ISO/IEC/IEEE 24748-6:2023

INTERNATIONAL ISO/
STANDARD IEC/IEEE
24748-6
First edition
2023-07
Systems and software engineering —
Life cycle management —
Part 6:
System and software integration
Ingénierie des systèmes et du logiciel — Gestion du cycle de vie —
Partie 6: Intégration du système et du logiciel
Reference number
© ISO/IEC 2023
© IEEE 2023
© ISO/IEC 2023
© IEEE 2023
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Published in Switzerland
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Contents Page
Foreword .v
Introduction .vii
1 Scope . 1
2 Normative references . 1
3 Terms, definitions and abbreviated terms . 1
3.1 Terms and definitions . 1
3.2 Abbreviated terms . 3
4 Conformance . 3
4.1 Conformance to processes . 3
4.2 Conformance to information item content . 3
4.3 Full conformance . 3
4.4 Tailored conformance . 4
4.4.1 Processes . 4
4.4.2 Information items . . 4
5 Integration concepts . 4
5.1 General . 4
5.2 Interface concept . 4
5.3 Aggregation and synthesis concepts . 5
5.4 Integration concept . 5
5.5 Relationship of integration to life cycle processes . 6
5.6 Progressive interface definition . 7
5.7 Integration over the life cycle . 7
5.8 Iteration and recursion in integration . 8
5.8.1 General . 8
5.8.2 Iterative application of processes . 8
5.8.3 Recursive application of processes . 8
5.9 Regression testing in integration . 8
5.10 Integration enabling systems . 8
6 Integration process planning and application purposes . 9
6.1 General . 9
6.2 Integration planning and application guidelines . 9
6.2.1 General . 9
6.2.2 Integration strategy . 9
6.2.3 Efficiency considerations in the integration strategy . 10
6.2.4 Integration context. 11
6.2.5 Roles and competencies of integration team . 11
6.2.6 Methods used to perform integration .12
6.3 Integration process application requirements and guidelines . 20
6.3.1 General .20
6.3.2 Purpose . 20
6.3.3 Outcomes . 22
6.3.4 Activities and tasks .23
6.4 Other processes used in relationship to integration process application . 31
6.4.1 General . 31
6.4.2 Agreement processes . 31
6.4.3 Organizational project-enabling processes . 31
6.4.4 Technical management processes. 31
6.4.5 Technical processes . 32
6.5 Integration of systems-of-systems . 37
6.6 Integration throughout a system life cycle .38
7 Information item requirements .38
7.1 General .38
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7.2 Integration plan .38
Annex A (Informative) Coupling matrixes .40
Bibliography .42
IEEE notices and abstract .43
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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.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed
for the different types of ISO/IEC 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 or
www.iec.ch/members_experts/refdocs).
IEEE Standards documents are developed within the IEEE Societies and the Standards Coordinating
Committees of the IEEE Standards Association (IEEE-SA) Standards Board. The IEEE develops its
standards through a consensus development process, approved by the American National Standards
Institute, which brings together volunteers representing varied viewpoints and interests to achieve the
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While the IEEE administers the process and establishes rules to promote fairness in the consensus
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Attention is drawn to the possibility that some of the elements of this document may be the subject
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list of patent declarations received (see https://patents.iec.ch).
Any trade name used in this document is information given for the convenience of users and does not
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For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to
the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see
www.iso.org/iso/foreword.html. In the IEC, see www.iec.ch/understanding-standards.
ISO/IEC/IEEE 24748-6 was prepared by Joint Technical Committee ISO/IEC JTC 1, Information
technology, Subcommittee SC 7, Software and systems engineering, in cooperation with the Systems and
Software Engineering Standards Committee of the IEEE Computer Society, under the Partner Standards
Development Organization cooperation agreement between ISO and IEEE.
This first edition cancels and replaces ISO/IEC TS 24748-6:2016, which has been technically revised.
The main changes are as follows:
— changed from a Technical Specification to an International Standard;
— updated to reflect the process requirements of ISO/IEC/IEEE 12207:2017 and
ISO/IEC/IEEE 15288:2023;
— added material specific to software integration and systems-of-systems integration, as well as
system aggregation.
