ISO/IEC TECHNICAL REPORT TR 24750 First edition 2007-07 Information technology - Assessment and mitigation of installed balanced cabling channels in order to support 10GBASE-T IEC ISO Reference number ISO/IEC TR 24750:2007(E) THIS PUBLICATION IS COPYRIGHT PROTECTED Copyright @ 2007 ISO/lEC, Geneva, Switzerland or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either IEC or IEC's member National Committee in the country of the requester. If you have any questions about Iso/lEc copyright or have an enquiry about obtaining additional rights to this IEC Central Office 3, rue de Varembé CH-1211 Geneva 20 Switzerland Email: [email protected] Web: www.iec.ch About the IEC The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes International Standards for all electrical, electronic and related technologies. AboutIECpublications The technical content of IEC publications is kept under constant review by the IEC.Please make sure that you have the latest edition,a corrigenda oranamendment might have beenpublished. . Catalogue of IEC publications: www.iec.ch/searchpub The IEc on-line Catalogue enables you to search by a variety of criteria (reference number, text, technical committee,...). It also gives information on projects, withdrawn and replaced publications. • IEC Just Published: www.iec.ch/online news/justpub Stay up to date on all new IEC publications.Just Published details twice a month all new publications released.Available on-line and also by email. Customer Service Centre: www.iec.ch/webstorelcustserv If you wish to give us your feedback on this publication or need further assistance, please visit the Customer Service Centre FAQ or contact us: Email: [email protected] Tel.: +41 22 919 02 11 Fax: +41 22 919 03 00 ISO/EC TECHNICAL REPORT - TYPE 2 TR 24750 First edition 2007-07 Information technology - Assessment and mitigation of installed balanced cabling channels in order to support 10GBASE-T PRICECODE M IEC ISO For price, see current catalogue TR 24750 @ ISO/IEC:2007(E) -2 - CONTENTS FOREWORD.. INTRODUCTION. 1 Scope. 2 Normative references. 3 Terms, definitions and abbreviations.. 3.1 Terms and definitions . 3.2 Abbreviations.... 9 4 New parameters needed for generic cabling for the support of 10GBASE-T 5 Channel requirements .. 5.1 General 5.2 Return loss... 12 5.3 Insertion loss ... 5.4 Near-end crosstalk loss (NEXT).. 13 5.4.1 Pair-to-pair NEXT 13 5.4.2 Power sum NEXT (PS NEXT).. 13 5.5 Attenuation to crosstalk loss ratio near-end (ACR-N)... 14 5.5.1 Pair-to-pair ACR-N.. 14 5.5.2 Power sum ACR-N (PS ACR-N) .. 5.6 Attenuation to crosstalk loss ratio far-end (ACR-F). 15 5.6.1 Pair-to-pair ACR-F 5.6.2 Power sum ACR-F (PS ACR-F) 16 5.7 Alien crosstalk. 5.7.1 General.. 5.7.2 Power sum alien NEXT (PS ANEXT) 5.7.3 Power sum attenuation to alien crosstalk ratio far-end (PS AACR-F) 5.7.4 Alien crosstalk margin computation ... .21 5.7.5 Examples of implementations at key insertion loss at 250 MHz.. ..21 5.8 Propagation delay... .21 5.9 Delay skew... 6 Guidance for mitigation .... .22 6.1 Certification, measurement and documentation. .22 6.2 Mitigation techniques if in-channel parameters of the channel from clause 5 are not met... 22 6.3 Mitigation techniques in case external parameters of the channel (alien noise) from 5.7 are not met... 23 6.3.1 General .. 6.3.2 Screened cabling .. .23 6.3.3 Unscreened cabling .. ...23 6.3.4 Grouped connectors .24 6.3.5 Example of a step by step mitigation procedure... .24 Annex A (informative) Permanent link performance guidelines .. .26 A.1 General. A.2 Return loss. .26 A.3Insertionloss 26 A.4 NEXT 26 TR 24750 @ ISO/IEC:2007(E) -3- A.4.1 Pair-to-pair NEXT. .26 A.4.2 Power sum NEXT (PS NEXT) .27 A.5 ACR-F.. .27 A.5.1 Pair-to-pair ACR-F.. A.5.2 Power sum ACR-F (PS ACR-F).. ...27 Annex B (normative) Alien crosstalk margin computation ..28 B.1 General .... B.2 Terms, definitions and abb