Chapter 2 requirement analysis and Requirement documents

Chapter 2 requirement analysis and Requirement documents

What is demand analysis? Requirement analysis refers to a detailed analysis of the problem to be solved to clarify the requirements of the problem. In web development, "requirement analysis" is to determine what computers are required to do. Therefore, it is necessary to clarify what data is needed, what results are obtained, and finally what to output.

Software requirements include three different layers: business requirements, user requirements, and functional requirements.

Business Requirements(Business Requirement)A high-level goal of an enterprise or a customer. Business Requirements describe why an enterprise wants to develop a website, that is, what it wants to achieve, they generally come from project investors, customers who purchase products, managers of actual users, marketing departments, or product planning departments. Use vision and scope documents to record business requirements. This document is also called a project profile or market requirement document.

User Requirements(User requirement)Indicates the user's target or the task that the user requires the system to complete.. User requirements are collected, sorted, and written into a document from different perspectives. That is to say, the user requirement describes what the user can do with the system.

Functional requirements(Functional requirement)Specifies the software functions that developers must implement in the product. Users can use these functions to complete tasks and meet business needs.. Functional requirements are sometimes referred to as behavior requirements (behav response oral requirement), because they are often described as "should: "The system should send an email to notify users that they have accepted their reservation ". Description of functional requirements is what developers need to implement.

What is the process of requirement analysis? After years of working experience, we recommend that you use the following steps to develop your website:

Obtain user requirements → user requirement analysis → write Requirement documents → review requirement documents → manage requirements.

Next we will gradually discuss the above practices.

It was a simple process to obtain the user's needs, as long as the customer provided a complete description of the requirements, but this is not the case, many customers are not very clear about their needs, you need continuous guidance and help analysis. Once upon a time, I asked the customer, "What is your website's purpose ?" He replied, "there is no purpose, just because everyone else has it. I don't have it !". This type of customer needs to be patiently explained, analyzed carefully, and found out his potential and real needs. It will take a lot of time for the customer to write a detailed and complete Requirement Description, however, this is worthwhile and must satisfy the customer and sign for approval. By setting this level, you can avoid many mistakes and project failures caused by unclear requirements or misunderstanding.

Further analysis and organization are required to obtain user requirements. To analyze user requirements, follow the following common guidelines:

(1) You must know the "why" for each requirement raised by the user and determine whether there are sufficient reasons for the requirement;

(2) convert the expression "How to Achieve" to "what to achieve", because the goal of the demand analysis stage is "what to do", rather than "how to do ";

(3) analyze the implicit requirements derived from user requirements and identify the hidden requirements that are not explicitly proposed by the user (which may be a prerequisite for implementing user requirements). This is often overlooked, demand changes are often caused by insufficient considerations for implicit requirements.

By analyzing the customer's needs, we need to make the requirement statement meet the following standards:

1. correctness: each function must clearly describe the delivery function;

2. Feasibility: ensure that each requirement can be met in the current development capability and system environment;

3. Necessity: whether the function must be delivered, whether the implementation can be postponed, and whether the function can be "chopped" when the expenditure reduction occurs;

4. Concise: Do not use professional network terms;

5. Detection: If the development is complete, the customer can detect the problem as needed.