A list of all parts in the ISO/IEC/IEEE 24748 series can be found on the ISO and IEC website.
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Any feedback or questions on this document should be directed to the user’s national standards
body. A complete listing of these bodies can be found at www.iso.org/members.html and
www.iec.ch/national-committees.
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Introduction
Both ISO/IEC/IEEE 15288 and ISO/IEC/IEEE 12207 include an integration process that focuses
on aggregating the elements comprising a system. The integration process depends on a clear
understanding of interfaces of all kinds and the use, possibly repeated, of the verification process and
the validation process.
Systems that this document are concerned with are as described in ISO/IEC/IEEE 12207 and
ISO/IEC/IEEE 15288, i.e. systems that are human-made, comprised of any mixture of products and
services and can be configured with one or more of the following: hardware, software, data, humans,
processes (e.g. a review process or processes for providing service to users), procedures (e.g. operator
instructions), facilities, materials and naturally occurring entities (e.g. water, organisms, minerals).
The purpose of this document is to elaborate and facilitate the usage of the integration process given in
ISO/IEC/IEEE 12207 and ISO/IEC/IEEE 15288 by providing requirements and guidance for the planning
and performing of that process, including requirements for the information items to be provided for
systems and software integration, considering:
— the underlying concepts of aggregation, integration, interface, synthesis, verification, and validation;
— the possible composition of that human-made system;
— the life cycle stages of a system at which one or more parts of the integration process can occur;
— the context of the domain in which the system functions.
For life cycle process information items (documentation) described in ISO/IEC/IEEE 15288 and
ISO/IEC/IEEE 12207, ISO/IEC/IEEE 15289 summarises requirements for their content and provides
guidance on their development. Although this document identifies additional required information
items with related content for the integration process, it does not require a specific name, format,
recording media or explicit details for population of the information item's required content.
NOTE This document is intended to be consistent with the other parts of the ISO/IEC/IEEE 24748 series.
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INTERNATIONAL STANDARD ISO/IEC/IEEE 24748-6:2023(E)
Systems and software engineering — Life cycle
management —
Part 6:
System and software integration
1 Scope
This document:
— provides supplemental requirements and guidance for the planning and performing of the
integration processes given in ISO/IEC/IEEE 15288 and ISO/IEC/IEEE 12207;
— provides guidance on the relationship between the integration process and other life cycle processes.
— specifies requirements for information items to be produced as a result of using the integration
process, including the content of the information items.
This document is applicable to:
— those who use or plan to use ISO/IEC/IEEE 12207 or ISO/IEC/IEEE 15288, or both, on projects
dealing with human-made systems, software-intensive systems, and products and services related
to those systems, regardless of the project scope, methodology, size, or complexity;
— anyone planning or performing integration activities to aid in ensuring that the application of
the integration process and its relationships to other system life cycle processes conform to
ISO/IEC/IEEE 15288 or ISO/IEC/IEEE 12207.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO/IEC/IEEE 12207:2017, Systems and software engineering — Software life cycle processes
ISO/IEC/IEEE 15288:2023, Systems and software engineering — System life cycle processes
3 Terms, definitions and abbreviated terms
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/IEC/IEEE 15288,
ISO/IEC/IEEE 12207 and the following apply.
ISO, IEC and IEEE maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
— IEEE Standards Dictionary Online: available at: http:// dictionary .ieee .org
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NOTE For additional terms and definitions in the field of systems and software engineering, see
ISO/IEC/IEEE 24765, which is published periodically as a “snapshot” of the Systems and Software Engineering
Vocabulary (SEVOCAB) database and is publicly accessible at www .computer .org/ sevocab.
3.1.1
aggregate, noun
result of combining one or more physical, logical, or both, system elements
3.1.2
driver
launcher
external dynamic component or simulator that activates the performing of functions of an aggregate
(3.1.1) of system elements
3.1.3
interface
point at which two or more logical, physical, or both, system elements or software system elements
meet and act on or communicate with each other
3.1.4
integration
process of planning for and aggregating a progressively more complete set of physical, logical, or both,
system elements and activating their interfaces (3.1.3) to synthesize a system or part of a system whose
properties can be verified and possibly validated
Note 1 to entry: An outcome of integration is a system whose properties can be verified and possibly validated.
