1、 Reference number ISO/TR 18492:2005(E) ISO 2005TECHNICAL REPORT ISO/TR 18492 First edition 2005-10-01 Long-term preservation of electronic document-based information Conservation long terme dinformation document base lectronique ISO/TR 18492:2005(E) PDF disclaimer This PDF file may contain embedded
2、typefaces. In accordance with Adobes licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In downloading this file, parties accept therein the responsibility of not i
3、nfringing Adobes licensing policy. The ISO Central Secretariat accepts no liability in this area. Adobe is a trademark of Adobe Systems Incorporated. Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation parameters were
4、optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below. ISO 2005 All rights reserved. Unless otherwise specified
5、, 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 either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Case p
6、ostale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org Published in Switzerland ii ISO 2005 All rights reservedISO/TR 18492:2005(E) ISO 2005 All rights reserved iii Contents Page Foreword iv Introduction v 1 Scope 1 2 Normative references 1 3
7、 Terms and definitions .2 4 Symbols and abbreviated terms 3 5 Long-term preservation 3 5.1 General3 5.2 Goals of a long-term preservation strategy 4 6 Elements of a long-term preservation strategy 7 6.1 General7 6.2 Media renewal 7 6.3 Metadata .10 6.4 Migrating electronic document-based information
8、11 7 Developing a long-term preservation strategy .14 7.1 Long-term preservation policy.14 7.2 Quality control14 7.3 Security.15 7.4 Environmental control and monitoring .16 Annex A (informative) National electronic records programmes and other selected publications .17 ISO/TR 18492:2005(E) iv ISO 2
9、005 All rights reservedForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in
10、a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commissi
11、on (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical c
12、ommittees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. In exceptional circumstances, when a technical committee has collected data of a different kind from that which is normally publi
13、shed as an International Standard (“state of the art”, for example), it may decide by a simple majority vote of its participating members to publish a Technical Report. A Technical Report is entirely informative in nature and does not have to be reviewed until the data it provides are considered to
14、be no longer valid or useful. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO/TR 18492 was prepared by Technical Committee ISO/TC 171, Document m
15、anagement applications, Subcommittee SC 3, General issues. ISO/TR 18492:2005(E) ISO 2005 All rights reserved v Introduction Ensuring the long-term preservation of authentic electronic document-based information is a well-documented and identified problem within many fields of expertise, including ar
16、chival science, document management, e-commerce, e-governance and technology development. As an additional problem, individuals and organizations charged with the responsibility for ensuring long-term access to authentic electronic document-based information have employed a diversity of strategies d
17、esigned to achieve this goal. Although there is a clear need to address the problem of long-term access to authentic electronic document-based information, there is a current lack of harmonized international guidance on these issues. This has led to diverse and, sometimes, incompatible approaches th
18、at can give rise to potentially mission-critical problems, regarding the accessibility and/or authenticity of the electronic document-based information being retained. Acknowledging the generic technological obsolescence problem of computer hardware and software as well as the limited life of digita
19、l storage media, this Technical Report provides guidance to storage repositories in providing access to and maintaining authentic electronic document-based information that has been retained for future reference. The purpose of this Technical Report is to provide a clear framework for strategy devel
20、opment and best practices that can be applied to a broad range of public and private sector electronic document-based information to ensure its long-term accessibility and authenticity. TECHNICAL REPORT ISO/TR 18492:2005(E) ISO 2005 All rights reserved 1 Long-term preservation of electronic document
21、-based information 1 Scope This Technical Report provides practical methodological guidance for the long-term preservation and retrieval of authentic electronic document-based information, when the retention period exceeds the expected life of the technology (hardware and software) used to create an
22、d maintain the information. It takes into account the role of technology neutral information technology standards in supporting long-term access. This guidance also acknowledges that ensuring the long-term preservation and retrieval of authentic electronic document-based information should involve I
23、T specialists, document managers, records managers and archivists. It does not cover processes for the creation, capture and classification of authentic electronic document-based information. This Technical Report applies to all forms of information generated by information systems and saved as evid
24、ence of business transactions and activities. NOTE Electronic document-based information constitutes the “business memory” of daily business actions or events and enables entities to later review, analyse or document these actions and events. As such, this electronic document-based information is ev
25、idence of business transactions that enable entities to support current and future management decisions, satisfy customers, achieve regulatory compliance and protect against adverse litigation. To achieve this goal, this electronic document-based information should be retained and appropriately pres
26、erved. 2 Normative references The following referenced documents are indispensable for the application 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 12651:1999, Ele
27、ctronic imaging Vocabulary ISO 15489-1, Information and documentation Records management Part 1: General ISO/TR 15489-2, Information and documentation Records management Part 2: Guidelines ISO/TS 23081-1, Information and documentation Records management processes Metadata for records Part 1: Princip
28、les ISO/TR 18492:2005(E) 2 ISO 2005 All rights reserved3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 12651, ISO 15489-1 and ISO/TR 15489-2 and the following apply. 3.1 authentic electronic document-based information electronic document-based inform
