1. Complexity of the Systems Integration
Sergey Tozik, Gordon Center for Systems Engineering, Technion
http://www.gordon-se.technion.ac.il/
Summary
Systems Integration is one of the important stages of the life cycle of any man-made system.During this
stage, realized instances of the system's components are combined to create a complete system. Despite
widespread recognition that during the Integration the discovery of the problems is most
frequent, this phase in the lifecycle has not received much attention in comparison with other
stages such as Requirement Elicitation or System Architecture. The research that does deal with the
Integration focuses primarily on the planning processes and optimization, or on case studies that describe
the development of the integration facilities.
This paper uses the information gathered during the meetings of Systems Integration Working Group
organized by the Israeli chapter of INCOSE (INCOSE_IL) as well as several papers that are published on
the subject to gain an insight into the peculiarities of the Systems Integration.
As may be expected, companies and organizations use a variety of engineering and managerial techniques
and approaches to perform integration during the projects and other activities. The mere existence of such
variety points that there cannot be found "the winning method" of Systems Integration but rather that
there is a "toolbox" of methods and techniques. The effectiveness and efficiency of application of these
techniques are highly dependent on their suitability to both the nature of the products and projects of each
organization and the culture prevailing in these organizations.
Systems Integration is a complex process. This complexity emerges from the interdependencies between
the components inside the system, between the components and their developers, and most of all between
the multitude of people involved in the development and integration of the system, everyone with her own
experience, training, engineering disciplines and the technologies. More than that, there is never-ending
mutual adaptation of the evolving system, the supporting organization, the users and their organizational
processes.
The Integration happens on multiple levels of hierarchy. Essentially, three types of integration may be
discerned - the Product Integration that focuses on the integration of the artificial elements of the system
and of the system with other artificial systems, the Human Integration that is focused on the mutual
adaptation of the system and its ultimate users and the Operational Integration that is focused on the
incorporation of the system (and its users) into the fabric of the operational processes in the acquiring
organization and beyond it.
Research community offers many solutions for dealing with the complexity of the systems,and the
processes of the development and integration. But this community focuses elsewhere and doesn't look too
deep into the human side of the "integration business" and doing so leaves much room for new interesting
research. Adaptability of people may certainly be the "missing ingredient" in the coping with the
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2. complexities of the development projects especially during the integration, in the attempts to reduce the
complexity of the project in its last stages and thus reduce costs, shorten development time and increase
the likelihood that the system will succeed in the complex operational environment.
Introduction
Despite widespread recognition that during the Integration the discovery of the problems is most frequent,
this phase in the lifecycle has not received much attention in comparison with other stages such as
Requirement Elicitation or System Architecture. The research that does deal with the Integration focuses
primarily on the planning processes and optimization, or on case studies that describe the development of
the integration facilities.
Deep interest in Systems Integration in the community of the practitioners led to the establishment of
Systems Integration Working group by the Israeli chapter of INCOSE (INCOSE_IL) with the
representation of various companies and organization in both commercial and government sector. As part
of the Work Group activities the representatives of several organizations presented their Systems
Integration processes and techniques, among them Rafael, the Israel Electric Company, ECI, Motorola,
Phillips Healthcare, Biosense Webster, Orbotech, Israeli Air Force, HP and others. The presentations and
discussions revealed a lot of information about how the Systems Integration process is actually performed
in these organizations.
This paper uses the information gathered during the meetings of Systems Integration Working Group
organized by the Israeli chapter of INCOSE (INCOSE_IL) as well as relevant publications to gain an
insight into the peculiarities of the Systems Integration and point out promising research topics.
Characteristics of the integration process
In one of the meetings, the Work Group endeavored to list activities that are relevant to the Systems
Integration. As expected, in the center of the Integration stand engineering activities of preparing and
performing the integration testing events - writing integration plans, establishing integration facilities,
development of the tools including the tools for modeling and simulation, conducting the tests and writing
the reports. In addition it became clear that the implementation of the integration process requires other
activities as well that are as important to the success of the whole process.