3.1.5
logical interface
input-output flow between two or more system elements or software system elements and the function
that determines it
Note 1 to entry: A logical interface can be functional (as in process steps), informational (as in a communications
link), or other.
3.1.6
physical interface
physical link between two or more system elements
Note 1 to entry: A physical interface can be solid, liquid, gas, vacuum, thermal, electromagnetic field, or other.
3.1.7
stub
computer programs and data files built to support software development and testing, but not intended
to be included in the final product
3.1.8
synthesis
result of combining the constituent elements of separate physical or logical, or both, entities into a
single or unified entity
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3.2 Abbreviated terms
API application program interface
ISC integration services components
MBSE model-based systems engineering
NDI non-developmental item
QA quality assurance
SDP software development plan
SEMP systems engineering management plan
SoI system-of-interest
4 Conformance
4.1 Conformance to processes
Conformance requirements for the integration process are specified in ISO/IEC/IEEE 12207:2017 and
ISO/IEC/IEEE 15288 and further elaborated in 6.3. One supplemental integration process outcome
is added in 6.3.3. If using ISO/IEC/IEEE 15288:2023 outcomes, it would become outcome h). If using
ISO/IEC/IEEE 12207:2017 outcomes, it would become outcome i).
4.2 Conformance to information item content
Clause 7 provides requirements for a number of information items to be produced during the life cycle
of a system.
A claim of conformance to the information item provisions of this document means that
— the required information items stated in this document are produced, and
— the information items produced demonstrate conformity to the content requirements defined in
this document.
Clause 7 contains the requirements for the content of the information items in this document.
In this document, each information item is described as if it were published as a separate document.
However, information items are considered to be conforming if the information items are unpublished
but available in a repository for reference, divided into separate documents or volumes, or combined
with other information items into one document. It is not required to treat every topic in this document
in the same order, using the same wording as its title, or with the same level of detail. That depends on
the nature of the system, implementation methods, life cycle model, and scope of the project.
4.3 Full conformance
A claim of full conformance to this document is equivalent to claiming conformance to the integration
process requirements identified in 4.1 and the requirements for the information items cited in 4.2.
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4.4 Tailored conformance
4.4.1 Processes
This document makes the following provision for a claim of tailored conformance to the integration
process: ISO/IEC/IEEE 12207:2017, Annex A and ISO/IEC/IEEE 15288:2023, Annex A provide
requirements regarding the tailoring of system and software life cycle processes. Those provisions
should be used to tailor the integration process requirements identified in 4.1 as the basis for a claim of
tailored conformance to the integration process as elaborated in this document.
4.4.2 Information items
When this document is used as a basis for establishing a set of information items that do not qualify for
full conformance, the requirements in Clause 7 are selected or modified in accordance with this clause.
The tailored text, for which tailored conformance is claimed, shall be declared. Tailored conformance is
achieved by demonstrating that requirements for the information items, as tailored, are satisfied.
5 Integration concepts
5.1 General
This clause presents the concepts that apply to system integration, including software systems. These
concepts embody the definitions in ISO/IEC/IEEE 12207 and ISO/IEC/IEEE 15288 and set the basis for
explaining the application of those concepts. The central concepts that this clause presents are those of
interface, aggregation, synthesis, and integration.
There are conceptual relationships between the integration process and system and software life cycle
processes of ISO/IEC/IEEE 15288 and ISO/IEC/IEEE 12207, which this clause presents. This clause also
presents the concepts associated with system integration as a process over the life cycle of a system,
including software systems.
Finally, this clause presents concepts on iteration and recursion in integration, and regression testing.
5.2 Interface concept
An interface has a set of logical or physical characteristics required to exist at a common boundary or
connection between system elements, systems, or the environment external to the SoI.
NOTE 1 Throughout this document, statements referring to "system elements" inferentially can include
elements of other systems, or the external environment.
A physical interface is a physical link that binds two or more system elements within the SoI, or one
system element of the SoI with one or more elements external to the SoI. A physical interface can be
considered a system element.
A logical interface consists of an output flow, or an input flow, or a bi-directional, i.e. transactional, flow
between two or more elements of the system so that the elements can exchange some mix of energy or
information items.
