
6.16 Propagation delay . 9
6.17 Delay skew . 9
7 Direct attach cabling performance . 9
7.1 General . 9
7.2 Reference performance testing . 9
7.3 Installation performance testing . 10
7.4 Installation performance testing of direct attach cabling . 10
8 Testing of direct attach cabling . 12
Annex A (informative) Short reach Class I direct attach channel transmission
performance . 13
A.1 General . 13
A.2 Short reach Class I direct attach cabling return loss . 13
A.3 Short reach Class I direct attach cabling insertion loss . 13
A.4 Short reach Class I direct attach cabling NEXT . 13
A.5 Short reach Class I direct attach cabling PS NEXT . 14
A.6 Short reach Class I direct attach cabling ACR-F . 14
A.7 Short reach Class I direct attach cabling PS ACR-F . 15
A.8 Short reach Class I direct attach cabling propagation delay . 15
A.9 Short reach Class I direct attach cabling delay skew . 15

ISO/IEC TR 11801-9907 © ISO/IEC 2019 – 3 –
A.10 Short reach Class I direct attach cabling PS ANEXT . 15
A.11 Short reach Class I direct attach cabling PS AACR-F . 16
Bibliography . 17

Figure 1 – Direct attach cabling . 7

Table 1 – Test regime for reference performance and installation performance – Direct
attach cabling of Classes D, E, E , F, F , I, II . 11
A A
Table A.1 – Short reach Class I direct attach cabling return loss . 13
Table A.2 – Short reach Class I direct attach cabling insertion loss . 13
Table A.3 – Short reach Class I direct attach cabling NEXT . 14
Table A.4 – Short reach Class I direct attach cabling PS NEXT . 14
Table A.5 – Short reach Class I direct attach cabling ACR-F . 14
Table A.6 – Short reach Class I direct attach cabling PS ACR-F . 15
Table A.7 – Short reach Class I direct attach cabling propagation delay . 15
Table A.8 – Short reach Class I direct attach cabling PS NEXT . 16
Table A.9 – Short reach Class I direct attach cabling PS AACR-F . 16

– 4 – ISO/IEC TR 11801-9907 © ISO/IEC 2019
INFORMATION TECHNOLOGY –
GENERIC CABLING FOR CUSTOMER PREMISES –

Part 9907: Specifications for direct attach cabling

FOREWORD
1) 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
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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.
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The main task of IEC and ISO technical committees is to prepare International Standards.
However, a technical committee may propose the publication of a Technical Report when it
has collected data of a different kind from that which is normally published as an International
Standard, for example "state of the art".
ISO/IEC TR 11801-9907, which is a Technical Report, was prepared by subcommittee 25:
Interconnection of information technology equipment, of ISO/IEC joint technical committee 1:
Information technology.
The list of all currently available parts of the ISO/IEC 11801 series, under the general title
Information technology – Generic cabling for customer premises, can be found on the IEC
website.
The text of this Technical Report is based on the following documents:
DTR Report on voting
JTC1-SC25/2841/DTR JTC1-SC25/2863/RVDTR
Full information on the voting for the approval of this Technical Report can be found in the
report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A bilingual version of this document may be issued at a later date.

ISO/IEC TR 11801-9907 © ISO/IEC 2019 – 5 –
INTRODUCTION
This document provides definitions and examples of direct attach cabling. It provides
performance specifications for Classes D, E, E , F, F , I and II direct attach cabling that can
A A
also be used to verify terminating connectors. Performance verification for direct attach
cabling will be specified in the second edition of ISO/IEC 14763-4.

– 6 – ISO/IEC TR 11801-9907 © ISO/IEC 2019
INFORMATION TECHNOLOGY –
GENERIC CABLING FOR CUSTOMER PREMISES –

Part 9907: Specifications for direct attach cabling

1 Scope
This part of ISO/IEC 11801, which is a Technical Report, provides definitions for, and
examples of, direct attach cabling configurations.
This document provides performance specifications for Classes D, E, E , F, F , I and II direct
A A
attach cabling by reference to ISO/IEC 11801-1.
Informative limits for Class I direct attach cabling to support 5 m short reach mode application
according to ISO/IEC/IEEE 8802-3:2017/AMD3, i.e. 25GBASE-T and 40GBASE-T, are
provided in Annex A.
Test methods will be provided in the second edition of ISO/IEC 14763-4.
NOTE ISO/IEC 14763-4 is the test method for End to End (E2E) link. It can be also used for direct attach cabling.
Test methods for Classes E , F, F , I, II will be provided in the second edition of ISO/IEC 14763-4.
A A
Direct attach cabling connects two pieces of equipment, it has connectors at each end, and no
intermediate connecting hardware.
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
...