Organization of integration events requires considerable logistical support including acquisition,
transportation and installation of the system's components and supporting equipment, configuration
management of both integration laboratories and the interim configurations of the system, establishing an
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3. infrastructure of communication between the participants and transportation of people between the
different integration sites.
Management of the integration process includes planning, measurement of the progress, preparation for
design and managements reviews, organization of integration and test readiness reviews, establishing of
the integration teams, management of these teams including encouragement and appreciation of the team
members.
The integration process is a resource-intensive process but not always perceived as such during project
planning stages. Part of the responsibilities of the integration leader is to secure and manage the
resources, including the preparation of budgets, justification of need for resources, fighting for
preservation of the allocation of resources and also reporting on resource utilization.
During the integration process there exist quite a few activities identified with the systems engineering
including analysis of the changes in the needs and demands of stakeholders that take place during the
project, systems analysis, and problems investigation, design of remedial actions and system's
improvements and the management of their implementation.
The integration process is characterized by the flow of information and knowledge among the project
participants, sometimes the increased information flow during integration compensates for the inadequate
information exchange and documentation at the earlier stages of the project. Accordingly, the integrators
must manage the flow of knowledge and information within and without the project and to manage
information flow to the various stakeholders, including the use of techniques borrowed from the public
relations.
Variety of processes and approaches
As more members of the Work Group presented their integration processes in their companies, it became
apparent that there is a very wide variety of integration processes used by different companies and there
are even differences between the different divisions of the same company. In some companies (especially
in the defense sector) there are highly structured processes and procedures to perform the integration that
even serve as a "skeleton" for planning the entire project not just the integration stages. In other
companies the integration processes were tailored separately for each project and in other companies the
integration "just happened" in pure ad-hoc fashion. The variety of the integration processes was as large
as the variety of systems engineering processes in particular and organizational cultures in general.
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4. Overall consensus was reached that the process of integration starts early in the project (when there are at
least two components to integrate) and finishes very late in the project (when the product are transferred
to the customers and even far beyond the project end, during production and support).
As the participants presented their technical approaches to design and execution of the integration, the
wide variety emerged as well. The systems were integrated functionally, hierarchically, by user-visible
features, by the leading engineering disciplines (software, physical, mechanical, electrical, electronic etc)
or by user types.
Although in most companies, the concept of internal and external is the element that defines the approach
to integration (and expressed in formal interface specifications) some of the companies didn't emphasize
interfaces but rather used terms like "fitting components to each other", without documenting specific pair
wise interfaces but rather documenting the overall design that shows how the components "fit together".
Diversity of approaches to integration also includes a variety of approaches to organizing the teams
involved in the integration. Although the topic of organizing integration teams was not the focus of the of
companies' presentations, but during the discussions it became clear that there is a range of options for
teams structure starting with the organic integration teams, through task teams led by systems engineers,
to the ad-hoc integration team consisting of representatives of various development teams without an
official manager (integration was led by the representative from the team which has more responsibility
for the success of the integration event).
In the companies that emphasized the need for the professionalism in the integration by organizaing
dedicated integration departments, these departments may be assigned additional responsibility for the
customer support, field engineering or detailed design of the interfaces. On the one hand the above
responsibilities are not usually identified with the systems integration and on the other hand this is a sign
that there is a strong association between these areas and the systems integration.
From the aforementioned findings one can assume that the quality, the effectiveness and the efficiency of
the integration process do not depend on the choice of the universal best practices on the amalgam of the
approaches and adapted to the type of products and organizational culture in the company. There may
well be a "toolbox" of methods and approaches to choose from but not the "best-of-breed" comprehensive
methodology.
Systems Integration as part of Risk Management
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5. There is an inherent difference between the activities of System Integration and those of Systems Design.
During the integration the physical artifacts are interconnected to form larger assemblies, whether in
design one works primarily with information artifacts and abstractions. The interaction between real-
world artifacts is always richer than what are predicted using abstract descriptions or models. During the
integration the unexpected assembly-level properties and behaviors gradually emerge. These behaviors
may still appear exhibited in the final configuration of the system or many disappear or change. The latter
"false attributes" may further complicate the integration process but can't be avoided due to
incompleteness of the integration configurations and the low fidelity of the representation of the operating
environment.
