Project Life cycle

Software development life cycle

Before we look at Project life cycle let us first look at the Software Development Life Cycle (SDLC), which we are already familiar with. This is a structure/ process imposed on the development of a software product. There are several models available for such process, each having its own pros and cons and it is up to the development team to chose the process that would best suit their Project, Product or Environment.

For Ex Waterfall , Agile , Scrum are different SDLC methods , each one suitable for different project types.

A typical Waterfall development method will have the following phases in the Software development in the specified order.

   1. Requirements specification (Requirements analysis)
   2. Software Design
   3. Integration
   4. Testing (or Validation)
   5. Deployment (or Installation)
   6. Maintenance
In a strict Waterfall model, the developers move to the Next Phase only when the Previous phase is fully complete and exit criteria is met.

SDLC represents the work of creating the software system.

Project Life Cycle

If SDLC talks on the work of creating the software system, the Project Life cycle represents the process used to Manage the SDLC. That include the Initiation, Planning, Execution, Monitoring and control.

SDLC vs PLC

SDLC and PLC are almost interlinked and overlap themselves. Refer the attached figure, to get an idea .

For Ex. In the Planning phase of the PLC,  if it was decided that the project will use a waterfall method, the interaction can be depicted as show in Fig2.1, 

All the SDLC phases from requirements gathering till Implementation will go in the Execution phase. Here I have assumed that we are doing a Full project. In some cases, the project itself could be only to do "Analysis" and if so this "analysis" phase of SDLC will be in the Execution phase of PLC


Similarly, there is a interaction of the PLC to each SDLC Phase. For Example assume your project has completed system testing and you have decided to proceed to the next phase i.e. User Acceptance Testing.

UAT phase may be carried with the following activities

1)Call a UAT startup meeting with stake holders. Discuss any key, important points from system/performance testing that was done before. Discuss in brief on the process to follow during UAT . (INITIATION)
2)Revisit or Create a plan for UAT. This could include who will test what, preparation of test cases, where to log defects, how to notify development team for Critical show stoppers, response time from development team etc (PLANNING)
3)Do the actual testing as per the UAT plan (EXECUTION)
4)Conduct review meeting and take actions as appropriate (MONITOR & CONTROL)
5)Finally implement the project. (Well, the product can also be rejected and may be we start all over from design or development) and close the phase (CLOSE).

So, you can clearly see that SDLC and PLC are very much interlinked and often overlap among and between themselves.

The Fig2.3 also shows that PLC phases overlap with each other and a typical resource requirement during the different phases.


PLC phases need not necessarily start only after completion of the prior phase. They are very much overlapping and Iterative as well.