Gather information
Obtain information from the user/s who will be using the system,
Define System Requirements
Creates models based on the information gathered
Logical model
shows what the system is required to do in detail, without committing to any technology.
Physical model
shows how the system will be implemented.
Prioritize Requirements
Determine and verify which functional and technical requirements are most crucial for the system.
Prototype for Feasibility and Discovery
Create prototype (often called discovery prototype) to better understand user’s needs and check the feasibility of certain approaches to the business need.
Generate and evaluate alternatives
Define and evaluate all possibilities in designing developing the system.
Review recommendations with management
Recommend a solution and obtain a decision from the management
System Requirements
detailed statements of what the system must do in order to satisfy the needs and requirements.
Functional Requirements
functions that the system is expected to perform.
Non-functional Requirements
focus on user expectations, defines how the system should do it.
Stakeholders
refer to everyone that is involved in the system.
Users
who actually use the system on a daily basis
Clients
who pay for and own the system
Technical Staff
who must ensure that the system operates in the computing environment of the organization.
Business Users
Who use the system to perform day-to-day operations of an organization.
Information Users
Who needs current information from the system.
Management Users
Who needs statistics and summary from the system. Responsible for seeing that the company is performing its daily procedures efficiently and effectively
Executive Users
Typically want information from a system so that they can compare overall improvements in resource utilization
External Users
Customers may access the system directly through the Internet. Suppliers may have access to a system to check inventory levels and to initiate billing transactions.
Use Case
An Activity that the system performs in response to user’s request.
User Goal Technique
Use case identifying trehnique where the system analyst talks to the users to describe what the users goals are in using the system.
CRUD technique
Use case identifying technique where system analyst look each type of data and includes use cases that Create, Read, Update, Delete data
Event Decomposition Technique
Use case identifying technique whch focused on idetifying events that the system must respond and determine how the system should respond.
External Events
Event Decomposition Technique type of event that occurs outside the system, initiated by external agent.
Temporal Events
Event Decomposition Technique type of event that occurs after reaching a specific point in time. Occurs after a defined period of time has elapsed.
State Events
Event Decomposition Technique type of event which occurs when something happens inside the system that triggers the need for processing.
Perfect Technology Assumption
Assumes that the system runs under a perfect techological condition.
Trigger
Part of Event Table which is a signal that informs the system that an evwent has occured.
Source
Part of Event Table which knowing where the data came from.
Response
Part of Event Table which is the output produced by the system.
Destination
Part of Event Table where the response(output) is sent.
use case diagram
a graphical model that summarizes the details of users known as actors and their interactions with the system.