1、BRITISH STANDARD BS IEC 60300-3-6:1997 Dependability management Part 3: Application guide Section 6: Software aspects of dependability ICS 29.020BSIEC60300-3-6:1997 This British Standard, having been prepared under the direction of the Management Systems Sector Board, was published under the authori
2、ty of the Standards Board and comes into effect on 15 January1998 BSI 05-1999 ISBN 0 580 29414 5 National foreword This British Standard reproduces verbatim IEC60300-3-6:1997 and implements it as the UK national standard. The UK participation in its preparation was entrusted by Technical Committee D
3、S/1, Dependability and tetrotechnology, to Subcommittee DS/1/1, Dependability, 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 in
4、formed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this subcommittee can be obtained on request to its secretary. From 1 January1997, all IEC publications have the number 60000 added to the old number. For instance, I
5、EC27-1 has been renumbered as IEC60027-1. For a period of time during the change over from one numbering system to the other, publications may contain identifiers from both systems. Cross-references The British Standards which implement international or European publications referred to in this docu
6、ment 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 B
7、ritish 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, theCEIIEC title page, page ii, pages 1 to 18 an
8、d 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 CommentsBSIEC60300-3-6:1997 BSI 05-1999 i Contents Page National fo
9、reword Inside front cover Foreword ii Introduction 1 1 Scope 2 2 Normative references 2 3 Definitions 2 4 Software aspects 2 5 Software life cycle phases and processes 3 6 Application of dependability programmes to products containing software 3 7 Tailoring of dependability programmes 10 Annex A (in
10、formative) Typical relationship of product life cycle phases and software life cycle phases 12 Annex B (informative) Selection of dependability programme elements 13 Annex C (informative) Software life cycle processes 14 Annex D (informative) Association of the software life cycle processes with the
11、 product life cycle phases 16 Annex E (informative) Cross-references between IEC60300-2 and ISO9000-3 17 Annex F (informative) Bibliography 18ii blankBSIEC60300-3-6:1997 ii BSI 05-1999 Foreword 1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization com
12、prising all national electrotechnical committees (IEC National Committees). The object of the IEC is to promote international co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and in addition to other activities, the IEC publishes Internati
13、onal Standards. Their preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with may participate in this preparatory work. International, governmental and non-governmental organizations liaising with the IEC also participate in this preparation.
14、 The IEC collaborates closely with the International Organization for Standardization (ISO) in accordance with conditions determined by agreement between the two organizations. 2) The formal decisions or agreements of the IEC on technical matters express, as nearly as possible, an international cons
15、ensus of opinion on the relevant subjects since each technical committee has representation from all interested National Committees. 3) The documents produced have the form of recommendations for international use and are published in the form of standards, technical reports or guides and they are a
16、ccepted by the National Committees in that sense. 4) In order to promote international unification, IEC National Committees undertake to apply IEC International Standards transparently to the maximum extent possible in their national and regional standards. Any divergence between the IEC Standard an
17、d the corresponding national or regional standard shall be clearly indicated in the latter. 5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any equipment declared to be in conformity with one of its standards. 6) Attention is drawn to the poss
18、ibility that some of the elements of this International Standard may be the subject of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights. International Standard IEC60300-3-6 has been prepared by IEC technical committee 56: Dependability. The text of t
19、his standard is based on the following documents: Full information on the voting for the approval of this standard can be found in the report on voting indicated in the above table. Annex A, Annex B, Annex C, Annex D, Annex E and Annex F are for information only. FDIS Report on voting 56/583/FDIS 56
20、/600/RVDBSIEC60300-3-6:1997 BSI 05-1999 1 Introduction Dependability is the collective term describing the availability performance of a system or product. The availability performance is influenced by the reliability, maintainability and maintenance support performance factors. In many systems and
21、products, reliability, maintainability, and availability rank amongst the dominant performance characteristics of importance to the users seeking cost-effective operation. Reliability and maintainability are performance characteristics inherent to the product design. Maintenance support is external
22、to the product itself, and will affect the quality of service. Maintenance support performance reflects the ability of the maintenance organization to provide the necessary resources to sustain a level of maintenance support effort to achieve availability performance objectives. A dependability prog
23、ramme must be tailored to the product for effective application. The dependability programme should form part of the overall project management programme for proper coordination with product development, manufacture, verification and deployment. Dependability programme elements and tasks should be c
24、onsistent with the other support programmes such as quality management, configuration management, data collection etc. The dependability management process includes project planning, specification, design analysis, verification and validation, implementation, evaluation, and data feedback of the pro
25、duct or service. Modern systems and products often contain software as a functional entity to achieve operational performance objectives. The software contained in the system or embedded in the product is subject to the dependability management process. This application guide addresses the software
26、aspects of dependability. It provides specific guidance on the selection and application of relevant activities in dependability programmes associated with products containing software, or systems configured by software with hardware elements. The availability performance of a product can be affecte
