ISO/IEC 14143-6:2012

INTERNATIONAL ISO/IEC
STANDARD 14143-6
Second edition
2012-11-01
Information technology — Software
measurement — Functional size
measurement
Part 6:
Guide for use of ISO/IEC 14143 series and
related International Standards
Technologies de l'information — Mesurage du logiciel — Mesurage de
la taille fonctionnelle
Partie 6: Guide pour l'usage de la série ISO/CEI 14143 et des Normes
internationales connexes
Reference number
©
ISO/IEC 2012
©  ISO/IEC 2012
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
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ii © ISO/IEC 2012 – All rights reserved

Contents Page
Foreword . iv
Introduction . v
1  Scope . 1
2  Abbreviated terms . 1
3  FSM related standards (ISO/IEC 14143 series), FSMM standards, and their
interrelationships . 2
3.1  Outlines of FSM related standards . 2
3.2  Outlines of standardized FSMMs . 4
3.3  Relationship between FSM related standards . 6
3.4  Guidelines for usage of FSM related standards . 8
4  Use of FSM and FS . 8
4.1  Overview . 8
4.2  Project management . 9
4.3  Performance management . 10
5  FSMM selection and development processes . 10
5.1  Outline . 10
5.2  Process to select a suitable FSMM . 11
5.3  FSMM development process . 13
Annex A (Informative) Scope of FSM related standards . 15
A.1  ISO/IEC 14143 series . 15
A.2  ISO/IEC International Standards of FSMMs . 17
Bibliography . 21

© ISO/IEC 2012 – All rights reserved iii

Foreword
ISO (the International Organization for Standardization) and IEC (the International Electrotechnical
Commission) form the specialized system for worldwide standardization. National bodies that are members of
ISO or IEC participate in the development of International Standards through technical committees
established by the respective organization to deal with particular fields of technical activity. ISO and IEC
technical committees collaborate in fields of mutual interest. Other international organizations, governmental
and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information
technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of the joint technical committee is to prepare International Standards. Draft International
Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
an International Standard requires approval by at least 75 % of the national bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this part of document may be the subject of
patent rights. ISO and IEC shall not be held responsible for identifying any or all such patent rights.
ISO/IEC 14143-6 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology,
Subcommittee SC 7, Software and systems engineering.
ISO/IEC 14143 consists of the following parts, under the general title Information technology — Software
measurement — Functional size measurement:
— Part 1: Definition of concepts
— Part 2: Conformity evaluation of software size measurement methods to ISO/IEC 14143-1
— Part 3: Verification of functional size measurement methods [Technical Report]
— Part 4: Reference model [Technical Report]
— Part 5: Determination of functional domains for use with functional size measurement [Technical Report]
— Part 6: Guide for use of ISO/IEC 14143 series and related International Standards
This second edition cancels and replaces the first edition (ISO/IEC 14143-6:2006), which has been technically
revised.
iv © ISO/IEC 2012 – All rights reserved

Introduction
Functional Size Measurement (FSM) is a technique used to measure size of software by quantifying the
Functional User Requirements of the software. The first published method to embrace this concept was
Function Point Analysis, developed by Allan J. Albrecht in the late 1970s. Since then, numerous extensions
and variations of the original method have been developed. In the field of ISO/IEC International Standards, the
following Functional Size Measurement-related International Standards and Technical Reports have been
published:
— ISO/IEC 14143 series, parts 1 to 5,
— ISO/IEC 19761 (COSMIC method),
— ISO/IEC 20926 (IFPUG method)
— ISO/IEC 20968 (Mk II method),
— ISO/IEC 24570 (NESMA method), and
— ISO/IEC 29881 (FiSMA method).
This part of ISO/IEC 14143 was established to provide FSM Method users and developers with a guide as to
how these International Standards and Technical Reports relate to each other and how to use them.
The Functional Size (FS) obtained by measuring a piece of software, contributes to a better understanding of
the characteristics of the software as well as the development, maintenance and support activities thereof.
The three types of International Standards and Technical Reports related to the definition and use of FS
and/or Functional Size Measurement (FSM) are:
a) Concept Standards: Describe concepts and provide definitions,
b) Supporting Standards: Supply information to assist in the evaluation of Functional Size Measurement
Methods (FSMM) and examples of the software domains that they measure, and
c) Method Standards: Define instances of FSMMs.
Any FSMM, other than the Method Standards, can be used to measure FS as long as it conforms to
ISO/IEC 14143-1. FSMMs can vary in their capability to measure software in different domains. Therefore,
before deciding on which FSMM to use, it is advisable to assess the capability of the method to adequately
size the software to be measured.
This part of ISO/IEC 14143 provides guidance on how to select a suitable FSMM using all FSM-related
standards.
The FS results obtained from applying the selected FSMM can be used for a variety of purposes throughout
the lifecycle of the software. This part of ISO/IEC 14143 also provides illustrative examples of how to use FSM
and functional size to manage aspects of software development and maintenance.

