Bi-directional product development process simulation

• US 20060101383A1
• Filed: 06/16/2005
• Published: 05/11/2006
• Est. Priority Date: 06/17/2004
• Status: Active Grant

• Current Assignee: State Of Oregon Acting By And Through The State Board Of Higher Education On Behalf Of Portland State University
• Original Assignee: German University, Oregon State University (Oregon University System)
• Inventors: Raffo, David M.
• Granted Patent: US 7,793,271 B2
• Time in Patent Office: Days
• US Class Current: 717/104
• CPC Class Codes: G06F 8/20 Software design
• CPC Class Codes: G06Q 10/06 Resources, workflows, human or project management; Enterprise or organisation planning; Enterprise or organisation modelling

Abstract

A bi-directional software development process simulation model is described. The model simulates the stages of a software development process, taking advantage of equations relating to defect injection and detection along with parameters describing detection and injection rates. By simulating the development process in the forward direction, predictions can be made for process outcomes. By simulating in the reverse direction, defect detection requirements can be found for each stage of the model to achieve a given desired performance result. Outcome-based control levels are utilized with the model in order to better detect whether a process is out of control and should be corrected. By going between the forward and reverse simulation directions, control of the process can be fine-tuned as defect detection data is obtained during process execution. In addition to quality as measured by defects, other metrics can be simulated, including cost, time, and features; similarly other product development scenarios, such as hardware or systems engineering can also be modeled and simulated.

Claims

1. A method of simulating a software development process through analysis of a quality metric, the method comprising:

selecting a reverse software development process simulation model corresponding to the software development process, the model comprising a plurality of development stages;

determining defect parameters for the plurality of stages of the reverse software development process simulation model;

determining reverse defect equations for the plurality of stages of the reverse software development process simulation model;

determining outcome-based control statistics for the software process; and

applying the reverse defect equations to the outcome-based control statistics and the defect parameters to determine control requirements for the plurality of stages of the reverse software development process simulation model.

2. The method of claim 1, further comprising:

selecting a forward software development process simulation model corresponding to the software development process, the model comprising a plurality of development stages, each of the plurality of forward stages corresponding to one of the plurality of stages of the reverse software development process simulation model;

determining forward defect equations for the plurality of stages of the forward software development process simulation model;

applying the forward defect equations to the defect parameters to determine baseline process performance data; and

comparing the process performance data to the outcome-based control statistics to determine if the software development process is out of control.

3. The method of claim 2, further comprising:

determining that the software development process is out of control; and

analyzing control requirements for the plurality of stages of the reverse software development process simulation model to identify one or more stages which will improve the process performance data determined from the forward software development process simulation model when the defect parameters for the one or more identified stages are improved.

4. The method of claim 3, further comprising:

modifying one or more defect parameters; and

applying the forward defect equations to the modified defect parameters to determine modified process performance data; and

comparing the modified process performance data to the baseline process performance data to determine how the software development process has been improved.

5. The method of claim 2, wherein determining reverse defect equations comprises modifying the forward defect equations to create reverse defect equations.

6. The method of claim 2, wherein selecting a reverse software development process simulation model comprises modifying the selected forward software development process simulation model to create a reverse software development process simulation model.

7. The method of claim 2, wherein the defect parameters include defect injection rates and the reverse and forward software process development simulation models are configured to accept defect injection rate parameters.

8. The method of claim 7, wherein the defect parameters include inspection effectiveness and test effectiveness and the forward and reverse software process development simulation models are configured to accept inspection effectiveness and test effectiveness parameters.

9. The method of claim 8, wherein each of the plurality of stages of the forward software development process simulation model produces performance data representing the number of defects which have escaped detection or correction at that stage.

10. The method of claim 9, wherein the baseline performance data is produced by the last stage of the forward software process development simulation model.

11. The method of claim 8, wherein each of the plurality of stages of the reverse software development process simulation model accepts a maximum number of defects to be allowed after the simulation of that stage and produces a maximum number of defects that could be accepted before simulation of the stage as a defect requirement for that stage.

12. The method of claim 1, wherein the reverse software development process simulation model comprises a waterfall process model, a rational unified process model, or conforms to an IEEE 12207 process design standard.

13. The method of claim 1, wherein the selected reverse software process development simulation model and forward software process development simulation model comprise generalized software process simulation models.

14. A method for controlling a software development process through analysis of cost, quality, or schedule metrics, the method comprising:

determining outcome-based control limits for the software development process for a cost, quality, or schedule metric;

selecting a bi-directional software process development simulation model with corresponds to the software development process, the bi-directional simulation model comprising a plurality of development stages along with forward and reverse simulation equations;

determining baseline parameters for the software process development simulation model;

determining a baseline performance prediction by simulating the software development process using the software process development simulation model;

comparing the baseline performance prediction to the outcome-based control limits to determine if the software development process is in control using the baseline parameters;

determining parameter requirements for each stage of the bi-directional software process simulation model based on the outcome-based control limits;

analyzing the parameter requirements to determine one or more stages whose parameters, when improved, will improve a performance prediction from the bi-directional software development process simulation model; and

modifying one or more parameters.

15. A system for planning and controlling a software development process, the system comprising:

simulation software configured to display simulation models, to allow editing of process simulation models, to execute process simulations, and to report simulation performance results;

a bi-directional software development process simulation model comprising a plurality of software development stages and forward and reverse defect equations, the model configured to accept defect parameters and produce simulation performance data measured in defects and to accept outcome-based control limits and produce defect requirements; and

a data and parameter repository containing defect parameters and configured to receive simulation performance results.

16. A computer-readable medium containing data which, when read by a computer, describe a bi-directional software development process simulation model configured to accept defect parameters and produce simulation performance data measured by quality and to accept outcome-based control limits for quality and produce defect requirements.

17. The computer-readable medium of claim 16, where the bi-directional software development process model comprises:

a plurality of stages; and

forward and reverse defect equations representing interactions between each of the plurality of stages; and

wherein the bi-directional software development process simulation model is configured to accept defect parameters and produce simulation performance data measured by quality and to accept outcome-based control limits for quality and produce defect requirements.

18. A method of controlling a software development process through analysis of cost, quality, or schedule metrics, the method comprising:

analyzing the software development process to create outcome-based control limits for one or more selected metrics, the limits representing acceptable levels for the one or more metrics at the outcome of the software development process;

creating a bi-directional software development process simulation model, the model comprising;

a plurality of development stages configured to represent the stages of the software development process;

baseline simulation parameters for the one or more selected metrics; and

forward and reverse simulation equations configured to accept metric parameters and produce predictive simulation data for the one or more selected metrics;

performing a baseline simulation of the software development process using the baseline simulation parameters and the bi-directional model to obtain baseline predictive performance data;

performing a portion of the software development process to obtain updated development data;

performing an updated simulation of the software development process using the updated development data and the bi-directional model to obtain updated predictive performance data;

performing a reverse simulation of the software development process using the updated development data to determine stages where performance benefits can be achieved; and

revising the software development process to achieve performance benefits.

19. The method of claim 18, wherein the bi-directional model further comprises a data repository which is configured to accept simulation parameters and simulation data.

20. The method of claim 18, wherein predictive simulation data comprises predictive performance data and requirements data.

21. The method of claim 18, wherein performing a reverse simulation comprises utilizing the reverse simulation equations and updated data to develop requirements data for each process stage that has not been performed.

22. The method of claim 18, further comprising determining that the updated development data is outside of control limits.