WBS-WORK-BREAKDOWN-STRUCTURE
What is it?
• An exhaustive and objective list of things-to-do, in a simple case.
• For a complex project/task, it is a hierarchical (tree) structure,
whose terminal nodes show all atomic work-units to meet the
project deliverables.
• Giv es a clear and complete picture of the scope of work.
Why do we need it?
• Understanding the work-units comprising the total project work is
a minimum requirement for successful completion of a project.
• Needed for developing the Activity Network model, which is an
important project planning and management tool:
− allocate resources (time + personnel) and create a schedule.
− monitor work-progress to meet milestones and the project
deadline, and taking corrective actions as needed.
WBS: Comes after the requirements are defined.
• Identifies all activities (work-units) that the product-developer
will carry out to deliver the final product.
• Helps to create the project-plan.
− Activity definitions: What things are to be done.
− Activity sequencing: When to do what (logical precedences).
− Activity resource allocation (cost/time estimation): Who will
do what and when.
− Activity scheduling: Actual time-line for activities.
− Schedule control: Who will be responsible for what
Role Of Breakdown
• Suggests the possibility that the cars can perhaps be repaired one
at a time instead of multiple cars being repaired in parallel.
• It does not say the order in which the cars are to be repaired.
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Work-Unit: A terminal node of the tree-hierarchy.
• One person responsible for each work-unit’s proper completion.
Top-Down Approach:
• Best way to identify the work-units is by the top-down and
breadth-first (level by lev el).
Question:
•? What would be a possible breakdown
A POOR WBS
Work-units vs. Deliverables:
• They are not the same.
• Project deliverables are part of project requirements, and workunits are part of WBS.
Example of Poor WBS:
• Does not identify the work-units to meet the deliverables.
WHAT’S IN A WBS TREE
Features of WBS-tree (Completeness = 100% rule):
• Higher level nodes tend to be "work-types" or "work-categories"
(hence common to many WBS’s).
• The terminal nodes, also called work-units, are more project specific. They together represent the actual total work to be done
(100% rule), and account for all internal and external deliverables, and all input (material/data) uses and outputs created.
• Each intermediate node is just a larger conceptual "chunk of
work", the children (≥ 2) give a breakdown to smaller chunks.
• A work-unit is a small enough chunk that is measurable (can estimate resources - time, personnel, costs - needed to complete it).
• The intermediate nodes help to identify the terminal nodes.
http://www.csc.lsu.edu/~kundu/soft-engg/workBreakdown/wbs.pdf
