Question

WHAT IS A SYSTEM DEVELOPMENT LIFE CYCLE? WHAT ARE SOME OF THE PREDICTIVE MODELS ASSOCIATED WITH THE SYSTEMS DEVELOPMENT LIFE CYCLE

Answer 1

System Development Life Cycle (SDLC) is a conceptual model that includes policies and procedures for developing or altering systems throughout their life cycles.

SDLC is used by analysts to develop an information system. SDLC includes the following activities −

• requirements
• design
• implementation
• testing
• deployment
• operations
• maintenance

PREDICTIVE MODELS

Waterfall Model
Well-defined & linear stages of systems development and support
Assumes that requirements will remain stable after they are defined
Uses: when risk must be tightly controlled and when changes must be restricted after requirements are defined
Used in many large-scale projects where complexity and cost are high

Spiral Model
Recognizes that most software is developed using an iterative or spiral approach rather than a linear approach
The project team is open to changes and revisions later in the cycle
Uses: for projects in which changes can be incorporated with reasonable cost increases or acceptable time delays

Incremental Build
Provides for the progressive development of operational software, with each release providing added capabilities
Uses: by organizations that issue a specific release of a software package while working on future revisions that will be distributed later in another release with a higher "build" or version number
Helps stage the priorities of a package's features and functions with user priorities

Prototyping Model
Used for developing software prototypes to clarify user requirements for operational software
Requires heavy user involvement and developers use a model to generate functional requirements and physical design specifications simultaneously
Uses: in systems that involve a great deal of user interface design, that automate previously manual functions or that change the nature of how something is done

Rapid Application Development (RAD) Model
Uses an approach in which developers work with an evolving prototype
Requires heavy user involvement and helps produce systems quickly without sacrificing quality
Uses RAD tools
CASE (computer-aided software engineering)
JRP (joint requirements planning)
JAD (joint application design)
Uses: in reporting systems in which programmers enter parameters into the software to generate user approval.