1、BRITISH STANDARD BS ISO/IEC 14709-1:1997 Information technology Configuration of Customer Premises Cabling (CPC) for applications Part 1: ISDN basic access ICS 33.080BSISO/IEC14709-1:1997 This British Standard, having been prepared under the directionof the DISC Board, waspublished under the authori
2、tyof the Standards Boardand comes into effect on 15 November 1997 BSI 04-2000 ISBN 0 580 27863 8 National foreword This British Standard reproduces verbatim ISO/IEC 14709-1:1997 and implements it as the UK national standard. The UK participation in its preparation was entrusted to Technical Committe
3、e IST/39, Interconnection of IT Equipment, Cabling, Microprocessors, which has the responsibility to: aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; mo
4、nitor related international and European developments and promulgate them in the UK. A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this do
5、cument may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of
6、 British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, theISO/IEC title page, pages ii to iv, pages
7、1 to 16 and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover. Amendments issued since publication Amd. No. Date CommentsBSISO/IEC14709-1:1997 BSI 04-2000 i Contents Page
8、 National foreword Inside front cover Foreword iv Text of ISO/IEC 14709-1 1ii blankBSISO/IEC14709-1:1997 ii BSI 04-2000 Contents Page Foreword iv Introduction 1 1 Scope 1 2 Normative references 1 3 Definitions 1 4 Abbreviations and symbols 2 4.1 Abbreviations 2 4.2 Symbols 2 5 Design requirements 3
9、5.1 General 3 5.2 Insertion loss 3 5.3 Longitudinal conversion loss 3 5.4 Round trip delay 3 5.5 Power feeding 3 5.6 Electromagnetic environment 4 5.7 Spurs 4 5.8 Near-end crosstalk loss (NEXT) 4 6 Configurations 4 6.1 General 4 6.2 The point-to-point configuration 5 6.3 The short passive bus config
10、uration 6 6.4 The extended passive bus configuration 7 6.5 The Y-configuration 7 6.6 The star configuration 8 6.7 Implementation over structured cabling systems 8 7 Minimum requirements for cabling components 11 7.1 General 11 7.2 Cables 11 7.3 Terminal cords 11 7.4 Terminating resistors 12 7.5 Outl
11、ets and joint boxes 12 7.6 Cross-connect products/patch cords 12 8 Cabling qualification 12 8.1 General 12 8.2 Spurs 13 8.3 Cabling integrity 13 8.4 D.c. loop resistance 13 8.5 D.c. lead resistance unbalance 13 8.6 Insulation resistance 13 8.7 Insertion loss 13 8.8 Round trip delay 14 8.9 Characteri
12、stic impedance 14 8.10 Near end crosstalk (NEXT) loss 14 8.11 Impulsive noise 14 8.12 Bit error rates 14 8.13 Longitudinal conversion loss 14 Annex A (informative) Bibliography 15 Annex B (informative) Examples of maximum distances for specific common cables 16 Figure 1 Round trip delay requirements
13、 4BSISO/IEC14709-1:1997 BSI 04-2000 iii Page Figure 2 Point-to-point configuration 5 Figure 3 Short passive bus 6 Figure 4 Extended passive bus 7 Figure 5 Y-configuration 8 Figure 6 NT location in the generic cabling structure 9 Figure 7 ISDN structured cabling adapter 10 Figure 8 ISDN structured ca
14、bling multipoint adapter 10 Figure 9 ISDN structured cabling multipoint adapters in series 11 Table 1 Maximum insertion loss for each configuration 3 Table 2 Pin assignments 12 Table B.1 Examples of recommended maximum distances fortypicalinstallations 16 Descriptors: Data processing, information in
15、terchange, telecommunications, ISDN, public network, buildings, premises, communication cables, cabling, specifications.BSISO/IEC14709-1:1997 iv BSI 04-2000 Foreword ISO (the International Organization for Standardization) and IEC (the International Electrotechnical Commission) form the specialized
16、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 committee
17、s 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. Draft Internatio
18、nal Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as an International Standard requires approval by at least 75 % of the national bodies casting a vote. International Standard ISO/IEC 14709-1 was prepared by Joint Technical Committee ISO
19、/IEC JTC 1, Information technology, Subcommittee SC 25, Interconnection of information technology equipment. ISO/IEC 14709 consists of the following parts, under the general title Information technology Configuration of Customer Premises Cabling (CPC) for applications: Part 1: Integrated Services Di
