Different Testing activities in Design phase

The design document aids in programming, communication, and error analysis and test data generation. The requirements statement and the design document should together give the problem and the organization of the solution i.e.what the program will do and how it will be done.
The design document should contain:
- Principal data structures.
- Functions, algorithms, heuristics or special techniques used for processing.
- The program organization, how it will be modularized and categorized into external and internal interfaces.
- Any additional information.

The testing activities should consist of:
- Analysis of design to check its completeness and consistency
The total process should be analysed to determine that no steps or special cases have been overlooked. Internal interfaces, I/O handling and data structures should specially be checked for inconsistencies.

- Analysis of design to check whether it satisfies the requirements
Check whether both requirements and design documents contain the same form, format, units used for input and output and also that all the functions listed in the requirement document have been included in the design document. Selected test data which is generated during the requirement analysis phase should be manually simulated to determine whether the design will yield the expected values.

- Generation of test data based on the design
The tests generated should cover the structure as well as the internal functions of the design like the data structures, algorithm, functions, heuristics and general program structure etc. Standard extreme and special values should be included and expected output should be recorded in the test data.

- Re-examination and refinement of the test data set generated at the requirements analysis phase.

The first two steps should also be performed by some colleague and not only by the designer or developer.

Synchronize and stabilize lifecycle model

The synchronize and stabilize lifecycle model defines an overall approach for developing and managing large-scale software systems.
Synchronize-and-stabilize (also called sync-and-stabilize) is a Systems Development Life Cycle methodology in which teams work concurrently on individual application modules. They frequently synchronize their code with that of other teams, and debug or “stabilize” their code regularly throughout the development process.
The special feature of this model is that the specification are complete only when the product is ready. This model has been used extensively by many innovative product development organizations.

Advantages of Synchronize-and-stabilize model

- The periodic system building approach paves way for testing the software for both functionality and performance.
- Project monitoring will be easy as there are intermediate milestones.
- The integration problems encountered in large projects using other models are eliminated in this model.
- Because of intermediate releases, the product can be made feature rich by incorporating the necessary feedback.

Disadvantages of Synchronize-and-stabilize model

- A parallel independent testing team needs to be in place.
- The detailed specifications document will be made available only at time of release.
- Periodic system builds require a rigorous process to be defined for integration of various modules.

Evolutionary Development Model - A software development life cycle model

The waterfall model is viable for software products that do not change very much once they are specified. But for software products that have their feature sets redefined during development because of user feedback and other factors, the traditional waterfall model is no longer appropriate.
- The Evolutionary EVO development model divides the development cycle into smaller, incremental waterfall models in which users are able to get access to the
product at the end of each cycle.
- Feedback is provided by the users on the product for the planning stage of the next cycle and the development team responds, often by changing the product, plans, or process.
- These incremental cycles are typically two to four weeks in duration and continue until the product is shipped.

Benefits of Evolutionary Development Model

- Benefit not only business results but marketing and internal operations as well.
- Use of EVO brings significant reduction in risk for software projects.
- EVO can reduce costs by providing a structured, disciplined avenue for experimentation.
- EVO allows the marketing department access to early deliveries, facilitating development of documentation and demonstrations.
- Short, frequent EVO cycles have some distinct advantages for internal processes and people considerations.
- The cooperation and flexibility required by EVO of each developer results in greater teamwork.
- Better fit the product to user needs and market requirements.
- Manage project risk with definition of early cycle content.
- Uncover key issues early and focus attention appropriately.
- Increase the opportunity to hit market windows.
- Accelerate sales cycles with early customer exposure.
- Increase management visibility of project progress.
- Increase product team productivity and motivation.