Waterfall

Waterfall

1. Waterfall method

   • Traditional software development method that follow a set of steps in a specific order
   • When using this approach...
     • Programmers move from stage to stage in sequence unless problems are encountered.
       • If problem are encountered or alterations to an earlier stage need to be made...
         • The programmer needs to repeat subsequent stages.

2. Iteration

   • Repeat
   • programmer who follow waterfall method
     • will repeat stages like design, implementation and testing fairly regularly.
     • Why iterate?
       • New information
         • Such as ?
           • Test table with incorrect results
   • Happens between stages
     • Example
       • Repeating design and implementation after finding errors in testing.
   • Happen within stages
     • Example
       • using dry run to change code during implementation
       • Re-interviewing a end user during analysis
     • Implementation
       • Provide the most obvious phase of the process for iteration within a stage
       • Programmers will often revise code as they are constructing the program
         • By the use of breakpoints or by conducting dry runs.
   • Revisiting a previous stage in light of new information from a subsequent stage
   • The traditional analysis stage
     • involves a system analyst meeting with the client and taking part in a interview
       • The interview is designed to allow the analyst to get an idea of what the client needs from the new software
         • The interview is often needed to repeat the interview process several times.