1、National Standard of CanadaCAN/CSA-ISO/IEC 8481-01(ISO/IEC 8481:1996)International Standard ISO/IEC 8481:1996 (second edition, 1996-06-15), has been adopted withoutmodification as CSA Standard CAN/CSA-ISO/IEC 8481-01, which has been approved as a NationalStandard of Canada by the Standards Council o
2、f Canada.ISBN 1-55324-412-5 March 2001Reference numberISO/IEC 8481:I996(E)The Canadian Standards Association, which The Standards Council of Canada is theoperates under the name CSA International coordinating body of the National Standards system, (CSA), under whose auspices this National Standard h
3、as a federation of independent, autonomousbeen produced, was chartered in 1919 and accredited by organizations working towards the furtherthe Standards Council of Canada to the National development and improvement of voluntaryStandards system in 1973. It is a not-for-profit, standardization in the n
4、ational interest.nonstatutory, voluntary membership association The principal objects of the Council are to foster engaged in standards development and certification and promote voluntary standardization as a means activities. of advancing the national economy, benefiting theCSA standards reflect a
5、national consensus of producers health, safety, and welfare of the public, assisting and users including manufacturers, consumers, and protecting the consumer, facilitating domestic retailers, unions and professional organizations, and and international trade, and furthering internationalgovernmenta
6、l agencies. The standards are used widely cooperation in the field of standards.by industry and commerce and often adopted by A National Standard of Canada is a standard whichmunicipal, provincial, and federal governments in their has been approved by the Standards Council ofregulations, particularl
7、y in the fields of health, safety, Canada and one which reflects a reasonablebuilding and construction, and the environment. agreement among the views of a number of capableIndividuals, companies, and associations across Canada individuals whose collective interests provide to theindicate their supp
8、ort for CSAs standards development greatest practicable extent a balance ofby volunteering their time and skills to CSA Committee representation of producers, users, consumers, andwork and supporting the Associations objectives others with relevant interests, as may be appropriatethrough sustaining
9、memberships. The more than 7000 to the subject in hand. It normally is a standardcommittee volunteers and the 2000 sustaining which is capable of making a significant and timelymemberships together form CSAs total membership contribution to the national interest.from which its Directors are chosen.
10、Sustaining Approval of a standard as a National Standard ofmemberships represent a major source of income for Canada indicates that a standard conforms to theCSAs standards development activities. criteria and procedures established by the StandardsThe Association offers certification and testing se
11、rvices Council of Canada. Approval does not refer to thein support of and as an extension to its standards technical content of the standard; this remains thedevelopment activities. To ensure the integrity of its continuing responsibility of the accreditedcertification process, the Association regul
12、arly and standards-development organization.continually audits and inspects products that bear the Those who have a need to apply standards areCSA Mark. encouraged to use National Standards of CanadaIn addition to its head office and laboratory complex in whenever practicable. These standards are su
13、bject Toronto, CSA has regional branch offices in major centres to periodic review; therefore, users are cautioned across Canada and inspection and testing agencies in to obtain the latest edition from the organizationeight countries. Since 1919, the Association has preparing the standard.developed
14、the necessary expertise to meet its corporate The responsibility for approving National Standards mission: CSA is an independent service organization of Canada rests with thewhose mission is to provide an open and effective forum Standards Council of Canadafor activities facilitating the exchange of
15、 goods and 270 Albert Street, Suite 200services through the use of standards, certification and Ottawa, Ontario, K1P 6N7related services to meet national and international needs. CanadaFor further information on CSA services, write toCSA International178 Rexdale BoulevardToronto, Ontario, M9W 1R3Can
16、adaAlthough the intended primary application of this Standard is stated in its Scope, it is importantto note that it remains the responsibility of the users to judge its suitability for their particular purpose.Registered trade-mark of Canadian Standards AssociationInformation technology Telecommuni
