Fundamentals of Software Architecture |《软件架构基础》

Fundamentals of Software Architecture
02 Dec, 2022
In the world of technology, starting from small children to young people and starting from young to old people everyone using their Smartphones, Laptops, Computers, PDAs etc to solve any simpler or complex task online by using some software programs, there everything looks very simple to user. Also that’s the purpose of a good software to provide good quality of services in a user-friendly environment. There the overall abstraction of any software product makes it looks like simple and very easier for user to use. But in back if we will see building a complex software application includes complex processes which comprises of a number of elements of which coding is a small part.
After gathering of business requirement by a business analyst then developer team starts working on the Software Requirement Specification (SRS), sequentially it undergoes various steps like testing, acceptance, deployment, maintenance etc. Every software development process is carried out by following some sequential steps which comes under this Software Development Life Cycle (SDLC).
In the design phase of Software Development Life Cycle the software architecture is defined and documented. So in this article we will clearly discuss about one of significant element of Software Development Life Cycle (SDLC) i.e the Software Architecture.
Software Architecture :
Software Architecture defines fundamental organization of a system and more simply defines a structured solution. It defines how components of a software system are assembled, their relationship and communication between them. It serves as a blueprint for software application and development basis for developer team.
Software architecture defines a list of things which results in making many things easier in the software development process.
• A software architecture defines structure of a system.
• A software architecture defines behavior of a system.
• A software architecture defines component relationship.
• A software architecture defines communication structure.
• A software architecture balances stakeholder’s needs.
• A software architecture influences team structure.
• A software architecture focuses on significant elements.
• A software architecture captures early design decisions.
Characteristics of Software Architecture :
Architects separate architecture characteristics into broad categories depending upon operation, rarely appearing requirements, structure etc. Below some important characteristics which are commonly considered are explained.
• Operational Architecture Characteristics :

1. Availability
2. Performance
3. Reliability
4. Low fault tolerance
5. Scalability
   • Structural Architecture Characteristics :
6. Configurability
7. Extensibility
8. Supportability
9. Portability
10. Maintainability
    • Cross-Cutting Architecture Characteristics :
11. Accessibility
12. Security
13. Usability
14. Privacy
15. Feasibility
    SOLID principles of Software architecture :
    Each character of the word SOLID defines one principle of software architecture. This SOLID principle is followed to avoid product strategy mistakes. A software architecture must adhere to SOLID principle to avoid any architectural or developmental failure.

S.O.L.I.D PRINCIPLE

1. Single Responsibility –
   Each services should have a single objective.
2. Open-Closed Principle –
   Software modules should be independent and expandable.
3. Liskov Substitution Principle –
   Independent services should be able to communicate and substitute each other.
4. Interface Segregation Principle –
   Software should be divided into such microservices there should not be any redundancies.
5. Dependency Inversion Principle –
   Higher-levels modules should not be depending on low-lower-level modules and changes in higher level will not affect to lower level.
   Importance of Software Architecture :
   Software architecture comes under design phase of software development life cycle. It is one of initial step of whole software development process. Without software architecture proceeding to software development is like building a house without designing architecture of house.
   So software architecture is one of important part of software application development. In technical and developmental aspects point of view below are reasons software architecture are important.
   • Selects quality attributes to be optimized for a system.
   • Facilitates early prototyping.
   • Allows to be built a system in component wise.
   • Helps in managing the changes in System.
   Besides all these software architecture is also important for many other factors like quality of software, reliability of software, maintainability of software, Supportability of software and performance of software and so on.
   Advantages of Software Architecture :
   • Provides a solid foundation for software project.
   • Helps in providing increased performance.
   • Reduces development cost.
   Disadvantages of Software Architecture :
   • Sometimes getting good tools and standardization becomes a problem for software architecture.
   • Initial prediction of success of project based on architecture is not always possible.
   From above it’s clear how much important a software architecture for the development of a software application. So a good software architecture is also responsible for delivering a good quality software product.

《软件架构基础》
2022年12月2日
在当今科技世界中，从儿童到年轻人，再到老年人，每个人都使用智能手机、笔记本电脑、计算机、个人数字助理（PDA）等设备，通过各种软件程序在线解决简单或复杂的任务。对于用户来说，这一切看起来都非常简单。这正是优秀软件的初衷——在用户友好的环境中提供优质服务。软件产品的整体抽象化使其看起来简单易用。然而，如果我们深入幕后，会发现构建复杂的软件应用程序涉及复杂的过程，其中编码只是很小的一部分。
在业务分析师收集业务需求后，开发团队开始着手软件需求规格说明书（SRS），随后依次经历测试、验收、部署、维护等步骤。每一种软件开发过程都遵循一些顺序步骤，这些步骤属于软件开发生命周期（SDLC）。在软件开发生命周期的设计阶段，定义并记录了软件架构。因此，本文将深入探讨软件开发生命周期（SDLC）的一个重要元素，即软件架构。
软件架构：
软件架构定义了系统的根本组织结构，更简单地说，它定义了一个结构化的解决方案。它定义了软件系统的组件如何组装、它们之间的关系以及它们之间的通信方式。它为软件应用程序和开发团队提供了蓝图。
软件架构定义了一系列内容，从而使软件开发过程中的许多事情变得更加容易：
软件架构定义了系统的结构。
软件架构定义了系统的行为。
软件架构定义了组件之间的关系。
软件架构定义了通信结构。
软件架构平衡了利益相关者的需求。
软件架构影响团队结构。
软件架构专注于重要元素。
软件架构捕捉早期设计决策。
软件架构的特征：
架构师根据操作、罕见需求、结构等因素将架构特征分为广泛的类别。以下是一些通常被认为重要的特征的解释：
操作架构特征：
可用性
性能
可靠性
容错性低
可扩展性
结构架构特征：
可配置性
可扩展性
可支持性
可移植性
可维护性
跨领域架构特征：
可访问性
安全性
易用性
隐私性
可行性
SOLID原则：
SOLID原则中的每个字母代表一个软件架构的原则。遵循SOLID原则是为了避免产品策略错误。软件架构必须遵循SOLID原则，以避免任何架构或开发失败。
S.O.L.I.D 原则：
单一职责原则（Single Responsibility）：
每个服务应有一个单一目标。
开闭原则（Open-Closed Principle）：
软件模块应独立且可扩展。
里氏替换原则（Liskov Substitution Principle）：
独立服务应能够相互通信并相互替换。
接口分离原则（Interface Segregation Principle）：
软件应被划分为微服务，避免任何冗余。
依赖倒置原则（Dependency Inversion Principle）：
高层模块不应依赖低层模块，高层的变化不应影响低层。
软件架构的重要性：
软件架构属于软件开发生命周期的设计阶段，是整个软件开发过程的初始步骤之一。没有软件架构就进行软件开发，就像在没有设计房屋架构的情况下建造房屋一样。因此，软件架构是软件应用开发的重要组成部分。从技术和开发的角度来看，以下是软件架构重要的原因：
选择要优化的系统质量属性。
便于早期原型设计。
允许以组件化方式构建系统。
有助于管理系统的变更。
除了这些，软件架构对于软件的其他因素也很重要，例如软件的质量、可靠性、可维护性、可支持性和性能等。
软件架构的优势：
为软件项目提供坚实的基础。
提高性能。
降低开发成本。
软件架构的劣势：
有时获取良好的工具和标准化对软件架构来说是一个问题。
基于架构的项目成功预测并不总是可能的。
从上述内容可以看出，软件架构对于软件应用的开发是多么重要。因此，良好的软件架构也是交付高质量软件产品的关键。