A system to process, collect, store and produce result to fulfil business needs
Software/application and information system might be used interchangeably but they are not the same entity.
Software is a subset of an information system, an information system consists of software, hardware, storage, people components.
Information system is built for people’s need to solve problem, opportunity and/or directive
Motivation to have an information system
The jargon is Initiation in SDLC definition
Problem – events that hinders the functionality of an organization.
Opportunity – Although there is no problem with the current system, but people have the desire to improve the system
Directive – requirements, orders, policies by higher executives, managers, directors or government
(personal comment: usually it is really hard to get budget for a new project motivated by opportunity, sometime it was approved but the process was arduous. However if the project was initiated by a directive, approval could be as fast as immediate; (as good as rubber stamping without even looking at the official proposal)initially there could be budget constraint suddenly an influx of budget would be teleported magically!)
System development life cycle
Initiation – The trigger or motivation to build an information system
Planning – Outsourcing for people to do the work, seeking quotation from vendors, plan for budget
Analysis – Identify the problem, seeking client’s requirement, finding out the stakeholders
(In a nutshell analysis sought to understand a system’s requirement to solve the current problem, to fulfil future opportunities, to comply with directives)
Design – Based on requirements gathered from Analysis, sought for a solution to piece components together to form a system
Construction – To build an information system based on design specification
Implementation – Testing the built system, coaching operation stakeholders to work on the new system. System goes live, stakeholders start to use the system.
Support – Maintenance, patching softwares of the information system, improve on security, resiliency and performance
(Personal comment: AS the information system gets older and more stakeholders use this system, the performance naturally deteriorates, this system will be used until it is end of support by external providers or there is no possibility of improving the resiliency and performance anymore which triggers the cycle from initiation again…)
Detailed definition of SDLC
Reference: System Analysis and design in a changing world by John Satzinger, Robert Jackson and Stephen Burd, page 7, Chapter 2 From Beginning to End: An Overview of Systems Analysis and Design.
Initiation – Identifying the problem and obtain specification
(Personal comment: This should be initiation and analysis together)
Plan – Plan and monitor the project
(Personal comment: Monitor the project should be from start of design until implementation.)
Analysis – Discover and understand the details
(Personal comment: How do you get the specification when you have not discovered and understood the details?)
Design – Design system components
Construction – Build, test and integrate the system
Implementation – Complete system tests and deploy the solution