1、IEEE Std 982.1-2005(Revision of IEEE Std 982.1-1988)IEEE Standard Dictionary ofMeasures of the Software Aspectsof DependabilityI E E E3 Park Avenue New York, NY 10016-5997, USA8 May 2006IEEE Computer SocietySponsored by theSoftware Engineering Standards Committee IEEE Std 982.1-2005 (Revision of IEE
2、E Std 982.1-1988) IEEE Standard Dictionary of Measures of the Software Aspects of Dependability Sponsor Software Engineering Standards Committee of the IEEE Computer Society Approved 8 November 2005 IEEE-SA Standards Board Abstract: A standard dictionary of measures of the software aspects of depend
3、ability for assessing and predicting the reliability, maintainability, and availability of any software system; in particular, it applies to mission critical software systems. Keywords: availability, dependability, maintainability, reliability _ The Institute of Electrical and Electronics Engineers,
4、 Inc. 3 Park Avenue, New York, NY 10016-5997, USA Copyright 2006 by the Institute of Electrical and Electronics Engineers, Inc. All rights reserved. Published 8 May 2006. Printed in the United States of America. IEEE is a registered trademark in the U.S. Patent +1 978 750 8400. Permission to photoco
5、py portions of any individual standard for educational classroom use can also be obtained through the Copyright Clearance Center. Introduction This introduction is not part of IEEE Std 982.1-2005, IEEE Standard Dictionary of Measures of the Software Aspects of Dependability. Rationale for revision:
6、In accordance with Software Engineering Standards Committee (SESC) policy, the first standard (this document) is a small document with just a few core measures dealing with reliability, maintainability, and availability. This will be followed by a second standard that will address safety, confidenti
7、ally, and integrity. This standard has not been revised since 1988. It was reaffirmed in 1996, but there were significant negative comments. It has been revised because many of the original measures had the following undesirable characteristics: Unrealistic (i.e., there was naivety about the necessa
8、ry data, personnel capabilities, and training to effectively use the measures) Did not measure what they purported to measure Complex equations that were hard to understand and implement Immature (i.e., they were not widely used) Little field data to back up claims for benefits History This standard
9、 is 15 years old, and additional information on the topic has been developed since that time. This project updated the standard to include such information and to expand the scope of the standard. Specifically, the following topics were included in the standard: a) Determined specific criteria for i
10、nclusion of measures in the standard b) Performed a measure-by-measure review of the measures in the standard, with the following goals: 1) Determined whether the measure should be modified, retained, or deleted, based on the criteria. The modified and retained measures are identified in this standa
11、rd by their numbers from the original IEEE 982.1 standard (i.e., IEEE 982 #X). 2) Added any additional information on the measures developed since 1988. 3) Clarified definition and implementation conventions. 4) Identified and incorporated, where appropriate, new measures that have appeared since 19
12、88. 5) Formulated generic measure classes and categorized the measures into these classes. These classes are reliability, maintainability, and availability. iv Copyright 2006 IEEE. All rights reserved. Notice to users Errata Errata, if any, for this and all other standards can be accessed at the fol
13、lowing URL: http:/ standards.ieee.org/reading/ieee/updates/errata/index.html. Users are encouraged to check this URL for errata periodically. Interpretations Current interpretations can be accessed at the following URL: http:/standards.ieee.org/reading/ieee/interp/ index.html. Patents Attention is c
14、alled to the possibility that implementation of this standard may require use of subject matter covered by patent rights. By publication of this standard, no position is taken with respect to the existence or validity of any patent rights in connection therewith. The IEEE shall not be responsible fo
15、r identifying patents or patent applications for which a license may be required to implement an IEEE standard or for conducting inquiries into the legal validity or scope of those patents that are brought to its attention. Participants At the time this standard was completed, the P982 Working Group
16、 had the following membership: Allen Nikora, Chair Thomas Antczak William Everett William Farr Jairus Hihn J. Dennis Lawrence John Munson Norman Schneidewind George Stark Linda Wilbanks The following members of the individual balloting committee voted on this standard. Balloters may have voted for a
17、pproval, disapproval, or abstention. Richard Biehl Mitchell Bonnett Juris Borzovs Antonio M Cicu Rita Creel Geoffrey Darnton Einar Dragstedt Sourav Dutta John Emrich William Eventoff John Fendrich Yaacov Fenster Jon Hagar John Harauz Mark Henley John Horch William Junk Ron Kenett Thomas M. Kurihara