29、ation the accuracy, reliability and integrity of which are maintained over time 3.2 document-based information substantive information that can be treated as a unit (e.g. an image, text, spreadsheet, database views) NOTE Document-based information is inclusive of, but not necessarily limited to: tex
30、t, images, tabular data (e.g. a spreadsheet), or any combination thereof. 3.3 document-based information content substantive content contained in document-based information 3.4 document-based information context information about the circumstances of electronic document-based information creation, c
31、ontrol, use, storage and management, and information about its relationship to other similar material 3.5 document-based information structure logical and physical attributes of document-based information NOTE Logical attributes consist of the logical order, e.g. a hierarchy with identifiable subpar
32、ts, whereas physical attributes comprise elements, e.g. type font, spacing. 3.6 electronic archiving storage of electronic information in an independent physical or logical space where the information is protected from loss, alteration and deterioration NOTE The information may be used as reliable e
33、vidence in the future if it has been protected in this manner. 3.7 long-term preservation period of time that electronic document-based information is maintained as accessible and authentic evidence NOTE This period of time can range between a few years to hundreds of years, depending upon the needs
34、 and requirements of the organization. For some organizations, this period of time would be determined by regulatory compliance, legal requirements and business needs. For other oranizations, such as archival repositories holding public records, the period of time required to retain electronic docum
35、ent-based information is usually thought to be hundreds of years. 3.8 metadata data describing the content (including indexing terms for retrieval), context and structure of electronic document-based information and their management over time 3.9 migration process of transferring electronic document
36、-based information from one software/hardware environment or storage medium to another environment or storage medium with little or no alteration of structure and no alteration in content and context ISO/TR 18492:2005(E) ISO 2005 All rights reserved 3 3.10 storage repository storage repository organ
37、ization or entity charged with the storage and maintenance of authentic electronic document-based information NOTE It is recognized that this definition is different from technical definitions of “storage repositories”. 3.11 technological obsolescence displacement of an established technical solutio
38、n in a marketplace as a result of major technological developments or improvements 4 Symbols and abbreviated terms ASCII American Standard Code for Information Interchange CRC Cyclical Redundancy Code HTML Hyper Text Markup Language JPEG Joint Photographic Engineers Group OCR Optical Character Recog
39、nition PDF/A-1 Portable Document Format Archive SHA-1 Standard Hash Algorithm 1 TIFF Tagged Image File Format WORM Write Once Read Many (times) XML Extensible Markup Language 5 Long-term preservation 5.1 General Increasingly, the proliferation of computer technologies that support the creation, use,
40、 storage and maintenance of information, results in private and public sector organizations relying on electronic document-based information as the official evidence of their business activities. Consequently, organizations increasingly face the challenge of ensuring the long-term accessibility of a
41、uthentic electronic information that was created within reliable and trustworthy information systems and stored on electronic media that might be subject to technological obsolescence that if left uncorrected will make the document-based information irretrievable. The importance of this problem is c
42、ompounded by the fact that organizations are increasingly conducting activities and transactions where no paper evidence exists. It is essential, therefore, that organizations develop and apply a well-defined strategy for providing long-term preservation and retrieval of authentic electronic documen
43、t-based information. Subclause 5.2 defines the elements of such a strategy. ISO/TR 18492:2005(E) 4 ISO 2005 All rights reserved5.2 Goals of a long-term preservation strategy 5.2.1 General This subclause identifies six key issues that storage repositories should consider when they are developing a lo
44、ng-term preservation strategy. 5.2.2 Readable electronic document-based information A long-term preservation strategy should ensure that electronic document-based information remains readable into the future. To achieve this, the bit stream comprising electronic document-based information should be
45、accessible on the computer system or device that: initially created it or currently stores it or currently accesses it or will be used to store the electronic information in the future. These four processablity options are predicated on the fact that electronic document-based information stored on d
46、igital storage media can become unreadable. There are two primary ways in which this can occur. One is the result of exposure to hostile storage conditions. All of the media currently used for storing electronic document-based information share a common vulnerability to poor environmental conditions
47、, e.g. fluctuations in temperature and humidity. These adverse conditions either damage the media or accelerate the ageing process. Different types of digital storage media require different levels of controlled storage environment to ensure maximum longevity. Some storage technologies are prone to
48、data corruption through magnetic field interference, dust and environmental contaminants (magnetic storage media), while others (optical storage media) are not as prone to these outside factors and less susceptible to media damage outside tightly controlled storage environments. Regardless of which
49、storage technology is in use, it is important to recognize that all forms of storage media can deteriorate and/or degrade through environmental changes. The second is that non-readability may occur through media obsolescence, which occurs when a storage device (e.g. a tape or disk) is physically incompatible with the available computer hardware (e.g. a tape or disk drive) and therefore cannot be read. Based on past trends, media obsolescence in the future seems inevitable because advances in storage technology continually
