System is a purposeful collection of interrelated components that work together to achieve some objective.
a) technical computer-based systems - only hardware + software, e.g. word processor
b) socio-technical systems - include technical systems + people + processes; in organization; non deterministic; e.g. publishing system for books
Emergent(całościowe) system properties:
a) functional emergent properties - e.g. bicycle has the functional property of being a transportation device
b) non-functional emergent properties - e.g. reliability, performance, safety and security
the system success or failure is depending on these properties
Systems engineering
- activity of specifying, designing, implementing, validating, deploying and maintaining socio-technical systems; system engineers must take into account the software, hardware, people and the environment; the must think about the services the system provides, the constrains under which it must be built;
system engineering process != software development process
System engineering process includes:
a) specification
b) design
c) development
d) integration --> critical if sub-systems come from more then one supplier
e) testing
Legacy system - old socio-technical system that still provides essential business services.