18、J. Dennis Lawrence Denis Meredith Rajesh Moorkath Lou Pinto Garry Roedler Terence Rout James Ruggieri Robert Schaaf Hans Schaefer Robert W Shillato Mitchell Smith Joyce Statz Udo Voges Paul Wolfgang Oren Yuen Janusz Zalewski Charles Zumbav Copyright 2006 IEEE. All rights reserved. When the IEEE-SA S
19、tandards Board approved this application guide on 8 November 2005, it had the following membership: Steve M. Mills, Chair Richard H. Hulett, Vice Chair Don Wright, Past Chair Judith Gorman, Secretary Mark D. Bowman Dennis B. Brophy Joseph Bruder Richard Cox Bob Davis Julian Forster* Joanna N. Guenin
20、 Mark S. Halpin Raymond Hapeman William B. Hopf Lowell G. Johnson Herman Koch Joseph L. Koepfinger* David J. Law Daleep C. Mohla Paul Nikolich T. W. Olsen Glenn Parsons Ronald C. Petersen Gary S. Robinson Frank Stone Malcolm V. Thaden Richard L. Townsend Joe D. Watson Howard L. Wolfman *Member Emeri
21、tus Also included are the following nonvoting IEEE-SA Standards Board liaisons: Satish K. Aggarwal, NRC Representative Richard DeBlasio, DOE Representative Alan H. Cookson, NIST Representative Don Messina IEEE Standards Project Editor vi Copyright 2006 IEEE. All rights reserved. vii Copyright 2006 I
22、EEE. All rights reserved. Contents 1. Overview 1 1.1 General 1 1.2 Scope . 2 1.3 Purpose 2 1.4 Compliance 2 1.5 Interaction with other standards. 3 2. Definitions 3 3. New reliability measures 4 3.1 General 4 3.2 Time to next failure (s) (Lyu B12) 4 3.3 Risk factor regression model (Schneidewind B22
23、).5 3.4 Remaining failures (Keller and Schneidewind B11). 6 3.5 Total test time to achieve specified remaining failures (Schneidewind B20) . 7 3.6 Network reliability (Schneidewind B19) 8 4. Modified reliability measures. 10 4.1 Defect density (982 #2) (Fenton and Pfleeger B5 and Nikora et al. B17)
24、10 4.2 Test coverage index (982 #5) (Binder B2) 11 4.3 Requirements compliance (982 #23) (Fischer and Walker B6) 11 4.4 Failure rate (982 #31) (Lyu B12) 12 5. Retained reliability measures 13 5.1 Fault density (982 #1) (Musa B14 and Nikora and Munson B16) . 13 5.2 Requirements traceability (982 #7)
25、(Fenton and Pfleeger B5) 15 5.3 Mean time to failure (MTTF) (982 #30) (Lyu B12 and Musa et al. B15) 16 6. New maintainability measures 17 6.1 Mean time to repair (MTTR) (Lyu B12 and Musa et al. B15) . 17 6.2 Network maintainability (Schneidewind B19)18 7. New availability measures 19 7.1 Availabilit
26、y (Lyu B12 and Musa et al. B15) 19 7.2 Network availability (Schneidewind B19) 20 viii Copyright 2006 IEEE. All rights reserved. Annex A (informative) Analysis of measures in IEEE Software Engineering Collection, IEEE Std 982.1-2006, Standard Dictionary of Measures to Produce Reliable Software 23 An
27、nex B (informative) Software Reliability Engineering Case Study (Keller and Schneidewind B11) 27 Annex C (informative) Glossary 32 Annex D (informative) Bibliography . 33 1 Copyright 2006 IEEE. All rights reserved. IEEE Standard Dictionary of Measures of the Software Aspects of Dependability 1. Over
28、view 1.1 General This standard has the following clauses: Clause 1 provides the scope of this standard. Clause 2 provides a set of definitions. Clause 3 through Clause 5 specify new, modified, and existing measures for reliability, respectively. Clause 6 and Clause 7 specify new measures for maintai
29、nability and availability, respectively. In addition, there are three informative annexes. Annex A documents the process that was used to determine whether a measure in the existing standard should be modified, retained, or deleted; this annex states the criteria that were used to determine whether
30、a measure should be included in the standard, including new measures. Annex B describes the Software Reliability Engineering Case Study, which provides a case study example of how to apply selected measures in Clause 3. Annex C is a glossary of terms taken from The Authoritative Dictionary of IEEE S
31、tandards Terms B8.1Annex D is a bibliography that provides additional information about measures in Clause 3 through Clause 7. Table 1 summarizes the categories of measures. Numerical applications of the measures can be found in the reference(s) that are keyed to each measure. 1The numbers in bracke
32、ts correspond to those of the bibliography in Annex D. IEEE Std 982.1-2005 IEEE Standard Dictionary of Measures of the Software Aspects of Dependability 2 Copyright 2006 IEEE. All rights reserved. Table 1 Summary of measures Identification Name Clause 3. New reliability measures 3.2 Time to next fai
33、lure (s) 3.3 Risk factor regression model 3.4 Remaining failures 3.5 Total test time to achieve specified remaining failures 3.6 Network reliability Clause 4. Modified reliability measures 4.1 Defect density (982 #2) 4.2 Test coverage index (982 #5) 4.3 Requirements compliance (982 #23) 4.4 Failure
