How to analyze software requirements (Summary of personal work experience)

Directory:

Preface:

1What is demand and the role of demand analysis throughout the development cycle.

2Three Milestones in the demand process

2.1Stage 1Determine the project background

2.2Stage 2Definition and Determination of core requirements in this phase of the project

2.3Stage 3Detailed project Requirement Analysis

 

Preface:

Demand is a familiar term for our IT people. How to make demands in the project development cycle is different, the following is my understanding and summary of the requirements in the software development process. I hope it will bring you a little different senses.

 

1What is demand and the role of demand analysis throughout the development cycle.

The requirement concept is Function + quality + constraint. Throughout the development cycle, requirements are the basis of the entire development. If the requirement analysis is successful, the software risk is halved.

In this case, it is quite empty. For us, how should we analyze the needs? What is the process and the standard of each process?

In the demand operation, I mainly divided into three stages.

The first stage determines the background of the project. Define and determine the core requirements of the Phase-2 project, and analyze the detailed requirements of the Phase-3 project.

 

2Three Milestones in the demand process

2.1Stage 1Determine the project background

Determining the project background is to fully understand the project field and the customer's expectations for the project. Secondly, for enterprise projects, after determining the project objectives, we need to further understand the customer's enterprise framework. The position of the current project in the enterprise framework, the definition of third-party interfaces, and so on.

After taking into account the business preview, the next step is to implement the technical implementation scheme of the project, and select the technical framework (usually including the development platform, third-party components, hardware environment, and test environment) to implement the project, deployment environment)

 

Configuration items in the first phaseIs

Enterprise Construction Plan

 

2.2Stage 2Definition and Determination of core requirements in this phase of the project

In the context of determining the requirements, what we need to do next is to determine the core functions, key quality, and related constraints of the project. Here, I would like to explain to you the two-dimensional requirement table of instructor Wen Yi.

 

The table format is

	Function	Quality	Constraints
Business and needs
User-level requirements
Development-level requirements

 

Function:

Software functions are classified into key functions and secondary functions. In the second stage, what we need to do is to distinguish and sort out key and secondary functions. Find out the key functions to be implemented based on the project plan. At the same time, make a preliminary trade-off between functions with high risks, high technical risks, or conflicting key functions. (Of course, we need to communicate with customers when selecting and determining specific functional scopes)

The last thing to add is that the process of determining key functions is a process of continuous recursion.

 

 

Quality:

General Quality classification includes performance, security, reliability, ease of use, scalability, maintenance, and portability.

In requirement analysis, like key functions, key quality needs to be screened based on the project's vision.

In some cases, there is still a conflict between the quality of the software, and the fish and the bear's paw cannot have both sides. For example, maintainability and performance are two opposite brothers. We also need to make necessary trade-offs on such key quality. When making such a trade-off, the standards are derived from the first stage of our needs.

 

Constraints:

Software constraints are divided into many aspects,

Business-level constraints: for example, the project's organizational structure and personnel information are from the enterprise's Personnel System

User-level constraints: for example, users who are using a part of the customer are persons with disabilities, including Tibetan users.

Development-level constraints: for example, the technical level of developers.

 

After investigating and completing such a two-dimensional requirement table, you can communicate with the customer in a timely manner to determine key functions, key quality, and constraints. Select and determine the content in the two-dimensional requirement table.

 

Configuration items in the second stage

 Two-dimensional demand table

 

2.3Stage 3Detailed project Requirement Analysis

On the basis of the second stage, we can conduct data flow requirement investigation and analysis and business logic analysis on the core functions of the project. And writeUser Cases , Data flow chart,Business Logic DiagramAnd so on

After completing the detailed investigation and analysis of the above core business functions, combine all the use cases and other content to develop the project requirement specification.

 

Configuration items in stage 3

Project requirement specification.