17、cations and informationCAN/CSA-ISO/IEC 8481-01 exchange between systems DTE to DTE direct connectionsMarch 2001 CSA/1CAN/CSA-ISO/IEC 8481-01Information technology Telecommunications andinformation exchange betweensystems DTE to DTE directconnectionsCSA PrefaceStandards development within the Informa
18、tion Technology sector is harmonized with internationalstandards development. Through the CSA Technical Committee on Information Technology (TCIT),Canadians serve as the Canadian Advisory Committee (CAC) on ISO/IEC Joint Technical Committee 1 onInformation Technology (ISO/IEC JTC1) for the Standards
19、 Council of Canada (SCC), the ISO memberbody for Canada and sponsor of the Canadian National Committee of the IEC. Also, as a member of theInternational Telecommunication Union (ITU), Canada participates in the International Telegraph andTelephone Consultative Committee (ITU-T).This International St
20、andard was reviewed by the CSA TCIT under the jurisdiction of the StrategicSteering Committee on Information Technology and deemed acceptable for use in Canada. (Acommittee membership list is available on request from the CSA Project Manager.) From time to time,ISO/IEC may publish addenda, corrigend
21、a, etc. The CSA TCIT will review these documents for approvaland publication. For a listing, refer to the CSA Information Products catalogue or CSA Info Update orcontact a CSA Sales representative. This Standard has been formally approved, without modification, bythese Committees and has been approv
22、ed as a National Standard of Canada by the Standards Council ofCanada.March 2001 CSA International 2001All rights reserved. No part of this publication may be reproduced in any form whatsoever without the prior permission ofthe publisher. ISO/IEC material is reprinted with permission. Inquiries rega
23、rding this National Standard of Canada shouldbe addressed to CSA International, 178 Rexdale Boulevard, Toronto, Ontario, M9W 1R3.INTERNATIONAL STANDARD ISO/IEC 8481 Second edition 1996-06-15 Information technology - Telecommunications and information exchange between systems - DTE to DTE direct conn
24、ections Technologies de /information - TMcommunica tions et change d informa tion en tre sys tkmes - Connexions directes de DTE 2 DTE Reference number ISO/lEC 8481 :I 996(E) ISO/IEC $481:19964E) Foreword IS0 (the International Organization for Standardization) and IEC (the Inter- national Electrotec
25、hnical Commission) form the specialized system for worldwide standardization. National bodies that are members of IS0 or IEC participate in the development of International Standards through technical committees established by the respective organization to deal with particu- lar fields of technical
26、 activity. IS0 and IEC technical committees collab- orate in fields of mutual interest. Other international organizations, governmental and non-governmental, in liaison with IS0 and IEC, also take part in the work. In the field of information technology, IS0 and IEC have established a joint technica
27、l committee, lSO/IEC JTC 1. Draft International 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 lSO/IEC 8481 was
28、prepared by Joint Technical Committee lSO/l EC JTC 1, Information technology, Telecommunications and information exchange between systems. This second edition cancels and replaces the first edition (IS0 8481:1986), which has been technically revised. Annex A of this International Standard is for inf
29、ormation only. 0 ISO/lEC 1996 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher. ISO/I EC Copyright O
30、ffice l Case postale 56 l CH-1211 Geneve 20 l Switzerland Printed in Switzerland 0 ISO/IEC Introduction This International Standard provides for the interconnection of Data Terminal Equipment (DTE) without attached to a Data Circuit-terminating Equipment (DCE), this being part of a telecommunication
31、 facility. The desired DTE to DTE direct connection may be totally located at the users premises. The aim is the ITU-T and ISO/IEC standardised DTWDCE interfaces, in order to avoid equipment proliferation. to lSO/lEC 8481 :I 996(E) signal conversion, whereby a DTE is not these interconnections to th
32、e elements of The normative part of this standard provides for interconnection for both asynchronous and synchronous transmission, using CCITT Recommendation X.24 interchange circuits, including circuit X for synchronous transmission, and using ITU-T Recommendation V.ll electrical characteristics. A
33、n informative annex provides guidance for other cases of interconnection that, though acceptable under limited conditions, cannot be recommended for general use. These alternatives include timing arrangements for synchronous transmission, not reliant on circuit X being provided in both DTEs with ITU