27、d by hardware failures, software faults, or human errors. Product malfunction causing downtimes can be traceable to its internal design anomalies, or due to external interference including procedural errors. Product failures can arise from internal design faults relating to hardware or software prob
28、lems. Failed hardware and worn-out parts can be identified and isolated, repaired or replaced to maintain the same level of product reliability. Unlike most physical hardware, software, once created in the form of codes or instructions, will not wear-out or deteriorate. Hence, some of the software p
29、rocesses may be different from those applicable for the hardware implementation. The intent of this application guide is to relate the software life cycle processes with the product life cycle phases within the dependability management framework. Dependability management is defined in IEC60300-1. De
30、pendability programme elements and tasks are specified in IEC60300-2. This application guide complements IEC60300-2 in terms of dependability programme implementation of systems or products containing software. Emphasis is placed on the time-phase application of relevant software activities associat
31、ed with the implementation of IEC60300-2 as shown in Annex A. Annex B presents the selection of dependability programme elements associated with the software life cycle phases. Efforts have been made to harmonize this application guide with ISO/IEC12207 on software life cycle processes. An overview
32、of the software life cycle processes is provided in Annex C. Cross-references are identified in Annex D to facilitate association of software life cycle processes with relevant dependability elements and product life cycle phases. The relationship of dependability (IEC60300 series of standards) and
33、quality (ISO9000 series of standards) is addressed in IEC60300-1/ISO9000-4 and will not be elaborated in this application guide. However, the guidelines contained in ISO9000-3 for application of ISO9001 to software should be noted in terms of quality factors influencing the dependability characteris
34、tics of software elements. Cross-references between IEC60300-2 and ISO9000-3 are shown in Annex E. A bibliography is provided in Annex F for additional references to software aspects of dependability.BSIEC60300-3-6:1997 2 BSI 05-1999 1 Scope This application guide complements IEC60300-2 and provides
35、 guidance for selection and application of dependability elements and tasks with respect to systems or products containing software. This application guide is intended for use by project managers, contract administrators, product designers, software developers, dependability specialists, quality spe
36、cialists, support personnel and system maintainers who contribute to the dependability of products or systems. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this section of IEC60300-3. At the time of public
37、ation, the editions indicated were valid. All normative documents are subject to revision, and parties to agreements based on this section of IEC60300-3 are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. Members of IEC and I
38、SO maintain registers of currently valid International Standards. IEC60050(191):1990, International Electrotechnical Vocabulary (IEV) Chapter191:Dependability and quality of service. IEC60300-1/ISO9000-4:1993, Dependability management Part 1: Dependability programme management. IEC60300-2:1995, Depe
39、ndability management Part 2: Dependability programme elements and tasks. IEC61160:1992, Formal design review. Amendment 1 (1994) ISO8402:1994, Quality management and quality assurance Vocabulary. 3 Definitions For the purpose of this section of IEC60300-3, the terms and definitions of IEC60050(191)
40、and ISO8402 apply. 4 Software aspects The software aspects of dependability deal with the specific software issues in the establishment and implementation of a dependability programme for a system or product containing software. Emphasis is placed on achieving dependability in the product design and
41、 performance objectives in reliability, maintainability and maintenance support. In the application of a dependability programme to a system or product, it is important to address the dependability issue from a system view point. A product is an entity which may contain hardware or software componen
42、ts or both. A system is an integrated composite entity, which may include the product, supply material, personnel, and related support facilities and services. The system environment defines the operating conditions and interactions of the system components. The availability performance of the syste
43、m is measured or assessed to validate the achievement of stated dependability objectives in terms of reliability, maintainability, and maintenance support. Dependability is a collective measure of the performances of a system in its actual state of application or use, with or without the operation o
44、f specific software functions which may form part of an integrated system. It should be noted that software cannot function by itself but forms part of a system to provide specific application. Software is a medium for realization of a system performance objective. Software is characterized in parti
45、cular by its application function, operating environment, size, language and complexity, installation and upgrade processes. The software aspects of dependability address the software components within a system in the context of dependability performance of the system. They do not address the qualit
46、y of the software as a stand alone item. Software quality is described in ISO/IEC9126 1 1) . The software aspects of dependability are associated with the integrity of the software component in system operation. Integrity is an inherent design attribute associated with risk containment. Risk is an u
47、ndesirable exposure or threat associated with the system operation. Risk is characterized by its probability of occurrence and its impact or consequence of the event outcome. The ability of a system and its software component to contain risk is dependent on the system architecture, fault tolerant de
48、sign, and the degree of rigour in the application of relevant methods to the software. The integrity level is the assigned risk associated with the system operation which is to be contained. The relationship between dependability and integrity is closely linked by the criticality of software applica
49、tion associated with the assigned integrity levels when dealing with the software affecting system performance. 1) Figures in square brackets refer to the bibliography given in Annex F.BSIEC60300-3-6:1997 BSI 05-1999 3 5 Software life cycle phases and processes The life cycle of software is very much intertwined with the life cycle of its parent system. A typical relationship of the software life cycle phases and the conventional product life cycle phases in accordance with IEC60300-1/ISO9000-4 is shown in Annex A. An example for the selection of dependability p