© ISO/IEC 2012 – All rights reserved v

INTERNATIONAL STANDARD ISO/IEC 14143-6:2012(E)

Information technology — Software measurement — Functional
size measurement
Part 6:
Guide for use of ISO/IEC 14143 series and related International
Standards
1 Scope
This part of ISO/IEC 14143 provides a summary of the FSM-related standards and the relationship between;
a) the ISO/IEC 14143 series FSM framework International Standards that provide the definitions and
concepts of FSM, and conformity and verification of FSMMs, and
b) the ISO/IEC standard FSMMs, i.e. ISO/IEC 19761, ISO/IEC 20926, ISO/IEC 20968, ISO/IEC 24570 and
ISO/IEC 29881.
This part of ISO/IEC 14143 also provides a process to assist users to select and develop an FSMM that meets
their requirements as well as providing guidance on how to use FS. FSMMs include, but are not limited to,
ISO/IEC 19761, ISO/IEC 20926, ISO/IEC 20968, ISO/IEC 24570 and ISO/IEC 29881.
NOTE An FSMM is a software sizing method that conforms to the mandatory requirements of ISO/IEC 14143-1.
Recommending a specific FSMM is outside the scope of this part of ISO/IEC 14143.
The audiences of this part of ISO/IEC 14143 are:
 users and potential users of FSM; and
 developers of an FSMM.
2 Abbreviated terms
BFC Base Functional Component
FS Functional Size
FSM Functional Size Measurement
FSMM Functional Size Measurement Method
FUR Functional User Requirements
RUR Reference User Requirements
© ISO/IEC 2012 – All rights reserved 1

3 FSM related standards (ISO/IEC 14143 series), FSMM standards, and their
interrelationships
3.1 Outlines of FSM related standards
3.1.1 Overview
FSM is an approach used to measure software size by quantifying the FUR of the software. Over time
numerous methods have been devised to do this of which five of them conform to ISO/IEC 14143-1 became
the International Standards. Although these methods vary in the rules they use to measure software, they all
focus on measuring FUR of software.
ISO/IEC 14143-1 defines concepts of FSM and FSMM. Subsequent parts of ISO/IEC 14143 (ISO/IEC 14143
series) have been developed to evaluate FSMMs.
The following clauses outline these FSM related standards.
NOTE For copies of the Scope clauses of the FSM related standards, refer to Annex A of this part of ISO/IEC 14143.
3.1.2 ISO/IEC 14143-1
ISO/IEC 14143-1 is a Concept Standard and is a basis for other International Standards and Technical
Reports that are categorized as Supporting Standards and Method Standards.
ISO/IEC 14143-1 is the foundation standard of the series and has the following contents;
a) Definitions
b) Characteristics of FSMMs
c) Requirements for FSMMs
d) Process for applying an FSMM
e) FSMM labeling conventions
f) Conformity evidence
ISO/IEC 14143-1 is an International Standard.
3.1.3 ISO/IEC 14143-2
ISO/IEC 14143-2 is a Supporting Standard.
ISO/IEC 14143-2 defines processes to check conformity of a Candidate FSMM with ISO/IEC 14143-1.
NOTE While conformity can be assessed in another method, using ISO/IEC 14143-2 is recommended.
ISO/IEC 14143-2 has the following contents;
a) Evaluator characteristics
b) Inputs to conformity evaluation
c) Tasks and steps of the conformity evaluation procedure
d) Conformity evaluation outputs
2 © ISO/IEC 2012 – All rights reserved

e) Conformity evaluation result
In addition, there are the following annexes;
a) Evaluator capability (Informative)
b) Example of a conformity evaluation checklist (Informative)
c) Example of a conformity evaluation report (Informative)
ISO/IEC 14143-2 is an International Standard.
3.1.4 ISO/IEC TR 14143-3
ISO/IEC TR 14143-3 is a Supporting Standard.
For FSMM users wanting to evaluate the most suitable method for their needs or for developers who want to
check their FSMM performance claims, ISO/IEC TR 14143-3 provides a process to assess the performance
properties of an FSMM. While there are many ways to do the verification, the use of ISO/IEC TR 14143-3 is
recommended.
ISO/IEC TR 14143-3 has the following contents;
a) Verification team competency and responsibility
b) Verification inputs
c) Verification procedure
d) Verification outputs
In addition, it includes the following annexes;
a) Presentation of test requests (Normative)
b) Verification methods (Normative)
c) Example of a verification report (Informative)
ISO/IEC TR 14143-3 is a Type 2 Technical Report.
3.1.5 ISO/IEC TR 14143-4
ISO/IEC TR 14143-4 is a Supporting Standard.
ISO/IEC TR 14143-4 provides a collection of Reference User Requirements (RUR), which are useful for
comparing the FSM results among FSMMs. It also contains guidance on selecting Reference FSMMs.
Together with ISO/IEC TR 14143-3, it enables the collection of normative, quantitative evidence of the
performance of the FSMM.
ISO/IEC TR 14143-4 has the following requirements;
a) Reference User Requirements
b) Reference FSMMs
In addition, it includes the following example Reference User Requirements in annexes;
a) Business application RUR (Normative)
© ISO/IEC 2012 – All rights reserved 3

b) Real time / Control RUR (Normative)
c) RUR reference list (Informative)
ISO/IEC TR 14143-4 is a Type 2 Technical Report.
3.1.6 ISO/IEC TR 14143-5
ISO/IEC TR 14143-5 is a Supporting Standard.
...