1、BSI Standards Publication PD ISO/TR 17797:2014 Electronic archiving Selection of digital storage media for long term preservationPD ISO/TR 17797:2014 PUBLISHED DOCUMENT National foreword This Published Document is the UK implementation of ISO/TR 17797:2014. The UK participation in its preparation wa
2、s entrusted to Technical Committee IDT/1, Document Management Applications. A list of organizations represented on this committee can be obtained on request to its secretary. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correc
3、t application. The British Standards Institution 2014. Published by BSI Standards Limited 2014 ISBN 978 0 580 82610 8 ICS 37.080 Compliance with a British Standard cannot confer immunity from legal obligations. This Published Document was published under the authority of the Standards Policy and Str
4、ategy Committee on 30 September 2014. Amendments issued since publication Date Text affectedPD ISO/TR 17797:2014 ISO 2014 Electronic archiving Selection of digital storage media for long term preservation Archivage lectronique Slection dun support de stockage numrique pour une prservation long terme
5、 TECHNICAL REPORT ISO/TR 17797 First edition 2014-10-01 Reference number ISO/TR 17797:2014(E)PD ISO/TR 17797:2014ISO/TR 17797:2014(E)ii ISO 2014 All rights reserved COPYRIGHT PROTECTED DOCUMENT ISO 2014 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or
6、 utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on 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 co
7、pyright office Case postale 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 SwitzerlandPD ISO/TR 17797:2014ISO/TR 17797:2014(E) ISO 2014 All rights reserved iii Contents Page Foreword v Introduction vi 1 Scope . 1 2 Normative ref
8、erences 1 3 T erms and definitions . 1 4 Methodology . 1 5 Choice of storage system/media 2 6 Hard disk drive . 3 6.1 General . 3 6.2 Reasons for failure . 3 6.3 Quality indicators . 4 6.4 Technical arrangements 7 6.5 Control tools 8 7 Magnetic tape . 9 7.1 General . 9 7.2 Reasons for failure . 9 7.
9、3 Quality indicators 10 7.4 Technical arrangements .10 7.5 Control tools .11 8 S olid stat e dri v e (SDD), flash memory 11 8.1 General 11 8.2 Reasons for failure 12 8.3 Quality indicators 12 8.4 Technical arrangements .12 8.5 Control tools .13 9 Optical discs (recordable and rewritable) .14 9.1 Gen
10、eral 14 9.2 Reasons for failure 14 9.3 Quality indicators 14 9.4 Technical arrangements .15 9.5 Control tools .16 10 General requirements for long-term preservation .17 10.1 General 17 10.2 Media traceability 17 10.3 Optimal storage identification 17 10.4 Duplication of storage 17 10.5 Media stockta
11、king .17 10.6 Periodic inspection .18 11 Selection of media 18 11.1 General 18 11.2 Volume of information .18 11.3 Size of individual items .18 11.4 Retention period of the information .19 11.5 Capacity of the media .19 11.6 Technology already in use within the organization .19 11.7 Retrieval and ac
12、cessibility requirements 19 11.8 Exposure to threats to media 20 11.9 Costs 20 11.10 Records management, regulatory, and discovery 20 11.11 Technology refresh cycle/software migration 20PD ISO/TR 17797:2014ISO/TR 17797:2014(E)iv ISO 2014 All rights reserved 11.12 Industry acceptance and maturity 20
13、Annex A (informative) RAID .21 Annex B (informative) SMART 23 Bibliography .24PD ISO/TR 17797:2014ISO/TR 17797:2014(E) Foreword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Sta
14、ndards is normally carried out through ISO technical committees. Each member body interested in 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
15、take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In
16、 particular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives). Attention is drawn to the possibility that some of the element
17、s of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (
18、see www.iso.org/patents). Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement. For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adheren
19、ce to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information The committee responsible for this document is ISO/TC 171, Document management applications, Subcommittee SC 1, Quality. ISO 2014 All rights reserved vPD ISO/TR 17797:2014ISO
20、/TR 17797:2014(E) Introduction A significant proportion of digital information generated by different human activities will need to be stored for a long period of time and in some cases for as long as it is possible. Where long-term is used in this Technical Report, a storage period of not less than
21、 the anticipated life of the storage media is assumed. The media currently used to store digital information for the long-term have not been analysed and manufactured for this purpose but mainly developed to maximize transfer rates, density recording, and access time. All these parameters have to be
22、 taken in perspective when long-term preservation is the requirement, not just simple backup purposes. In general, current information management systems might not be conducive to the satisfactory achievement of long-term preservation. For long-term preservation, there needs to be the development of
23、 special resources and complex procedures with often increased costs when compared with normal information management systems (duplication of files, refreshing storage, equipment redundancy, monitoring systems, heavy maintenance, frequent and risky migration, high energy consumption, etc.). Even whe
24、n a system is designed for long-term preservation, the day-to-day requirements for access and management of the stored digital information needs to be taken into consideration. When designing systems for long-term preservation, it is necessary to have specific pathways with the objective of providin
25、g qualified storage media on criteria such as reliability and stability; this would ensure that the sustainability of digital information leads to optimize the solution for both long-term preservation and access to digital information. The context of the requirement for long-term digital preservatio
26、n needs to establish conditions and recommendations for media that is specially manufactured with a guaranteed potential of stability and reliability. The main criteria involved in the long-term preservation of digital information can be summarized as follows: a) intrinsic stability of storage media
27、; b) stability of physical and/or chemical modifications of media produced by record processing; c) quality and reliability of recording process; d) preservation of access path to information and metadata; e) preservation of access tools (i.e. any special software needed to use digital items that ha
