Gathering needs and expectations from stakeholders to meet

organizational goals.

(a)  

Requirements Elicitation Techniques include:

(a)  

Direct discussions with stakeholders.

(a)  

Questionnaires to collect data on requirements.

(a)  

Group discussions for feedback.

(a)  

Clear, detailed documentation of requirements for developers

and designers.

(a)  

Ensures requirements are correct, feasible, and meet stakeholders' needs.

(a)  

Requirements Verification and Validation Activities include:

(a)  

Formal review of requirements documents.

(a)  

Creating a prototype to verify requirements visually.

(a)  

Tracks and maintains requirements throughout the project, handling changes and ensuring proper implementation.

(a)  

Creation of abstract representations of a system’s structure, behavior, and interactions to simplify complex systems and aid communication.

(a)  

System Modeling Types:

(a)  

Different Perspective of Models:

(a)  

Focuses on system interaction with external entities.

(a)  

Shows communication and collaboration over time.

(a)  

Describes system components and relationships.

(a)  

Details system reactions to events or inputs.

(a)  

Example: Model of a weather app showing interactions with satellites and weather stations.

(a)  

Example: Model showing data flow in a weather app from user input to data display.

(a)  

Example: Hospital system model showing relationships between patient registration,

billing, and scheduling.

(a)  

Example: Model of the login process in an online banking system, showing responses based on user actions.

(a)  

Standardized visual language for creating system models.

(a)  

Define system boundaries and interactions with external elements.

(a)  

Describe workflows and business processes within the system.

(a)  

Interaction Models:

(a)  

Shows user interface and actions.

(a)  

Communication between systems.

(a)  

Communication between software modules.

(a)  

Interaction Models

(a)  

Example: Mobile banking app model showing flow from login to funds transfer.

(a)  

Example: Inventory system communicating with a shipping system to schedule

deliveries.

(a)  

Example: Payment processing module in an e-commerce platform interacting with the UI

and database.

(a)  

A standardized visual language for creating system models, aiding in documenting, visualizing, and designing complex systems.

(a)  

Unified Modeling Language (UML):

(a)  

Represent workflows, highlighting actions and decisions.

(a)  

Show interactions between the system and users, outlining system functionality from a user perspective.

(a)  

Detail the sequence of interactions between components or objects.

(a)  

Represent the static structure of a system, showing classes and their relationships.

(a)  

Depict object states and transitions between them based on events.

(a)  

Use of mathematical models to precisely define software behavior, constraints, and operations.

(a)  

Ensure correctness, consistency, and clarity in software development.

(a)  

System Prototypes:

(a)  

Serve as a practical implementation of formal specifications, helping validate their accuracy and usability.

(a)  

Prototypes help confirm that formal specifications align with user needs.

(a)  

Allows stakeholders to provide input for refining specifications.

(a)  

Specification sets goals, and design creates solutions.

(a)  

Specification and design influence each other throughout development.

(a)  

Different Stages of the Development Life Cycle:

(a)  

Formal specification ensures precise documentation and validation of user and system requirements.

(a)  

Formal specification guides system design by defining structure and behavior clearly.

(a)  

An implementation directly follows the behavior and constraints defined in the

formal specification.

(a)  

Formal specifications provide test cases and expected outcomes for validation.

(a)  

Formal specifications help certify systems for safety and compliance with industry standards.

(a)  

Formal specifications provide a clear and consistent foundation for user manuals and documentation.

(a)  

A collection of independent computers that appears to its users as a single

coherent system.

(a)  

Goals of Distributed Systems:

(a)  

Hides complexity from users (e.g., access, location, replication).

(a)  

Ensures systems can handle increased load.

(a)  

Continues functioning despite failures.

(a)  

Two Essential Concepts of Distributed System:

(a)  

Logical organization of software components and their interaction with other structures.

(a)  

Focuses on the entire system and the placement of components across multiple machines.

(a)  

A system where clients request services from centralized servers.

(a)  

Decentralized architecture where peers act as both clients and servers.

(a)  

Architectural Models of Distributed Systems:

(a)  

Individual devices in the system (e.g., servers, workstations).

(a)  

Communication backbone (e.g., LAN, WAN).

(a)  

Rules governing data exchange (e.g., HTTP, TCP/IP).

(a)  

Software providing abstraction and coordination among components.

(a)  

Examples include messaging and transaction processing.

(a)  

Perform computations across multiple nodes.

(a)  

Manage and share information among multiple nodes.

(a)  

Coordinate sensors and actuators over a network.

(a)  

Components of Distributed Systems:

(a)  

Types of Distributed Systems:

(a)