1、 Reference number ISO/IEC 8824-2:2015(E) ISO/IEC 2015INTERNATIONAL STANDARD ISO/IEC 8824-2 Fifth edition 2015-11-15 Information technology Abstract Syntax Notation One (ASN.1): Information object specification Technologies de linformation Notation de syntaxe abstraite numro un (ASN.1): Spcification
2、des objets informationnels ISO/IEC 8824-2:2015(E) COPYRIGHT PROTECTED DOCUMENT ISO/IEC 2015 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting o
3、n the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrighti
4、so.org Web www.iso.org Published in Switzerland ii ISO/IEC 2015 All rights reservedISO/IEC 8824-2:2015(E) ISO/IEC 2015 All rights reserved iiiForeword ISO (the International Organization for Standardization) and IEC (the International Electrotechnical Commission) form the specialized system for worl
5、dwide 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 committees collaborate i
6、n 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. International Standards are dra
7、fted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of the joint technical committee is to prepare International Standards. Draft International Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as an Inte
8、rnational Standard requires approval by at least 75 % of the national bodies casting a vote. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
9、This fifth edition cancels and replaces the fourth edition of ISO/IEC 8824-2:2008 which has been technically revised. It also incorporates ISO/IEC 8824-2:2008/Cor.1:2012. ISO/IEC 8824-2 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology, Subcommittee SC 6, Telecommunicat
10、ions and information exchange between systems, in collaboration with ITU-T. The identical text is published as ITU-T X.681 (08/2015). I n t e r n a t i o n a l T e l e c o m m u n i c a t i o n U n i o n ITU-T X.681 TELECOMMUNICATION STANDARDIZATION SECTOR OF ITU (08/2015) SERIES X: DATA NETWORKS, O
11、PEN SYSTEM COMMUNICATIONS AND SECURITY OSI networking and system aspects Abstract Syntax Notation One (ASN.1) Information technology Abstract Syntax Notation One (ASN.1): Information object specification Recommendation ITU-T X.681 ITU-T X-SERIES RECOMMENDATIONS DATA NETWORKS, OPEN SYSTEM COMMUNICATI
12、ONS AND SECURITY PUBLIC DATA NETWORKS Services and facilities X.1X.19 Interfaces X.20X.49 Transmission, signalling and switching X.50X.89 Network aspects X.90X.149 Maintenance X.150X.179 Administrative arrangements X.180X.199 OPEN SYSTEMS INTERCONNECTION Model and notation X.200X.209 Service definit
13、ions X.210X.219 Connection-mode protocol specifications X.220X.229 Connectionless-mode protocol specifications X.230X.239 PICS proformas X.240X.259 Protocol Identification X.260X.269 Security Protocols X.270X.279 Layer Managed Objects X.280X.289 Conformance testing X.290X.299 INTERWORKING BETWEEN NE
14、TWORKS General X.300X.349 Satellite data transmission systems X.350X.369 IP-based networks X.370X.379 MESSAGE HANDLING SYSTEMS X.400X.499 DIRECTORY X.500X.599 OSI NETWORKING AND SYSTEM ASPECTS Networking X.600X.629 Efficiency X.630X.639 Quality of service X.640X.649 Naming, Addressing and Registrati
15、on X.650X.679 Abstract Syntax Notation One (ASN.1) X.680X.699 OSI MANAGEMENT Systems management framework and architecture X.700X.709 Management communication service and protocol X.710X.719 Structure of management information X.720X.729 Management functions and ODMA functions X.730X.799 SECURITY X.