NOTE 2 Table 1 provides examples of system element integration involving physical interfaces (e.g. material
and thermal example of Table 1) and logical interfaces (e.g. the software-to-software example of Table 1).
The progressive definition of interfaces is an intrinsic part of applying the technical processes of
ISO/IEC/IEEE 12207 and ISO/IEC/IEEE 15288 and is critical to the success of integration. Inadequately
defined interfaces are common failure points in complex systems. Such inadequately defined interfaces
commonly include the points where independent systems or system elements not necessarily made
of the same technology meet and communicate with each other. Consideration for indirectly coupled
elements (e.g. via control mechanisms or shared memory in software systems) often involves complex
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analysis. Technical processes' activities and decisions should fully define interfaces so that integration,
and subsequent verification of system elements' properties, can be planned and performed successfully.
ISO/IEC/IEEE 12207:2017, E.5 and ISO/IEC/IEEE 24748-1:2018, D.5 provide a process view for the
management of interfaces and identify the purpose and outcomes with selected life cycle process
activities and tasks to facilitate the identification, definition, design, and management of interfaces of
the SoI.
5.3 Aggregation and synthesis concepts
The integration of a system is based on the notions of aggregation and synthesis. For example, wings,
body, engines, hardware and software controls, air traffic procedures, and information items, are
aggregated along with other elements not listed here to synthesize an aircraft operating in its intended
environment. A synthesis performs functions not possible from the individual elements that are
aggregated. An aggregate has a functional consistency that allows the performance of subsequent
verification actions and possibly validation actions. Each aggregate is characterized by a configuration
that specifies the implemented system or software elements that are aggregated and their configuration
status. Aggregation can be done iteratively or recursively.
5.4 Integration concept
Integration encompasses planning for and aggregating a progressively more complete set of elements
and activating their interfaces to synthesize a part of a system that can be verified and possibly
validated in keeping with strategy decisions for validation process implementation. Integration enables
interoperation among some set of elements to satisfy their requirements and provide a basis for
integrating a yet more complete part of the system. The end result is a system or software system that
is integrated within itself and at its interfaces for the system's intended purpose and use.
Integration of the system can involve a mix of the hardware, software, data, humans, processes (e.g.
processes for providing service to users), procedures (e.g. operator instructions), facilities, materials
and naturally occurring entities of which the system is composed. Hence, system integration can
involve interfacing and interoperating such things as mechanical items (e.g. assembly), functions (e.g.
software-based functions), people and equipment, thermal flows, sets of processes, human constructs
to naturally occurring entities.
NOTE 1 ISO/IEC/IEEE 15288:2023, 5.2.3 further explains concepts for interfacing systems and interoperating
systems.
A nuclear power facility is an example of a system that includes a mix of every type of elements
considered in ISO/IEC/IEEE 12207 and ISO/IEC/IEEE 15288 and involves both products and services.
Table 1 gives illustrative examples of the types of elements that are to be integrated for the system to
function properly in its operational environment over its life cycle. Table 1 illustrates the point that
verification is typically done following integration, depending on the verification strategy and priorities,
whereas validation can depend on factors other than successful confirmation that the interface has
been established and checked, and its properties verified.
Table 1 — Integration examples
System elements Types of interfaces Verification Validation follows?
being integrated involved follows?
Fuel and cladding to Material, thermal Yes Yes, but most likely done as part of validating
make reactor control the assembled reactor.
rods
Operator control panels Mechanical, electrical, Yes Most likely yes. Each type of control can be
functional, human-ma- verified individually, then some combination
chine interface, proce- of controls can be validated, that is, validation
dural can occur at a higher level in the system.
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TTaabbllee 11 ((ccoonnttiinnueuedd))
System elements Types of interfaces Verification Validation follows?
being integrated involved follows?
Reactor control and Software, human-machine Yes Most likely yes. Each type of control can be
monitoring operating interface, procedural verified individually, then some combination
system of controls can be validated, that is, validation
can occur at a higher level in the system.
