CP317B Software Engineering High-Level Design PDF

CP317B Software Engineering Architecture design, part-1 – week 3-1 Shaun Gao, Ph.D., P.Eng. Agenda Review week 2 Introduction to high-level design Software Security User interface Architecture design Monolithic Client/server Component...

CP317B Software Engineering Architecture design, part-1 – week 3-1 Shaun Gao, Ph.D., P.Eng. Agenda Review week 2 Introduction to high-level design Software Security User interface Architecture design Monolithic Client/server Component-based Service-oriented Event-driven Data-centric Distributed Summary Review week 2 MOSCOW method FURPS and FURPS+ methods Functional requirements, Non-functional requirements Requirement elicitation Six techniques: communication, task analysis, domain analysis, brainstorm, prototype, observation Alex F. Osborn four rules about brainstorm Requirements documentation Requirements validation and verification Verification vs. validation Introduction Design Design is a problem-solving process whose objective is to find and describe a way to implement the system’s functional requirements while respecting the constraints imposed by non-functional requirements (for example, performance, security, and etc.) and while adhering to general principles of good quality. High-level design(HLD) – architecture design HLD provides a view of the system at an abstract level. It shows how the major pieces of the software product will fit together and interact with each other. HLD describes an architecture that would be used for developing a software product. Architecture design - project Think-Pair-Share Question: what is architecture design from SE perspective? High-level design considerations Reliability, software product continue working when receiving any inputs. Quality, Software Security Software security is an implemented idea/technique that protects a software system against malicious attack and other hacker risks so that the software system continues to function correctly under such potential risks. Software security should be considered at system design level Software vulnerability is the main cause of cyber security. Buffer overflow attacks SQL injection Cross-site Scripting … High-level design considerations – cont. User interface User interface is a (visual) part of a computer application or operating system through which a user interacts with a computer or a software system. Examples of user interfaces Keyboard, mouse Touch screen, voice recognition, Windows login screen Architectural design What is Architecture? Architecture is a high-level model of a thing Architectural design of software engineering Architectural design is the process of defining a collection of hardware and software components and their interfaces to establish the framework for the development of a software system. Models of architecture design Monolithic Client/server Component-based Service-oriented Data-centric Event-driven Distributed Architecture design Monolithic architecture (MA) MA is to put all functions into a single program that does everything. Advantage: No need for communication across networks Disadvantage: Lack flexibility and scalability Examples: Software used in current washing machine JPA: Java Persistence API Software used in current home appliances CDI: Contexts and Dependency Injection REST: Representational State Transfer JSF: JavaServer Faces CSS: Cascading Style Sheets Architecture design – cont. Client/server architecture Client/server architecture is a computing model in which the server hosts, delivers and manages most of the resources and services to be consumed by the client. Advantage: Scalability and flexibility Disadvantage: Security Architecture design – cont. Client/server architecture-cont. Client/server architectures have multiple tiers. For example: web app, DNS, …  Architecture design – cont. Component-based architecture A component is a software object, intended to interact with other components, encapsulating certain functionality or a set of functionalities. Component-based architecture focuses on the decomposition of the design into individual functional or logical components that represent well-defined communication interfaces containing methods, events, and properties. It provides a higher level of abstraction and divides the problem into sub-problems, each associated with component partitions. Decomposition  Architecture design – cont. Component-based architecture –cont. A component is viewed as a functional element or a module of a software product. Example: ATM: Advantage: Easier for understanding, shorten production time Disadvantage: Lack flexibility and scalability Architecture design – cont. Service-oriented architecture Service-oriented architecture is a style of software design where services are provided to the other components by application components, through a communication protocol over a network. Advantage: Services are easily maintained; reliability; availability; scalability Disadvantage: Increased overhead. E.g. customer needs Examples: Cloud computing: Software as a service; platform as a service Symmetric key management systems Architecture design – cont. Data-centric architecture Data centric architecture is a software design model where data is the primary and permanent asset, and applications come and go. Database plays an important role Advantage: Simplicity; security; integrity management Disadvantage: performance Example: Data Warehouse Question? Data-centric architecture vs. client/server Architecture design – cont. Data-centric architecture vs. Client/server architecture Architecture design – cont. Event-driven architecture (EDA) Event: an occurrence that may trigger a state transition. EDA is a software architecture pattern that the behavior of the software system based on events. Two types of events Hardware vs. software Advantage: Good performance Disadvantage: Complexity (cause race condition) Architecture design – cont. Event-driven architecture (EDA) example – State transition diagram Architecture design – cont. Distributed architecture In distributed architecture, components are presented on different platforms and several components can cooperate with one another over a communication network in order to achieve a specific objective or goal. Advantage: Resource sharing; scalability Disadvantage: Complexity; security Examples: MongoDB – non-SQL DB Block Chain Think – Pair – Share Question 2: Architecture design of group project Design and develop a software application to read two text files Architecture design and format the data output to a new file (Note: the format of input file and output file is described in Appendix A). Monolithic The design should contain both architecture design and detailed Client/server design. Component-based Service-oriented Data-centric Event-driven Distributed For the group project, which architecture design is more suitable? Summary Software Security Security should be considered at system design phase User interface Concept Architecture design Monolithic Client/server Component-based Service-oriented Data-centric Event-driven Distributed Announcement 25% of you have found a group for the group project Please let me know if you need help.