IEC 62628:2012

IEC 62628 ®
Edition 1.0 2012-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Guidance on software aspects of dependability

Lignes directrices concernant la sûreté de fonctionnement du logiciel

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IEC 62628 ®
Edition 1.0 2012-08
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Guidance on software aspects of dependability

Lignes directrices concernant la sûreté de fonctionnement du logiciel

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XB
ICS 03.120.01 ISBN 978-2-83220-303-3

– 2 – 62628 © IEC:2012
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms, definitions and abbreviations . 7
3.1 Terms and definitions . 7
3.2 Abbreviations . 9
4 Overview of software aspects of dependability . 9
4.1 Software and software systems . 9
4.2 Software dependability and software organizations . 10
4.3 Relationship between software and hardware dependability . 10
4.4 Software and hardware interaction . 11
5 Software dependability engineering and application. 12
5.1 System life cycle framework . 12
5.2 Software dependability project implementation . 12
5.3 Software life cycle activities . 13
5.4 Software dependability attributes . 14
5.5 Software design environment . 15
5.6 Establishing software requirements and dependability objectives . 15
5.7 Classification of software faults . 16
5.8 Strategy for software dependability implementation . 17
5.8.1 Software fault avoidance . 17
5.8.2 Software fault control . 17
6 Methodology for software dependability applications . 18
6.1 Software development practices for dependability achievement . 18
6.2 Software dependability metrics and data collection . 18
6.3 Software dependability assessment . 19
6.3.1 Software dependability assessment process . 19
6.3.2 System performance and dependability specification . 20
6.3.3 Establishing software operational profile . 21
6.3.4 Allocation of dependability attributes . 21
6.3.5 Dependability analysis and evaluation . 22
6.3.6 Software verification and software system validation . 24
6.3.7 Software testing and measurement . 25
6.3.8 Software reliability growth and forecasting . 28
6.3.9 Software dependability information feedback . 29
6.4 Software dependability improvement . 29
6.4.1 Overview of software dependability improvement . 29
6.4.2 Software complexity simplification . 29
6.4.3 Software fault tolerance . 30
6.4.4 Software interoperability . 30
6.4.5 Software reuse . 31
6.4.6 Software maintenance and enhancement . 31
6.4.7 Software documentation . 32
6.4.8 Automated tools . 33
6.4.9 Technical support and user training . 33

62628 © IEC:2012 – 3 –
7 Software assurance . 34
7.1 Overview of software assurance . 34
7.2 Tailoring process . 34
7.3 Technology influence on software assurance. 34
7.4 Software assurance best practices . 35
Annex A (informative) Categorization of software and software applications . 37
Annex B (informative) Software system requirements and related dependability
activities . 39
Annex C (informative) Capability maturity model integration process . 43
Annex D (informative) Classification of software defect attributes . 46
Annex E (informative) Examples of software data metrics obtained from data collection . 50
Annex F (informative) Example of combined hardware/software reliability functions . 53
Annex G (informative) Summary of software reliability model metrics . 55
Annex H (informative) Software reliability models selection and application . 56
Bibliography . 59

Figure 1 – Software life cycle activities . 14
Figure F.1 – Block diagram for a monitoring control system . 53

Table C.1 – Comparison of capability and maturity levels . 43
Table D.1 – Classification of software defect attributes when a fault is found . 46
Table D.2 – Classification of software defect attributes when a fault is fixed . 47
Table D.3 – Design review/code inspection activity to triggers mapping . 47
Table D.4 – Unit test activity to triggers mapping . 48
Table D.5 – Function test activity to triggers mapping . 48
Table D.6 – System test activity to triggers mapping . 49
Table H.1 – Examples of software reliability models . 57

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INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
GUIDANCE ON SOFTWARE ASPECTS OF DEPENDABILITY

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of 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, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). 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. 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 IEC on technical matters express, as nearly as possible, an international
...