34、rate (982 #31) Clause 5. Retained reliability measures 5.1 Fault density (982 #1) 5.2 Requirements traceability (982 #7) 5.3 Mean time to failure (MTTF) (982 #30) Clause 6. New maintainability measures 6.1 Mean time to repair 6.2 Network maintainability Clause 7. New availability measures 7.1 Availa
35、bility7.2 Network availability1.2 Scope This standard specifies and classifies measures of the software aspects of dependability. It is an expansion of the scope of the existing standard; the revision includes the following aspects of dependability: reliability, availability, and maintainability of
36、software. The applicability of this standard is any software system; in particular, it applies to mission critical systems, where high reliability, availability, and maintainability are of utmost importance. These systems include, but are not limited to, systems for military combat, space missions,
37、air traffic control, network operations, stock exchanges, automatic teller machines, and airline reservation systems. 1.3 Purpose This standard provides measures that are applicable for continual self-assessment and improvement of the software aspects of dependability. 1.4 Compliance An application
38、of the measures specified herein complies with this standard if Clause 2 through Clause 7 are implemented, with the exception of subclauses identified as either “Experience” and “Tools”. These subclauses are intended to (1) provide information about application domains for a given measure and (2) id
39、entify the types of tools appropriate for computing that measure. IEEE Std 982.1-2005 IEEE Standard Dictionary of Measures of the Software Aspects of Dependability 3 Copyright 2006 IEEE. All rights reserved. 1.5 Interaction with other standards The measures defined in this dictionary may provide inf
40、ormation that can help support certain evaluations discussed in other IEEE Software Engineering Standards. The following list is meant to be suggestive: IEEE/EIA Std 12207.0 Subclause 6.4.2 of IEEE/EIA Std 12207.0 lists verification tasks, and 6.5 lists validation tasks. Dependability measures may p
41、rovide useful quantitative information that will help satisfy these tasks. For example, in 6.4.2.5, one criterion states (among other requirements) that “the code implements correct data and control flow.”1IEEE Std 1074TMSubclause A.5.1 discusses evaluation activities, including reviews, traceabilit
42、y, testing, and reporting evaluation results. Dependability measures can provide useful quantitative information that can be used to assist these activities.2,3IEEE Std 1012TMThis standard lists verification and validation tasks, inputs, and outputs in Table 1. The dependability measures provided in
43、 this standard can provide useful quantitative information that can assist many of the tasks listed in this table. 2. Definitions For the purposes of this document, the following terms and definitions apply. The glossary in Annex C and The Authoritative Dictionary of IEEE Standards Terms B8 should b
44、e referenced for terms not defined in this clause. 2.1 defect: A generic term that can refer to either a fault (cause) or a failure (effect). (adapted from Lyu B12) 2.2 dependability: Trustworthiness of a computer system such that reliance can be justifiably placed on the service it delivers. Reliab
45、ility, availability, and maintainability are aspects of dependability. (adapted from Lyu B12) 2.3 maintainability: Speed and ease with which a program can be corrected or changed. (adapted from Musa B14) 2.4 measure (noun): (A) The number or symbol assigned to an entity by a mapping from the empiric
46、al world to the formal, relational world in order to characterize an attribute. (adapted from Fenton and Pfleeger B5) (B) The act or process of measuring. (adapted from Websters New Collegiate Dictionary B23) 2.5 measure (verb): To make a measurement. (adapted from Websters New Collegiate Dictionary
47、 B23) 2.6 time: In decreasing order of resolution, CPU execution time, elapsed time (i.e., wall clock time), or calendar time. (adapted from Musa B14) 1 EIA publications are available from Global Engineering Documents, 15 Inverness Way East, Englewood, CO 80112, USA (http:/ 2IEEE publications are av
48、ailable from the Institute of Electrical and Electronics Engineers, Inc., 445 Hoes Lane, Piscataway, NJ 08854, USA (http:/standards.ieee.org/). 3The IEEE standards or products referred to in this clause are trademarks of the Institute of Electrical and Electronics Engineers, Inc. IEEE Std 982.1-2005
49、 IEEE Standard Dictionary of Measures of the Software Aspects of Dependability 4 Copyright 2006 IEEE. All rights reserved. 3. New reliability measures 3.1 General The software reliability model specified in this clause (Schneidewind B20) is one of the four models recommended in ANSI R-013-1992 B1. See this reference for the other three recommended models that could be used in place of the specified model. 3.2 Time to next failure (s) (Lyu B12) 3.
