This article is devoted to the consideration of Software Requirements Specifications, their importance in the software development process, and how they could be written. Within this article, I will pay more attention to the effective SRS template and its description.
- What is an SRS template?
- What does this document consist of?
- What should be considered when writing a successful SRS?
I will try to give the answers to all these questions and other questions regarding Software Requirement Specifications.
Overview
Software Requirements Specifications is a document that contains written representation, generally for developers, about how the software system should be developed.
This document has a quite significant role. The fact is that a programmer may not fully understand a particular subject area. For example, a client wants an application to automate all the processes in manufacturing. Imagine if a developer needed to thoroughly study the subject area before writing code. How long would it take him to implement the project? An SRS is designed to simplify the developer's life and satisfy all the customer's needs in the shortest possible time frames.
Well-written Software Requirements Specifications provide customers with feedback, deconstructs the problem, aids in generating subsequent documents, and serves as a template for testing and validation strategies.
Software Requirements Specification Template
To begin with, you should find a ready-made template and remake it depending on your needs. It is quite important to focus on this stage. There are enough effective examples out there that can be used to get started. The above template is suitable for many projects. It consists of the following sections:
Index
- 1.1. Purpose
- 1.2. Document conventions
- 1.3. Intended audience
- 1.4. Additional Information
- 1.5. References
- Overall description
- 2.1. Product perspectives
- 2.2. User classes and characteristics
- 2.3. Operating environment
- 2.4. User environment
- 2.5. Design and implementation constraints
- 2.6. Assumptions and dependencies
- Functional Requirements
- 3.1. System feature X (there may be several features)
- 3.2. Description and priority
- 3.3. Action/Result
- 3.4. Functional Requirements
- Requirements for external interfaces
- 4.1. User Interfaces
- 4.2. Hardware Interfaces
- 4.3. Software Interfaces
- 4.4. Communication protocols and interfaces
- Nonfunctional Requirements
- 5.1. Performance Requirements
- 5.2. Safety Requirements
- 5.3. Security Requirements
- 5.4. Software quality attributes
- 5.5. Project Documentation
- 5.6. User Documentation
Other Requirements
It is important to note that this template should be thoroughly restructured and all the necessary elements must be adjusted in it instead of just downloading a template for a project similar to yours and use it as your own.
Despite such a large number of points that are included in this specification, the "core" of the application requirements is still in the functional requirements. Often, they are presented in the form of user scenarios (Use cases).
Description of Software Requirements Specification Template Sections
Introduction
The introduction is an overview that allows people to understand the structure and usage principles of the software requirements specification.
1.1. Purpose
This section contains the definition of the product or application discussed in this document. If this software requirements specification applies only to a part of the system, that part or subsystem should be identified. In other words, here we must define the problem that this project is intended to solve.
1.2. Document conventions
Not the most important section, but it helps to save some time during the document learning. Here are described all text formats that are used in this document. For instance, if you are using color-coding, bold text, etc., you should describe the definition of these formats in this section.
1.3. Intended audience
The intended audience includes the description of readers for whom this document is intended. For example, it could be developers, project managers, users, testers, etc. The main goal of this section is to convey to the readers the information they need to know before reading this document.
1.4. Additional Information
Any additional information about the product or application described should be included in this section. For instance, here we can describe the scope of the project. This section provides information about how, where, and for what the product or application will be used. The product relative to users or corporate goals, as well as to business goals and strategies should be shown.
1.5. References
Here should be mentioned all resources which this document refers to. The users should have the possibility to access every single specified material.
Overall description
The overall description section should be described as the overall review of the product and the environment where it will be applied. Also, it would not be superfluous to mention the description of the custom audience, as well as the known limitations, assumptions, and dependencies.
2.1. Product perspectives
Product perspectives give an understanding of the origin of the product, whether it is a new product or is a component of large-scale production. In the second case, the connection and interaction between the products should be considered.
2.2. User classes and characteristics
This section contains a list of all user classes that will work with the product. Different users often have different capabilities and permissions. It should be taken into account during describing the characteristics of each class.
2.3. Operating Environment
The next section provides information about hardware and software (operating system) characteristics that should be able to run the application. Also, the operating environment includes data about the location of users, servers, databases.
