Assignment

1. Produce a high level design from the DFD obtained in Exercise 1.

Exercise 1

Given the following for a web based order processing system for a computer store: A new user can connect to the company's web page and create a new customer profile by providing personal information. This information is validated and saved in a customer information file on the company's server. The user is then provided with a user ID and password via an email sent by the system. Using the provided password, the user can then logon to thesystem andplace an order. The user can also delete or update an order within a certain amount of time after placing the order. In all cases, the system verifies the transaction and acts accordingly. If the transaction is not allowed (e.g., deleting after the deadline),the user is informed. Before accepting the transaction, the system checks the customer information file for the credit check and the inventory file for availability. If the order item is not available, the system asks the user whether to keep the order in a back order file, if not, the order is discarded. If the product is available, the inventory and customer information files are updated accordingly. The ordered product is delivered along with a bill and the accounting file is updated. Once the payment is received, the accounting file and the customer information files are updated accordingly. From time to time, the system administrator sends emails to customers informing them of special deals. Draw DFDs s at all levels. Produce an OOA model.

Exercise 2

Consider a software system that help manage taking senior citizen patients to care facility. The system contains patients, drivers, facilities. Drivers will use their own Vehicle. Vehicle must be registered. A driver can register more than one vehicle. The driver gets paid based on the trip at a defined rate. A patient requests for a ride. The closest ready vehicle is chosen to service that ride.

The system must be able to be used on smart devices and online. A patient needs to register, before being able to use the system.

Drivers also need to register before being able to server rides. There are drivers registered in the system. A ride starts when the driver picks up the patient.

The ride ends when the driver reached the site of the facility. Drivers get rating from patients. Drivers' rate get adjusted based on their ratings. A patient can browse for possible drivers in a vicinity of 5 miles. A patient can decide to pick a specific driver or accept the one chosen by the system if available. The system has employees to review and validate registration. Employees can be manager or staff.

1. Create a context level (System level) DFD diagram for the case study. (Refer to the first case study assignment).

2. Create a level 0 DFD for the context level created in 1.

3. Create a decomposition of the process "Service a ride".