20、gital Network (ISDN) basic access; Part 2: Integrated Services Digital Network (ISDN) primary access; Annex A and Annex B of this part of ISO/IEC 14709 are for information only.BSISO/IEC14709-1:1997 BSI 04-2000 1 Introduction This part of ISO/IEC 14709 is intended for use by those designing, plannin
21、g or procuring cabling for ISDN basic access within a customers premises. The configurations in this part of ISO/IEC 14709 are designed to be effective when either implemented with cabling having the recommended characteristics, or implemented with the components specified in clause 7. In addition,
22、guidance is given for the use of generic cabling in accordance with ISO/IEC 11801. 1 Scope This part of ISO/IEC 14709 defines the requirements for the design and configuration of customer premises cabling for the connection of basic access ISDN equipment. It defines design requirements for ISDN basi
23、c access with point-to-point and point-to-multipoint cabling configurations; minimum cabling requirements for the installation of new cabling 1) ; criteria for the use of generic cabling; criteria for the use of existing cabling. This part of ISO/IEC 14709 applies to the customer premises cabling. I
24、t describes the cabling requirements, needed to transmit ISDN basic access signals as defined by ITU-T Recommendation I.430. The requirements placed on the customer premises cabling are solely those necessary to enable terminal equipment conforming to ITU-T Rec. I.430 to operate into the Network Ter
25、mination (NT) via configurations defined in this part of ISO/IEC 14709. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this part of ISO/IEC 14709. At the time of publication, the editions indicated were valid. All sta
26、ndards are subject to revision, and parties to agreements based on this part of ISO/IEC 14709 are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO
27、/IEC 8877:1992, Information technology Telecommunications and information exchange between systems Interface connector and contact assignments for ISDN Basic Access Interface located at reference points S and T. ISO/IEC 11801:1995, Information technology Generic cabling for customer premises. IEC 60
28、3-7:1996, Connectors for frequencies below3MHz for use with printed boards Part7:Detail specification for connectors, 8-way, including fixed and free connectors with common mating features, with assessed quality. ITU-T Rec I.430 (Blue Book), ISDN user-network interface; Layer 1 recommendations. 3 De
29、finitions The meaning of the term round trip delay can be found in ITU-T Recommendation I.430 (BlueBook),A.2. Furthermore, for the purposes of this part of ISO/IEC 14709, the following definitions apply. 3.1 cabling the assembly of all cables, connections, patch panels and other passive components w
30、hich comprise the telecommunications infrastructure 3.2 network termination the functional group on the network side of a user-network interface NOTEA network termination always comprises a transmission part NT1 and optionally a switching part NT2. 1) Although this part of ISO/IEC 14709 specifies th
31、e minimum requirements for cabling dedicated to ISDN basic access, it is highly recommended that cabling newly installed complies with ISO/IEC 11801 class B or higher.BSISO/IEC14709-1:1997 2 BSI 04-2000 3.3 power feeding the function which provides for the capability to transfer power across the int
32、erface of the NT 3.4 terminal equipment the functional group on the user side of a user-network interface NOTETerminal equipment includes terminal(s), terminal adapter(s) and, if any, NT2 functional group. 4 Abbreviations and symbols 4.1 Abbreviations NOTEThe meanings of the abbreviations S, S 0and
33、T conform to ITU-T Recommendation I.430. 4.2 Symbols BD Building distributor CD Campus distributor FD Floor distributor FFS For further study ISDN Integrated services digital network NEXT Near-end crosstalk loss NT1 Network termination 1 NT2 Network termination 2 S S reference point S 0 S 0interface
34、 SC Structured cabling T T reference point TE Terminal equipment TP Transition Point TR Terminating resistor cable spur/tap with a junction to a cable which is the terminated bus Network Termination Terminating Resistors outlet according to IEC 603-7 plug according to IEC 603-7BSISO/IEC14709-1:1997
35、BSI 04-2000 3 5 Design requirements 5.1 General Signals passing between the NT and TE(s) for the various configurations are subject to attenuation, delay and distortion. Cabling components (including extension cords, adapters, cross-connect components, outlets, junction boxes, cables, spurs etc.) an