2.4. User Environment
Describe all user environments that will work with the application. Also add additional information about the users, their permissions, and how they should interact with the system.
2.5. Design and implementation constraints
If there are any preferences or needs in using certain hardware, programming languages, design components, these requirements must be listed here. It is important to competently argue for the presence of certain restrictions as they complicate the work of developers.
2.6. Assumptions and dependencies
Here should be listed all assumptions which could cause problems with application health problems. Also here should be added all dependencies, for instance, if we need to pre-install any software or hardware to use the application, we need to mention it here.
Functional Requirements
Thus, we come to the most important and interesting component of this template - Functional Requirements. There should be a list of functional capabilities that the product should have. These requirements identify tasks or activities that have to be performed.
3.1. System feature X
Contains the name of the feature. There can be a large number of features, so X here is a feature number from the set.
3.2 Description and priority
In the previous section, the feature was specified. Here we need to give the description of it and set a priority, in other words, the importance and necessity of this requirement.
3.3. Action/Result
The next is the result expected from the function X execution.
3.4 Functional Requirement
The last step here - formulating the list of requirements related to function X. These functions must be implemented by the programmer in order to execute the function and get the expected result. In this section, everything should be indicated to the smallest detail. Product response to incorrect data entry, errors, hints, and much more.
Requirements for external interfaces
The interaction between the user and the application is quite an important aspect and it needs to be paid enough attention at the design stage. The system should work correctly and quickly. The number of bugs should be minimized, and the user should enjoy interacting with the application, but not get nervous and freak out about the fact that the program does not work as he wants. This section is dedicated to exactly this.
4.1. User Interfaces
It contains the characteristics of all user interfaces that require the system. To form a set of such interfaces, you can refer to international software quality standards. In this case, it could be GUI standards, standards for fonts, icons, button names, images, color schemes, tab sequences, commonly used controls, branding graphics, and more.
4.2. Hardware Interfaces
These interface characteristics describe the connection between the application and the hardware resources. For example the availability to connect additional devices, application control using this device, and communication protocols that must be used.
4.3. Software Interfaces
The connection of the current application with other software products or components should be described here. For example, if the application will be connected with a database to store the data there, it should be mentioned in the Software Interfaces section with the description and purpose of the connection.
4.4. Communication protocols and interfaces
Here contains the list of communication functions that will be used by applications such as E-mail, browser, network protocols, and electronic forms. Also, it is worth mentioning the security of interaction or encryption, the speed of data transfer, and the mechanisms of coordination and synchronization here.
Nonfunctional Requirements
5.1. Performance Requirements
Performance Requirements include the limitations regarding, for example, interface response time, time is taken to perform a specific action in a system, or other time limitations that should be taken into account by developers in the development process.
5.2. Safety Requirements
These requirements stand for protecting the user from damage or loss of data with which he operates while working with the application.
5.3. Security Requirements
These requirements are extremely crucial because all user data must be protected. Here should be defined all requirements which will allow secure all data as reliable as it only could be.
5.4. Software quality attributes
Here must be included the listing of all requirements regarding software quality, such as adaptability, availability, correctness, flexibility, maintainability, portability, reliability, testability, and usability, and others. All software quality criteria are available in standard ISO/IEC 25010.
5.5. Project Documentation
Project Documentation must lay the foundation for quality, traceability, and history for both the individual document and for the complete project documentation. It is also essential that the documentation is well arranged, easy to read, and adequate.
5.6. User Documentation
As the name suggests, user documentation is created for product users. However, their categories may also differ. So, here should be listed the requirements which will help to structure user documentation according to the different user tasks and different levels of their experience.
Other Requirements
Finally, in the last section may be all requirements that were not included in the above sections. It could be legal or financial requirements and standards requirements, requirements for installing, configuring, starting, and stopping a product, and other requirements.
Conclusion
This article provides a detailed structure of the SRS template. The well-written SRS template can significantly speed up the development process and save the company from unnecessary spending. We examined all the components of this document in order to fully explain the meaning of the SRS template.
I hope this article will help you simplify your development process and get the results you want.
Previously published at https://kitrum.com/blog/how-to-write-software-requirements-specifications/