Software Requirement Specification: a Foundation for Building a Successful Application

What is the Software Requirement Specification (SRS)?

A Software Requirement Specification (SRS) is a document fully describing a product such as what the software will do and how it performs. Also, this document includes the project’s goals, technical and non-technical requirements as well as the tasks for software accomplishment.

You need to distinguish Software Requirement Specification and System Requirement Specification which also stands for SRS. A System Requirement Specification collects information for a system’s requirements. Meanwhile, a Software Requirement Specification contains not only requirements but also the process of development. In terms of information, a Software Requirement Specification provides intensive details.

The Advantages of SRS

Although SRS is not the main part of the development life cycle, it is incredibly important because:

• SRS contains the framework that the development team will follow.
• It ensures that project members are on the same page: providing critical information about development, quality testing, operations and maintenance to multiple teams.
• It helps to make decisions regarding the product’s life cycle, based on the fulfilled requirements on SRS
• SRS might involve reducing development time and budget.
• SRS provides an accurate estimation of budget, risks, and schedules.
• SRS clarifies the client’s vision.
• SRS contains the most important features, eliminates the unnecessary ones, and avoids task duplication.
• SRS provides the way to structure, address and solve problems easily.

Writing an SRS Document

Microsoft Word: This is the easiest way to create an SRS. You can even make a template to use in any project. However, for a more complicated SRS, this SRS can be out of date if a requirement changes. The Microsoft Word version not only wastes your time but also can’t guarantee accuracy.

Helix ALM: has a dedication requirements management tool that improves the requirements control process. When creating an SRS in Helix ALM, you control all sources of truth and review requirements. An SRS (Helix ALM version) get faster approvals and starts your project quickly.

PRD: links the requirements in SRS to tests. It helps to check if the finished product fulfills the goal and requirements of your SRS.

How to Write an SRS: A Software Specification Template

Create an Outline

You can do this first step by yourself. A typical outline includes:

Part 1 – Introduction:

You should define the purpose of your app, your target audience, and your app’s benefits. Also, you can write a scope of work about what should and shouldn’t do. It’s better if you can provide a chapter with definitions, acronyms, and abbreviations to explain all the referred specific terms. This will make your SRS more understandable.

Part 2 – Overall description:

The main part of SRS covers the major actors of the product such as user needs, assumptions, and dependencies.

• Product perspective: decides the dependence or independence of the product. This chapter states whether the product will be an app or just be a part of the bigger system. if it’s a part, you must describe the products’ relevance to others.
• Product features: lists the functions of the software. People can see this part to understand the product.
• Target audience annalistic: describes users, their behaviors, their interaction and their influences on the product.
• General constraints: points out existing limitations for developers concerning system design.

Part 3 – functional requirements in SRS:

The core part of SRS helps developers find all necessary information to build the software correctly. You should represent this chapter logically. Typically, this part includes functional and non-functional requirements.

• Functional requirements: things an app does. This part declares how input will be transformed into output and lists the required operations.
• Non-functional requirements: give the criteria of the software functioning evaluation such as productivity, data safety, performance, quality, and system security.
• External interface requirements are types of functional requirements. They describe how your product interfaces with other elements. There are four types of interfaces having requirements: user, hardware, software, and communication.
• System features: types of functional requirements. A system needs these functions to run.
• Special requirements: includes the Data flow diagram (cover the input/output data and their sources, destinations, places of storage) and Use case diagram (describes how objects interact with the software, map out the basic functions).

Mockups

To make SRS understandable for your client, you can build mock-ups based on SRS. Your client can see the basic structure and usability of the app.

Get your SRS approved

When your SRS is done, you need to get it approved by key stakeholders. In this stage, your team members can review the latest version of SRS.

Refinement

The SRS is modified until it meets your team members’ and client’s expectations.

Proposal and Milestones

The project is broken down into milestones before going through the development process.

This article provides you the most important elements of Software Requirement Specification. Go for it!