Service and System thinking
Department of Computer Systems and Communications
Academic Year: 2016-2017
Francesco Caputo
fcaputo@mail.muni.cz
Key concepts of Systems Thinking
• What is systems thinking?
• Why do ‘systems thinkers’ get
promoted?
• How does the field of information
systems benefit from concepts of
systems theory?
• How can we use these concepts in the
real world?
Contemplative Questions
◦ A system is an interrelated set of business procedures used within one
business unit working together for a purpose
◦ A system has nine characteristics
◦ A system exists within an environment
◦ A boundary separates a system from its environment
Systems Thinking
◦ Components
◦ Interrelated Components
◦ Boundary
◦ Purpose
◦ Environment
◦ Interfaces
◦ Input
◦ Output
◦ Constraints
Characteristics of a System
Characteristics of a System
◦ The process of breaking down a system into smaller components
◦ Allows the systems analyst to:
◦ Break a system into small, manageable subsystems
◦ Focus on one area at a time
◦ Concentrate on component pertinent to one group of users
◦ Build different components at independent times
Important System Concepts
Modularity
◦ Process of dividing a system into modules of a relatively uniform size
◦ Modules simplify system design
Coupling
◦ Subsystems that are dependent upon each other are coupled
Cohesion
◦ Extent to which a subsystem performs a single function
Which is better:
More or less modularity?
High or low coupling?
High or low cohesion?
Important System Concepts
◦ Logical System Description
◦ Portrays the purpose and
function of the system
◦ Does not tie the description to a
specific physical
implementation
◦ Physical System Description
◦ Focuses on how the system will
be materially constructed
Logical vs. Physical Modeling
◦ Identification of a system leads to
abstraction
◦ From abstraction you can think about
essential characteristics of specific
system
◦ Abstraction allows analyst to gain
insights into specific system, to
question assumptions, provide
documentation and manipulate the
system without disrupting the real
situation
Benefits
◦ Information systems are subsystems in larger organizational systems
◦ Data flow diagrams represent information systems as systems
◦ Inputs
◦ Outputs
◦ System boundaries
◦ Environment
◦ Subsystems
◦ Interrelationships
Applying Systems Thinking to Information Systems
Questions ???