28、ve not been migrated to a long-term or standardized format); f) quality of information; compliance with format specification; data integrity. Only the first three criteria from the list above are considered as part of this Technical Report. It is noted that the objective is not to make rules or spec
29、ifications for use on information management systems as several International Standards, such as ISO 14641-1, ISO 15489-1, and ISO/TR 15489-2, fill this role.vi ISO 2014 All rights reservedPD ISO/TR 17797:2014Electronic archiving Selection of digital storage media for long term preservation 1 Scope
30、This Technical Report gives guidelines on a selection of the most appropriate storage media for use in long-term electronic storage solutions. It includes a discussion on magnetic, optical, and electronic storage. 2 Normative references The following documents, in whole or in part, are normatively r
31、eferenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 12651-1, Electronic document management Vocabulary Part 1: Electro
32、nic document imaging 3 T erms a nd definiti ons For the purposes of this document, the terms and definitions given in ISO 12651-1 and the following apply. 3.1 refreshment data migration where the media is replaced with equivalent media such that all storage hardware and software functionality is unc
33、hanged Note 1 to entry: Refreshment cycles are based on the predicted life span of the medium. SOURCE: ISO 13008:2012 3.2 migration process of moving digital information, including their existing characteristics, from one hardware or software configuration to another without changing the format Note
34、 1 to entry: Migration can also include converting to a more current computing environment, involving changes to hardware/software configurations. SOURCE: adapted from ISO 13008 3.3 storage medium device on which digital information can be recorded Note 1 to entry: Device can designate a support, a
35、combined support and media player, or a set recorder. 4 Methodology The characteristics required for storage media should be clearly established regarding the following criteria: reliability; TECHNICAL REPORT ISO/TR 17797:2014(E) ISO 2014 All rights reserved 1PD ISO/TR 17797:2014ISO/TR 17797:2014(E)
36、 anticipated longevity; sensitivity to environment (operating or storage), internal and external conditions; obsolescence of hardware and software. A part of this Technical Report describes methods or guidelines which lead to the identification of appropriate media based on criteria specified, such
37、as the following: control strategies; media evaluation process (procedures, monitoring devices); tools for monitoring characteristics (ECC, data verification, etc.); defining acceptance criteria level; analysis of means (existing or desired) for detecting trends. On this basis, this Technical Report
38、 is structured around the following points: requirements for the long-term storage media; capability of different types of technologies to store digital information in the long term, including aspects of quality, reliability, and durability; definition of criteria considered; diagnostic elements to
39、be used. 5 Choice of storage system/media This clause lists some of the issues related to the different types of media that can be used for the storage of digital information. The choice of media should support the long-term preservation strategy and the architecture of the information management sy
40、stem. All media/recording systems are at risk of a sudden loss of access to digital information, regardless of the technology, so an information management system should be designed to mitigate this risk of loss of this information. There are various reasons for loss of access, but the most common i
41、s the physical failure of media/drivers. This can be the cause in up to 70 % of cases (30 % drive read instability, 38 % drive failure). The choice of storage system/media is complex because of their often unpredictable behaviour during their life. Reliability models used by manufacturers can provid
42、e estimates that are often not achieved in the operational environment. The reliability of storage media is often given by manufacturers in terms of failure rate or in terms of lifespan; for example, the rated lifetime of a particular media type might range from 10 years to several centuries. Howeve
43、r, in practical applications it can be found that the actual lifespan can range from a few months to 20 years, as it can be shown that operational life depends upon the operating environment. This disparity needs to be taken into consideration when deciding between different types of media or differ
44、ent models of the same type of media. A further factor that should be taken into consideration when choosing storage solutions is the issue of obsolescence. Recent developments in storage systems have resulted in a very rapid increase in functional performance, but this has also lead to the rapid ob
45、solescence of implemented solutions. Moreover, reliability and lifespan are typically not transferable from old systems to newer replacements. With each new advance in technology, much of the knowledge gained by tests or various statistical studies on existing systems will need to be replaced by tri
46、als and other methods of estimating the reliability of the new systems. This requirement is not supported by research on media degradation processes which makes it very difficult to establish a model for estimating storage media life (see Bibliography).2 ISO 2014 All rights reservedPD ISO/TR 17797:2
47、014ISO/TR 17797:2014(E) Storage solutions should be chosen taking into consideration the following: results of acceptance tests; traceability of the manufacturing processes; quality testing by sampling processes; longitudinal monitoring of media/drivers; environmental conditions of operational use a
48、nd storage; continuous monitoring on the evolution of supply (hardware and software) in relation to the risk of withdrawal of commercial products. 6 Hard disk drive 6.1 General Hard disk drive (HDD) technology is well established, and over the past 50 years there have been substantial improvements i
49、n data transfer rates and capacity along with a marked decrease in product price. Hard disk drives are electromechanical devices containing generally aluminium platters that are layered with magnetic recording material. Data are written to and read from the disk by moveable read/write heads which float over the surface of the disk. Two main risks are associated with the use of hard disk drives as physical carriers. They have a short life expectancy and should be replaced every five years
