Friday, October 28, 2011

Testing Software Requirement Specification

Most of the bugs in software are due to incomplete or inaccurate functional requirements?” The software code, doesn’t matter how well it’s written, can’t do anything if there are ambiguities in requirements.It’s better to catch the requirement ambiguities and fix them in early development life cycle. Cost of fixing the bug after completion of development or product release is too high.  So it’s important to have requirement analysis and catch these incorrect requirements before design specifications and project implementation phases of SDLC.
we need to define some standard tests to measure the requirements. Once each requirement is passed through these tests you can evaluate and freeze the functional requirements.
Client (stakeholders) specified the project requirements for initial phase of the project development. Once manager circulated all the requirements in the team for review. When the discussion was started on these requirements. Everyone was having their own conception about the requirements. We found lot of ambiguities in the ‘terms’ specified in requirement documents, which later on sent to client for review/clarification.
Client used many ambiguous terms, which were having many different meanings, making it difficult to analyze the exact meaning. The next version of the requirement doc from client was clear enough to freeze for design phase.
Next criteria for testing the requirements specification is “Discover missing requirements”
Many times project designers don’t get clear idea about specific modules and they simply assume some requirements while design phase. Any requirement should not be based on assumptions. Requirements should be complete, covering each and every aspect of the system under development.
Specifications should state both type of requirements i.e. what system should do and what should not.
When one  read the software requirements specification document (SRS), they should  note down their own understanding of the requirements that are specified, plus other requirements SRS document should supposed to cover. This helps me to ask the questions about unspecified requirements making it clearer.
For checking the requirements completeness, divide requirements in three sections, ‘Must implement’ requirements, requirements those are not specified but are ‘assumed’ and third type is ‘imagination’ type of requirements. Check if all type of requirements is addressed before software design phase.
Check if the requirements are related to the project goal.
Sometimes stakeholders have their own expertise, which they expect to come in system under development. They don’t think if that requirement is relevant to project in hand. Make sure to identify such requirements. Try to avoid the irrelevant requirements in first phase of the project development cycle. If not possible ask the questions to stakeholders: why one  want to implement this specific requirement? This will describe the particular requirement in detail making it easier for designing the system considering the future scope.
How to decide the requirements are relevant or not?
Set the project goal and ask this question: If not implementing this requirement will cause any problem achieving our specified goal? If not, then this is irrelevant requirement. Ask the stakeholders if they really want to implement these types of requirements.
In short requirements specification (SRS) doc should address following:
Project functionality (What should be done and what should not)
Software, Hardware interfaces and user interface
System Correctness, Security and performance criteria
Implementation issues (risks) if any
Requirements should be clear and specific with no uncertainty, requirements should be measurable in terms of specific values, requirements should be testable having some evaluation criteria for each requirement, and requirements should be complete, without any contradictions”
Testing should start at requirement phase to avoid further requirement related bugs. Communicate more and more with your stakeholder to clarify all the requirements before starting project design and implementation.

1 comment:

  1. Software testers will It is also test up to and beyond the bounds defined in the software requirements specification. STC Technologies|STC Technologies