Gerrit Muller states in his (Muller 2007) that "The goal of integration is to reduce the project risk of being
late or the risk of creating an ill performing system". He argues that the integration plays a major role in
risk reduction because the integrators are focused on finding unforeseen problems and solve them as early
as possible.
There is no way to avoid integration challenges - in course of building any sufficiently complicated
system there is always aomebody that has to assume responsibility for the proper functioning of the
systems and for solving the problems during the assembly, installation, transition to use and the actual
operation. Couper, Emes and Smith (Couper et al 2005) point out that when no one consciously accepts
the responsibility for integration, the responsibility will by default be assigned to the end users or on the
engineers that represent the users making them "by-default Systems Integrators". These "by-default
Systems Integrators" will bear the risk that the system will be inadequate for the operational use either
due to exhibition of unacceptable emergent properties, or due to change in user's needs, or due to low
reliability.
Most projects reach the stage of integration both with depleted resources and with a host of unsolved
proplems .Since during the integration the actual physical configurations are assembled and activated for
the first time, it's impossible to deny those problems and the need to solve them becomes more tangible
for the development team, and what is more important, to the management and for the customers.
According to the article (Sheard 2000) by Sarah A. Sheard the Systems Engineer has to perform the role
she called "the Glue" - the role of active problem seeker and solver. She didn't use the term "Systems
Integrator" in order to prevent the confusion with the "Lead Systems Integrator" definition used in the
contracts.
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6. She emphasized that the Systems Engineer in her "Glue" role has to be "proactive troubleshooter, looking
for the problems and arranging to prevent them". She emphasizes that the designers of the subsystems are
focused on making "their subsystems do what they are supposed to do, while the systems integrator has to
focus on the interfaces and the interrelationships between the subsystems, looking for the mutual
interference.
Three levels of system integration complexity
Systems Integration is a complex process. It is not apparent when one considers only the integration
between artificial components of the system, so I would like to distinguish between three levels of
Systems Integration - Artifact or Product Integration, System Integration and Operational Integration.
In the course of the Artifact Integration the artificial components of the system is brought together to form
partial configurations, the interfaces are mated and the configurations are stimulated to elecitate
responses. The actual responses are judged against the expected ones documented as system's
requirements. Artifact Integration is probably what most engineers imagine when they think about
systems integration. For most purposes the Systems Integration and the Artefact Integration are
considered synonymous.
Most systems cannot function by themselves without the interaction with humans. In most cases, the
operators or users are considered a part of the system's environment integration with the machines
through human-machine interfaces that are treated as external. On the other hand in order to put the
machines to use, the users and the machines has to adapt to each other. This mutual adaptation is the
second level of the Systems Integration - the Human-Machine Integration. Humans are not components
that may be produced according to specifications (even when one talks about training) and therefore free
to change their behavior depending on personal preferences, accumulated experience in operating similar
systems and a gradual adaptation to the new system they work with. People are complex creatures and
their integration with the artificial components of the system raises the level of the complexity that are not
considered during the Artifact Integration.
Still another level of integration increases the complexity even more - the Operational Integration. During
the Operational Integration the artificial systems and its users are integrated into the their organization's
business or operational processes and into the "enterprise ecosystem". Operational Integration is seldom
identified as Systems Integration but those that are involved in putting the systems into operational use
may testify that this process has many characteristics of integration. In the light of the above one could
consider the Operational Integration as the third and the most complex level of Systems Integration.
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7. When looking at the integration process in the various organizations it can be seen that the organizations
that represent the ultimate users focus more on Operational Integration and the companies that are
suppliers of systems focus more on Artifacts Integration. The Human-Machine Integration is frequently
under-emphasized and is allocated to be a part of the training. There are also companies that create a
partnership with clients and take responsibility for all three levels of integration, bridging the gaps
between them. It's interesting thet the companies involved in all three levels of integration have more
influence on customers' requirements specification and thus have more control of the costs and profits.