16、800X.849 OSI APPLICATIONS Commitment, concurrency and recovery X.850X.859 Transaction processing X.860X.879 Remote operations X.880X.889 Generic applications of ASN.1 X.890X.899 OPEN DISTRIBUTED PROCESSING X.900X.999 INFORMATION AND NETWORK SECURITY X.1000X.1099 SECURE APPLICATIONS AND SERVICES X.11
17、00X.1199 CYBERSPACE SECURITY X.1200X.1299 SECURE APPLICATIONS AND SERVICES X.1300X.1399 CYBERSECURITY INFORMATION EXCHANGE X.1500X.1599 CLOUD COMPUTING SECURITY X.1600X.1699 For further details, please refer to the list of ITU-T Recommendations. Rec. ITU-T X.681 (08/2015) i INTERNATIONAL STANDARD IS
18、O/IEC 8824-2 RECOMMENDATION ITU-T X.681 Information technology Abstract Syntax Notation One (ASN.1): Information object specification Summary Recommendation ITU-T X.681 | ISO/IEC 8824-2 provides the ASN.1 notation which allows information object classes as well as individual information objects and
19、sets thereof to be defined and given reference names. An information object class defines the form of a conceptual table (an information object set) with one column for each field in the information object class, and with each complete row defining an information object. History Edition Recommendati
20、on Approval Study Group Unique ID *1.0 ITU-T X.681 1994-07-01 7 11.1002/1000/3042 1.1 ITU-T X.681 (1994) Amd. 1 1995-04-10 7 11.1002/1000/3043 2.0 ITU-T X.681 1997-12-12 7 11.1002/1000/4444 2.1 ITU-T X.681 (1997) Technical Cor. 1 1999-06-18 7 11.1002/1000/4702 2.2 ITU-T X.681 (1997) Amd. 1 1999-06-1
21、8 7 11.1002/1000/4701 2.3 ITU-T X.681 (1997) Amd. 2 2001-10-29 7 11.1002/1000/5564 3.0 ITU-T X.681 2002-07-14 17 11.1002/1000/6086 3.1 ITU-T X.681 (2002) Amd. 1 2003-10-29 17 11.1002/1000/7020 3.2 ITU-T X.681 (2002) Technical Cor. 1 2006-06-13 17 11.1002/1000/8837 3.3 ITU-T X.681 (2002) Technical Co
22、r. 2 2007-05-29 17 11.1002/1000/9106 4.0 ITU-T X.681 2008-11-13 17 11.1002/1000/9605 4.1 ITU-T X.681 (2008) Cor. 1 2011-10-14 17 11.1002/1000/11377 5.0 ITU-T X.681 2015-08-13 17 11.1002/1000/12480 *To access the Recommendation, type the URL http:/handle.itu.int/ in the address field of your web brow
23、ser, followed by the Recommendations unique ID. For example, http:/handle.itu.int/11.1002/1000/11830-en. ii Rec. ITU-T X.681 (08/2015) FOREWORD The International Telecommunication Union (ITU) is the United Nations specialized agency in the field of telecommunications, information and communication t
24、echnologies (ICTs). The ITU Telecommunication Standardization Sector (ITU-T) is a permanent organ of ITU. ITU-T is responsible for studying technical, operating and tariff questions and issuing Recommendations on them with a view to standardizing telecommunications on a worldwide basis. The World Te
25、lecommunication Standardization Assembly (WTSA), which meets every four years, establishes the topics for study by the ITU-T study groups which, in turn, produce Recommendations on these topics. The approval of ITU-T Recommendations is covered by the procedure laid down in WTSA Resolution 1. In some
26、 areas of information technology which fall within ITU-Ts purview, the necessary standards are prepared on a collaborative basis with ISO and IEC. NOTE In this Recommendation, the expression “Administration“ is used for conciseness to indicate both a telecommunication administration and a recognized
27、 operating agency. Compliance with this Recommendation is voluntary. However, the Recommendation may contain certain mandatory provisions (to ensure, e.g., interoperability or applicability) and compliance with the Recommendation is achieved when all of these mandatory provisions are met. The words
28、“shall“ or some other obligatory language such as “must“ and the negative equivalents are used to express requirements. The use of such words does not suggest that compliance with the Recommendation is required of any party. INTELLECTUAL PROPERTY RIGHTS ITU draws attention to the possibility that th
29、e practice or implementation of this Recommendation may involve the use of a claimed Intellectual Property Right. ITU takes no position concerning the evidence, validity or applicability of claimed Intellectual Property Rights, whether asserted by ITU members or others outside of the Recommendation
30、development process. As of the date of approval of this Recommendation, ITU had not received notice of intellectual property, protected by patents, which may be required to implement this Recommendation. However, implementers are cautioned that this may not represent the latest information and are t
31、herefore strongly urged to consult the TSB patent database at http:/www.itu.int/ITU-T/ipr/. ITU 2015 All rights reserved. No part of this publication may be reproduced, by any means whatsoever, without the prior written permission of ITU. Rec. ITU-T X.681 (08/2015) iii CONTENTS Page Introduction . i
32、v 1 Scope 1 2 Normative references 1 2.1 Identical Recommendations | International Standards . 1 3 Definitions 1 3.1 Specification of basic notation 1 3.2 Constraint specification . 1 3.3 Parameterization of ASN.1 specification 1 3.4 Additional definitions 2 4 Abbreviations . 3 5 Convention . 3 6 No
