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Systems Development Life Cycle

Referred to variously as the waterfall model and linear cycle, this methodology is a coherent description of the steps taken in the development of information systems. The reason why it is referred to as the waterfall model should be obvious from the following figure (from Horner, 1993):

 
Figure:   Systems Development Life Cycle

The methodology SDLC is closely linked to what has come to be known as structured systems analysis & design. It involves a series of steps to be undertaken in the development of information systems as follows:

The figure below provides an illustration for the above description.

 
Figure:   Dataflow Diagram for SDLC

The waterfall model has many attractive features: Clearly defined deliverables at the end of each phase, so that the client can take decisions on continuing the project. Incremental resource committment. The client does not have to make a full committment on the project at the beginning. Isolation of the problem early in the process.

It does, however, have some drawbacks:

Requires an all-or-nothing approach to systems development. Does not allow incremental development. Requires very early isolation of the problem. In the real world, often the problems are uncovered in the process of development of systems.



next up previous contents
Next: References Up: Methodologies for Systems Previous: Methodologies for Systems



Jagdish Gangolly
Fri Sep 8 20:22:25 EDT 2000