Systems Development – Basic concepts

 

Learning Outcomes:

• Describe the phases involved in systems development using the Waterfall Model.
• By using suitable case studies, students should experience the processes and activities involved in various phases of systems development.
• Explore the limitations and shortcomings of the Waterfall Model.
• Recognise the benefits and limitations of other approaches.
• Other approaches include Prototyping and Rapid Application Development (RAD).

 

Waterfall Model

 

Steps:

1. System requirement Analysis: Compile user requirements. Document: Requirement documentation.
2. System Design: Establish software and hardware requirements.
3. Implementation: implement the design. Program coding is written.
4. Testing and Integration: Look for any errors in the coding. All units are integrated.
5. Deployment: Deployed to users.
6. Maintenance: Further updates if issues arise.

Each phase is completed before going to the next one.

Documentation is integrated into all the phases.

 

Relevant past paper:

DSE ICT Elect B(SP-2017):  SP 4a. 2013 3b. 2016 1ai-iii.

AL CS2(2003-2012): 2007 1a. 2008 3. 2010 3a,bii,c. 2012 2, 8a.

Learn more: AL CS2 2004 13ab.

  

Limitations and shortcomings of the Waterfall Model

 

The model goes forward only and does not support going backward for revision or improvement.

Requirements defined in the initial phases. Cannot accommodate requirement changes.

Development time is usually longer than other approaches. (no overlapping of different phases)

 

Prototyping

 

After knowing the basic requirement, a prototype of the system is built. Users can try the system and provide feedback to refine the system requirements.

 

Rapid Application Development (RAD)

 

Uses prototyping approach.

Aim at quick development while reducing cost and maintaining quality.

 

Drawback:

• require active user involvement
• RAD not applicable if the system cannot be modularized
• need highly skilled developers for modelling

 

Relevant past paper:

DSE ICT Elect B(SP-2017):  SP 4b. 2014 1aiv. 2016 1aiv.

AL CS2(2003-2012): 2007 1b. 2010 8f. 2012 8b.

 

References:

https://www.tutorialspoint.com/sdlc/sdlc_waterfall_model.htm

http://tryqa.com/what-is-prototype-model-advantages-disadvantages-and-when-to-use-it/

http://cisaexamstudy.com/prototype-rapid-application-development-rad-point-remember/

https://marutitech.com/rapid-application-development/#Disadvantages_Of_Rapid_Application_Development