36、d connected terminals all contribute to these effects. The design requirements for the cabling are dependent on the configuration chosen. 5.2 Insertion loss The insertion loss is measured from the NT to the TR at 96 kHz with 100 7 source and load impedances. The maximum insertion loss for each confi
37、guration is shown in Table 1. Table 1 Maximum insertion loss for eachconfiguration 5.3 Longitudinal conversion loss The longitudinal conversion loss of the cabling shall be equal to, or greater than, 43 dB when measured at96 kHz. 5.4 Round trip delay The round trip delay introduced by the cabling sh
38、all not exceed: a) 2,0 4s for the total cabling of both the short passive bus at 96 kHz and the Y-configuration; b) 0,5 4s differential round trip delay for the cabling between the first and last outlet of the extended passive bus. These requirements are illustrated in Figure 1. 5.5 Power feeding Th
39、e length of the cabling may be limited by the cable resistivity, the number of terminals, their power consumption and the capability of the remote power sources. The loop resistance has to be controlled in order to fulfil the power feeding requirements and to avoid static saturation of inductive com
40、ponents in NT and TEs due to the difference in d.c. resistances of the two wires making up the twisted pair. The d.c. resistance unbalance of the two wires shall not exceed 3 % if the loop resistance is greater than 5 7. In the majority of cases power is supplied via the phantom of the transmit and
41、receive pairs. In this case only two pairs are used. In some applications a third pair is needed for power source 2 and powersink 2. any socket any plug joint of outlet Configuration Insertion loss at 96 kHz Point-to-point 6 dB Extended passive bus 4 dB Short passive bus not critical Y-configuration
42、 not criticalBSISO/IEC14709-1:1997 4 BSI 04-2000 5.6 Electromagnetic environment The ISDN basic access is designed to work in most environments. However, its performance may be degraded by interference from external electromagnetic sources (such as motors) and interference from other transmission sy
43、stems sharing the same cable. The impulsive noise generated by, for instance, analogue telephony or unbalanced data interfaces, can cause interference with signals carried on the ISDN cabling. Crosstalk can be limited by using pairs for ISDN basic rate in separate cables or in separate bundles of pa
44、irs in the same cable. Before sharing of ISDN S-bus with other transmission systems in the same cable it shall be verified that they do not interfere with each other. In noisy environments or adjacent to sensitive equipment, shielded cabling may be advisable. Cables routed outside of buildings may r
45、equire protection devices. The attenuation and capacitance of protection devices shall be taken into account. 5.7 Spurs Because spurs will add capacitance to the cabling, they are not recommended. When needed, the length of spurs used for connection of terminal outlets shall not exceed 1 m. The leng
46、th of a spur used to attach a NT should not exceed 0,5 m. 5.8 Near-end crosstalk loss (NEXT) The near-end crosstalk loss of the cabling shall be greater than 35 dB at 96 kHz. It is recommended that the NEXT of the cable be greater than 54 dB for satisfactory noise immunity (see 7.2). 6 Configuration
47、s 6.1 General The following design requirements are common to all ISDN basic access user network interface configurations: a) Where S 0interfaces can be extended under fallback mode (e.g. when the NT2 is bypassed), further loss and delay will be introduced into the link. The design requirements appl
48、y to worst case conditions. Figure 1 Round trip delay requirementsBSISO/IEC14709-1:1997 BSI 04-2000 5 b) The TE may be hardwired to the cable termination. If a TE cord is used it shall comply with ISO/IEC 8877. c) terminating resistors see 7.4) are needed at both ends of the transmit and receive pai
49、rs. Locations are shown in Figure 2 to Figure 5 and Figure 7 to Figure 9. 2)If a specific configuration requires the terminating resistors at the NT, these terminating resistors shall always be present either within the NT or at the connection point between the NT (cord) and the bus cabling. d) The NT may be connected to the cabling in three ways: hardwired; with a outlet integral to the NT; via a flexible cord with a plug. ISO/IEC 8877 and IEC 603-7 may be applied for the case with a connector at the NT. If
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