Homework 6 – Software Engineering – CSCI 362-001

4.5– Using the technique suggested here, where natural language descriptions are presented in a standard format, write plausible user requirements for the following functions:

An unattended petrol (gas) pump system that includes a credit card reader. The customer swipes the card through the reader then specifies the amount of fuel required. The fuel is delivered and the customer’s account debited.

The petrol pump system shall dispense the amount of fuel specified after ensuring that the bank has approved the withdrawal.

The cash-dispensing function in a bank ATM.

The ATM shall dispense the amount of cash specified after ensuring that the bank has approved the withdrawal.

The spelling-check and correcting function in a word processor.

The spell-check function should underline all words it does not recognize and allow users to right click and view spelling suggestions.

4.6 – Suggest how an engineer responsible for drawing up a system requirements specification might keep track of the relationships between functional and non-functional requirements.

Functional requirements used to enforce non-functional requirements could be recorded and tracked by having a diagram with functional requirements connected to non-functional requirements by lines.

4.7– Using your knowledge of how an ATM is used, develop a set of use cases that could serve as a basis for understanding the requirements for an ATM system.

Withdrawing money allows one user to withdraw money from their account. The user inserts their debit card, verifies their identity via PIN, and specifies how much money they would like to withdraw. The system deducts that amount from their account if the machine has enough to dispense, and does so. The transaction would close and the card would be returned.

Depositing money allows one user to deposit money into their account. The user inserts their debit card, verifies their identity via PIN, and specifies an amount to deposit. They then select what form the amount will be deposited be – cash or check. The check or cash would then be collected and verified as being the correct amount and legal, and the transaction would close. The card would be returned.