34、-T Recommendation V.11 electrical characteristics. The informative annex does not cover direct connection between ISDN terminal equipments transmitted signal is such that no general method of interconnection can be recommended. (type TEl) for which the complexity in the framing of the . . . III This
35、 page intentionally left blank INTERNATIONAL STANDARD 0 ISO/IEC lSO/IEC 8481:1996(E) Information technology - Telecommunications and information exchange between systems.- DTE to DTE direct connections 1 Scope 3 Interconnection configuration This International Standard describes an arrangement for i
36、nterconnection of Data Terminal Equipment (DTE), without intermediate Data Circuit-terminating Equipment (DCE), in terms of electrical, mechanical, and functional characteristics. This International Standard applies to DTEs with interface circuits standardised in CCITT Recommendation X.24 for transm
37、ission over public data networks. The interconnections are restricted to point-to- point connections. NOTE - The extension to multipoint configurations is at present under study and would use electrical charqcteristics according to ISO/lEC 8482 - Information Technology - Telecommunications and Infor
38、mation Exchange between Systems - Twisted pair Multipoint interconnection. This International Standard applies to DTEs which employ the balanced electrical characteristics of ITU-T V.ll for data signalling rates up to IO Mbit/s. The interconnection may be used for start-stop or synchronous transmiss
39、ion. For synchronous transmission, this International Standard applies to DTEs which use circuit X - DTE transmit element timing - and circuit S - Signal element timing - (see clause 5). An informative annex provides information for the interconnection of DTEs with interface circuits according to IT
40、U-T Recommendation V.24 or with electrical characteristics according to ITU-T Recommendations V.10 or V.28. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the e
41、ditions indicated were valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated below. Members of IEC and IS0 maintain registers of curren
42、tly valid International Standards. IS0 4903:1989, Information technology - Data communication - 15 pole DTEYDCE interface connector and contact number assignments. ITU-T Recommendation V.11 (1994), Electrical characteristics for balanced double-current interchange circuits operating at data signalin
43、g rates up to IO Mbit/s. CCITT Recommendation X.24 (1989), List of definitions for interchange circuits between data tenninal equipment (DTE) and data circuit-terminating equipment (DCE) on public data networks (PDN). 1) Previously CCIIT Recommendation. Only one type of DTE to DTE interconnection co
44、nfiguration is considered for point-to-point connections with interfaces according to CCITT Recommendation X.24; this being shown in figure 1. There are two lines of demarcation between the two interconnecting DTEs, one located at each DTE connector. The adaptor and any cable linking these two DTE c
45、onnectors are not part of either DTE. Intermediate balanced pair cable may be provided with a maximum length mainly dependent on the parameters of the electrical characteristics of the interchange circuits and the data signalling rate. Lines of demarcation I I I I I I I 1 X.24 DTE 1 t 1 c 15-pole co
46、nnectors X.24 DTE Figure 1 - DTE interconnection configuration ISOAEC 8481:1996(E) 0 ISOAEC 4 Interchange circuit requirements The interchange circuit requirements are specified in terms of electrical, functional, mechanical and interchange point cross-over characteristics. 4.1 Electrical characteri
47、stics The electrical characteristics of ITU-T Recommendation V.11 are mandatory. Appendix 1 of Recommendation V.ll gives guidance on the operational constraints imposed by the length, balance, and terminating resistance of the interconnecting cable in relation to the data signalling rate. With addit
48、ional considerations, longer distances may be possible. 4.2 Functional characteristics The functional characteristics of interchange circuits conform to CCITT Recommendation X.24 for each interface of an interconnecting DTE. The interchange circuits required are listed in the table 1 below. Table I
49、- List of X.24 circuits for DTE interconnection. X.24 circuit Interchange r I I IS0 4903 1 Circuit description1 1 designation point V.11 contact 1 remark I G T I number 1 Cable shield 1 c - C 8 Signal ground (see 4.5) A-A 2 Transmit B-B 9 I I R A-A 4 Receive B-B II s A-K 6 Signai eiement timing B-B 13 (from DCE) X A-A 7 DTE transmit signal 0-B 14 element timing I) Contact 1 is for connecting the shieids between tandem sections of shielded interface cable. 4.3 Mechanical characteristics The mechanical characteristics of the interface conform to IS0 4903. Both