33、tation 3 6.1 Assignments 3 6.2 Types . 3 6.3 Values 4 6.4 Elements 4 7 ASN.1 lexical items 4 7.1 Information object class references . 4 7.2 Information object references 4 7.3 Information object set references 4 7.4 Type field references . 4 7.5 Value field references 4 7.6 Value set field referenc
34、es 5 7.7 Object field references 5 7.8 Object set field references . 5 7.9 Word . 5 7.10 Additional keywords . 5 8 Referencing definitions . 5 9 Information object class definition and assignment 6 10 Syntax List 9 11 Information object definition and assignment. 12 12 Information object set definit
35、ion and assignment . 14 13 Associated tables 15 14 Notation for the object class field type . 16 15 Information from objects 18 Annex A The TYPE-IDENTIFIER information object class . 21 Annex B Abstract syntax definitions 22 Annex C The instance-of type. 23 Annex D Examples . 25 D.1 Example usage of
36、 simplified OPERATION class . 25 D.2 Example usage of “ObjectClassFieldType“ 26 D.3 Illustrate usage of objects and object sets 26 Annex E Tutorial annex on the ASN.1 model of object set extension 28 Annex F Summary of the notation 29 iv Rec. ITU-T X.681 (08/2015) Introduction An application designe
37、r frequently needs to design a protocol which will work with any of a number of instances of some class of information objects, where instances of the class may be defined by a variety of other bodies, and may be added to over time. Examples of such information object classes are the “operations“ of
38、 Remote Operations Service (ROS) and the “attributes“ of the OSI Directory. This Recommendation | International Standard provides notation which allows information object classes as well as individual information objects and information object sets thereof to be defined and given reference names. An
39、 information object class is characterized by the kinds of fields possessed by its instances. A field may contain: an arbitrary type (a type field); or a single value of a specified type (a fixed-type value field); or a single value of a type specified in a (named) type field (a variable-type value
40、field); a non-empty set of values of a specified type (a fixed-type value set field); or a non-empty set of values of a type specified in a (named) type field (a variable-type value set field); or a single information object from a specified information object class (an object field); an information
41、 object set from a specified information object class (an object set field). A fixed-type value field of an information object class may be selected to provide unique identification of information objects in that class. This is called the identifier field for that class. Values of the identifier fie
42、ld, if supplied, are required to be unique within any information object set that is defined for that class. They may, but need not, serve to unambiguously identify information objects of that class within some broader scope, particularly by the use of object identifier as the type of the identifier
43、 field. An information object class is defined by specifying: the names of the fields; for each field, the form of that field (type, fixed-type value, variable-type value, fixed-type value set, variable-type value set, object, or object set); optionality and default settings of fields; which field,
44、if any, is the identifier field. An individual information object in the class is defined by providing the necessary information for each field. The notation defined herein permits an ASN.1 type to be specified by reference to a field of some information object class the object class field type. In
45、Rec. ITU-T X.682 | ISO/IEC 8824-3, notation is provided to enable this type to be restricted by reference to some specific information object set. It can be useful to consider the definition of an information object class as defining the form of an underlying conceptual table (the associated table)
46、with one column for each field, and with a completed row defining an information object. The form of the table (determined by the information object class specification) determines the sort of information to be collected and used to complete some protocol specification. The underlying conceptual tab
47、le provides the link between those specifying information objects of that class and the protocol which needs that information to complete its specification. Typically, the actual information object set used to complete a particular protocol specification will be a parameter of that protocol (see Rec
48、. ITU-T X.683 | ISO/IEC 8824-4). The “InformationFromObjects“ notation referencing a specific object or object set (probably a parameter) can be used to extract information from cells of conceptual tables. This Recommendation | International Standard: Specifies a notation for defining an information
49、 object class, and for identifying it with a reference name (see clause 9). Specifies a notation by which the definer of an information object class can provide a defined syntax for the definition of information objects of that class; a default notation is provided for classes for which no defined syntax has been defined (see clause 10). Specifies a notation for defining an information object, and for assigning it to a reference name (see clause 11), and provides analogous no
