BUILDING A WBS : • WBS is the key work product needed to do software project to selection as a framework for estimating. There is atop-down & a bottom up approach to building any WBS. WBS constructing a five steps. They are • Identify the work concerning the software product. • Find any higher system WBS. • Determine the software WBS architecture. • Populate the software WBS architecture. • Determine cost categories for software.
APPROACHES TO BUILDING A WBS: • A WBS can be organized in many ways . Its usually best to arrange the activities around major work products & customers requirements. The hierarchical “tree” of information is • The compiler. • The basic parts of the compiler • The steps of the development process to build the basic parts of the compiler
WBS branches directly correlated to deliverable to be produced. organizing a WBS around deliverable and the action to produce those deliverables helps keep unnecessary work from being done on the project. • WBS around the projects deliverables and work produt is good way to avoid planning extra work into the project. Several possible arrangements for WBS. • The basic element of the project. • Other element could also be used ,such as deliverables, skills, responsibilities . • WBS have include hardware , software & business process.
The WBS can be created from top down and bottom up approaches . • Top down approach involves successive decomposition. • Bottom up approach uses brain storming & affinity diagramming. The big components of work that will need to be done and to make Rough Order of Magnitude (ROM). It is based on Broad Rule of thumb.
Top down approaches: • Its involves starting with the top most item and breaking it down from there , getting progressively more granular at each level. • It work that can reasonably done by “one unit of resource” in a relatively “short period time” have reached
Bottom up approach: • It is good fit for a new type of project, when the project team is not very familiar with the steps that would be performed. • Its during the project and then grouping the activities into level of granularity and arranging all the activities into ever higher grouping until the top level item is reached.