The human side of the systemic integration
Much of the complexity in the integration process is due to interactions between people that participate in
this process. According to the opinion of the Working Group participants the Systems Integration is
characterized by intense social dynamics, that emerges from the encounters (sometimes for the first time)
between the representatives of the different development teams thas has worked fairly independently on
the system components right until the start of the integration. Despite the importance of human aspect to
the success of the integration process it is not getting much attention in the publications or discourse
between the practitioners who rather prefer to focus on the engineering and managerial side of their work.
One can find references to the human aspect of the integration edge in the papers that deal with other
aspects of the integration, such as the article by Scott A. Hyer (Hyer, 1997) that writes:
"When defining integration, the human side must also be considered. The development of any
complex system involves many specialists and at least a few coordinators (managers and systems
engineers) ... The activity's principle drivers are communication among the development team
members and advance planning ... The only way to achieve this is through effective
communication which comes from strong leadership and coordination ...
Thus, at a very basic level, integration can be viewed from at least two perspectives: (1) as a
technical challenge to system designers and (2) as a team coordination activity to managers. It
must be a distributed effort which influences every project team member but, at the same time,
remains centrally monitored and controlled. Simply stated, this is the challenge "
Not only communication and cooperation between the people is important to the success of integration,
but also the ways of each person that participates in the process. In his article (Ring 2007) on the subject
of "intelligent enterprises" Jack Ring states that the need for "interpersonal integration derives from the
inherent limitations of the human mind:
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8. "... People are the key ingredient, A minimum of two are required because the single brain
cannot discriminate illusion from reality.
Each person in or associated with the enterprise has a mental model of a) purpose and intended
outcomes, b) what behaviors are and are not acceptable and c) ways their enterprise can pursue
purpose. In the intelligent enterprise, these mental models are coherent. In the intelligent
enterprise with a high mode of intelligence, the mental models reinforce and amplify one
another. Likewise, each person has a sufficient level of enthusiasm to help one another overcome
fear, ideally transforming that energy into more enthusiasm thus innovation. "
Summary
Systems Integration is a complex process. Complexity of the integration process is greater than that of the
Systems Design of the development of system components and that for a number of reasons: when
implemented, the components and their interactions are more complex than any description or
specification, the systems are used by people that adapt to the systems they operate, the changes in the
operational processes that the use of the new systems triggers. The complexity of the integration process
makes it a major source of risks in projects, with significant impact on the schedule, costs and
performance of the systems.
Research community offers many solutions for dealing with the complexity of the systems, the
development and integration processes. On the other hand this community does not focus on the impact of
the human side of the integration on its success and thus leaves much room for new research on this topic.
Adaptability of people may certainly be the "missing ingredient" in the coping with the complexities of
the development projects especially during the integration, in the attempts to reduce the complexity of the
project in its last stages and thus reduce costs, shorten time and increase the likelihood that the system
will succeed in the complex operational environment.
Control of complexity may be based on regulation of diversity by implementation of standards and
procedures or by giving "free rein" to the creative integration teams, by regulation of adaptation by
training of the users and the preparation of the business environment to the absorption of new systems and
by regulation of interdependence by controlling the flow of information and knowledge between the
participants by means of facilitating or even prevention or disruption of communication.
Sources:
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9. Cowper, D., Emes, M. and Smith, A, "... is en in Heaven or in hell is en That Illusive Systems
Integrator - Who's Looking After Your Systems Integration", INCOSE Publication Database (
Https://www.incose.org/ipub/ ), 2005
Hyer, Scott, A, "An Effective Approach To System Integration: A Comprehensive Checklist",
INCOSE Publication Database, 1997
Muller, Gerrit, "Coping with System Integration Challenges in Large Complex Environment",
INCOSE Publication Database), 2007
Ring, Jack, "About Intelligent Enterprises: A Collection of Knowledge Claims", INCOSE
Technical Document, INCOSE-TD-2007-001-01, 2007
Sheard, Sarah A., "Twelve Systems Engineering Roles", INCOSE Publication Database, 1996
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