Reactor rod control Software to software Yes No, but validated at a higher level, such as
software to flux densi- software to display
ty monitoring software
Facility server farm Hardware, software, data, Yes Probably, at several points
thermal, facilities, pro-
cesses
Reactor to cooling me- Naturally occurring entity, Yes Probably
dium, such as a lake or facility, thermal
river
Reactor generator to Hardware, functional Yes Yes
power grid
NOTE 2 Some of the integration results in products, some in services. In this example, electrical power to the
grid is a product of the reactor, while electrical power from the grid at the point of use is a service. Table 1 is
notional, for illustrative purposes only, and is not intended to be exhaustive.
NOTE 3 IEEE 1012 provides requirements and guidance for system, software, and hardware verification and
validation processes while the ISO/IEC/IEEE 29119 series provides detailed support for software testing.
Enabling systems are integrated, just as systems-of-interest, and an SoI and its enabling systems are
interfaced. If an SoI and its enabling system are interfaced the SoI and its enabling system can be
considered as a system-of-systems, or two systems, or as a new SoI, as a matter of perspective, per the
treatment in ISO/IEC/IEEE 15288 and ISO/IEC/IEEE 24748-1.
Integration can be considered successfully completed when all of the required interfaces are checked
and pass the required interface specifications for the integration step. Additional confirmation of the
successful completion of integration is when subsequent verification and possibly validation of the
interface properties is successful.
Planning and performing of integration is done in conjunction with other system or software life cycle
processes. Integration planning is mostly done in conjunction with requirements, architecture, design,
and test processes, while performing integration is mostly done in conjunction with verification and
validation processes.
A system can be integrated during a single stage, or involve multiple stages, of its life cycle and can be
integrated more than once within a single life cycle stage, such as when a system is repeatedly modified
during a lengthy stage of operation and maintenance, or when capabilities are added in discrete
increments.
5.5 Relationship of integration to life cycle processes
ISO/IEC/IEEE 15288 and ISO/IEC/IEEE 12207 recognize that any process can be invoked by any other
process and, conceptually, that applies to the integration process. In practice, the extent to which
integration is addressed when planning or performing other processes, as well as the extent to which
other processes are addressed when planning or performing the integration process, varies extensively.
Table 2 shows the relationship of some the other processes to the Integration process at a conceptual
level. Clause 6 addresses more specifics to consider as part of the integration planning or performing
guidelines.
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Table 2 — Conceptual relationship of integration to life cycle processes
ISO/IEC/IEEE 12207 and Relationship to integration pro- Relationship to integration process
ISO/IEC/IEEE 15288 process cess when planning integration when performing integration
groups
Agreement processes Agreements for system or software System or software elements obtained
elements obtained from a supplier, from a supplier are checked as spec-
or elements provided to a supplier, ified in the agreement before accept-
include requirements to be satisfied ance for integration with the SoI.
for integration that supports suc-
cessful verification, validation and
deployment. Agreement of interfaces
between supplier and customer.
Organizational project-enabling Provisions of the life cycle model Integration draws on the infrastruc-
processes management process, infrastruc- ture and provisions of the quality man-
ture management process, quality agement process. The lessons learned
management process, and knowl- from a specific integration effort are
edge management process include captured and made use of through the
capabilities for any interaction knowledge management process.
with the Integration process during
preparation, performing, or outcome
handling.
Technical management pro- Management of the intended integra- Management of the actual integration
cesses tion effort is reflected in the specific effort uses or provides input to each of
framework of each of these process- these processes.
es: integration uses or provides input
to each of these processes.
Technical processes Integration concepts, requirements, Implementation, verification, tran-
and solutions emerge from the busi- sition, validation, operation, mainte-
ness or mission analysis, systems nance, and disposal processes all draw
requirements, architecture defini- on or are supported by the integration
tion, and design definition process- process over the life cycle of the sys-
es, drawing on the system analysis tem.
process
NOTE The relationships in Table 2 also apply to enabling systems.
5.6 Progressive interface definition
Interfaces are progressively defined, with the first descriptions at a high level commonly occurring
with application of the business or mission analysis process, then throughout the application of the
requirements, architecture and design processes. The integration process coordinates with those
processes to check that the interface definitions, as implemented and integrated, are adequate and that
the processes consider the integration needs.
