Bide A-While Context and Data Flow Diagram
Context DiagramContext diagram is a high level representation of the business processes. It defines the entities and their interaction in the system. This is one of the important tools for stakeholders to understand the required process. The objective of the system context diagram is to focus attention on external factors and events that should be considered in developing a complete set of systems requirements and constraints.Building BlocksContext diagrams can be developed with the use of two types of building blocks:Entities (Actors): labeled boxes; one in the center representing the system, and around it multiple boxes for each external actor.
Represented as Name
Relationships: labeled lines between the entities and systemRepresented as NameProcess: Achieve desired functionality for some specific business reason.Represented as Number Name
nn
Name
p
rR
Data store: Collection of data which form starting point of a data model and principal link between data model and process model
Represented as D1 Name
Types of External Entities in Bide-A-While case1) Active: Entities which are dynamic to achieve purpose Example: Customer, Receptionist and Manager2) Passive: Static External entities that interact infrequently with the system.
Example: Quality assurance team, Audit manager etc.3) Cooperative: Entities that are used by system for desired outcome. Example: Internet Service Provider, Net Banking services4) Autonomous: Entities that are separated from the system affecting indirectly. Example: Media partners, advertising agencies etc. Context Diagram of Bide-A-While
Fig 1: Bide-A-While Electronic Reservation System Context Diagram
Data Flow Diagram
Data Flow Diagram a graphical representation of the flow of data through the system. This is an intuitive way to analyze data processed in the systemIn this system there are three major processes. Below are the fragmented processes (Fig: 2 to Fig: 4) and Fig 5 is the Level 0 Data Flow Diagram for Bide-A-While Electronic Reservation System Project.
1] Process 1: Book A ReservationUse Case Name: Booking a ReservationID: UC-1Priority: High
Actor: Receptionist/Manager
Description: Customer requests for reservation, receptionist, manager checks rooms availabity and books the room.
Trigger: Customer enquires about room Type: ExternalNormal course: Refer to fig 2, Book A Reservation.
InputsSource OutputsDestination
1.Customer name2.Address3.Credit card details4. Occupancy
Electronic reservation of Bide-A-WhileReservation confirmation details such as reservation code, room no etc.Customer
1.Book A Reservation
Fig 2: Bide-A-While Electronic Reservation System Fragmented Process 1- Book A Reservation
2] Process 2: Change The Reservation (if there is any change from Customer)
Use Case Name: Change the reservationID: UC-2Priority: High
Actor: Receptionist/Manager
Description: Customer requests to change reservation, receptionist, manager checks new reservation availability
Trigger: Customer requests for reservation change Type: External Normal Course: Refer to fig 3, Change the reservation
InputsSource OutputsDestination
1.Customer name2.Address3.Credit card details4. No. Of persons5. New arrival and departure date
Electronic reservation of Bide-A-WhileReservation confirmation details such as reservation code, room no etc.Customer
2.Change The Reservation
Fig 3: Bide-A-While Electronic Reservation System Fragmented Process 2- Change The Reservation
3] Process 3: Generate The Bill
Use Case Name: Generate the billID: UC-3Priority: High
Actor: Receptionist/Manager
Description: Manager/Receptionist generates the bill for customer stay
Trigger: Bill generation initiated Type: Temporal Normal course: Refer to fig 4, Generate the bill
InputsSource OutputsDestination
Payment detailsCredit card,Net Banking
Electronic reservation of Bide-A-WhileBide-A-While ReceiptCustomer
Process 3: Generate The Bill
Fig 4: Bide-A-While Electronic Reservation System Fragmented Process 3 - Generate The Bill
Level 0 Data Flow Diagram:The Level 0 DFD shows how the system is divided into 'sub-systems' (processes), each of which deals with one or more of the data flows to or from an external agent, and which together provide all of the functionality of the system as a whole.
Fig 5: Bide-A-While Electronic Reservation System Level 0 Data Flow Diagram
Limitations of Data Flow Diagrams DFD are time consuming where analysts have to be in wait until entire process is represented by management. Physical considerations are not accounted in DFD.
References:1. Systems Analysis and Design - Dennis. Wixom. Roth2. http://en.wikipedia.org/wiki/System_context_diagram