5.7 Integration over the life cycle
Life cycle concepts and models, as discussed in ISO/IEC/IEEE 24748-1 and ISO/IEC/IEEE 24748-3, relate
directly to the integration process in two ways.
a) Integration planning should be done with a consideration of the system's or software system’s
entire life cycle, or remaining life cycle, in mind. There can be a need to integrate some part of the
system's elements at any stage of the life cycle.
NOTE 1 For example, integration in the concept stage can be done on conceptual models.
b) Integration can also be done at any stage of a system's life cycle.
NOTE 2 In particular, system modifications to extend or improve utilization and support often drive a
requirement to integrate the changed parts of the software or system.
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A system’s complexity can impact integration planning and stage planning. A system can have any
mix of products and services and be composed of one or more of the following: hardware, software,
data, humans, processes (e.g. processes for providing service to users), procedures (e.g. operator
instructions), facilities, materials and naturally occurring entities. Since those various products and
services can have different life cycle models, the timing and outputs associated with each model should
support integration of the overall system at all affected stages of the system's life cycle.
5.8 Iteration and recursion in integration
5.8.1 General
Two forms of process application – iterative and recursive – are useful for applying the Integration
process. Iteration and recursion concepts are provided in ISO/IEC/IEEE 12207 and ISO/IEC/IEEE 15288
and explained in detail in ISO/IEC/IEEE 24748-1.
This discussion on iterative and recursive use of system or software life cycle processes is not meant to
imply any specific hierarchical, vertical, or horizontal structure for the SoI or enabling system.
5.8.2 Iterative application of processes
When the application of the same process or set of processes is repeated on the same system, the
application is referred to as iterative.
The integration process is used iteratively starting from a first aggregate of system elements, which
can include software unit or software item configurations for software system elements, until the
completion of the SoI. The last successful iteration of the integration process results in the entirely
integrated SoI.
The verification process is used with the integration process to perform the planned verification
procedures related to the integration iteration.
The validation process can be used iteratively when performing the planned validation procedures
related to a set of integration and verification actions.
5.8.3 Recursive application of processes
When the same set of processes or the same set of process activities are applied to successive levels of
system elements within the system structure, the application method is referred to as recursive.
The integration process is used by any system-of-interest at any level of the decomposition of the
system, hence can be used recursively.
The verification and validation processes can be applied following, as part of, or in conjunction with,
the integration process in each recursion.
5.9 Regression testing in integration
It is often necessary to re-run tests previously completed on a lesser set of a system's elements. Element
interfaces or simulated equivalents remain available for regression testing to be feasible. These
considerations can be carried over to ensuing life cycle stages.
5.10 Integration enabling systems
The purpose of an integration enabling system is to provide an environment that serves to prepare for
and perform the integration of any SoI for one or more life cycle stages. It can be viewed as a facility
including the necessary services, and the resources and tools for integration. Each integration enabling
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system is a system in its own right, in which its life cycle activities interact with those for the SoI to
enable successful integration of the SoI.
NOTE 1 The enabling system is defined in ISO/IEC/IEEE 12207 and ISO/IEC/IEEE 15288 and can apply in the
case of integration. An integration enabling system has its own life cycle composed of generic stages and uses the
system or software processes of ISO/IEC/IEEE 12207 and ISO/IEC/IEEE 15288, but is instantiated for each SoI to
be integrated.
NOTE 2 For a given SoI, the composition of the enabling system can be different at different life cycle stages,
considering the particular composition of system elements that are being integrated at that stage.
NOTE 3 Other independent enabling systems can exist for verification, validation and delivery purposes, or be
combined with the integration enabling system.
ISO/IEC/IEEE 15288:2023, Annex D discusses system life cycle process implementation using an
approach applicable for both MBSE and model-based systems and software engineering. When using
this approach, early model and method selection and potential compatibility issues for integration are
important planning considerations. The timing and content of the outputs of models (e.g. UML/SysML
diagrams, 3D models) and simulations (e.g. electrical loads, material flow) that enable the realization of
a system should be integrated among themselves and any activities to integrate the system itself.
NOTE 4 ISO/IEC/IEEE 24641 specifies a reference framework for systems and software engineering with a
model-based approach
6 Integration process planning and application purposes
6.1 General
This clause presents guidelines for planning and applying the integration process stated in
ISO/IEC/IEEE 15288 and ISO/IEC/IEEE 1220
...