Question

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.

Short answer

Develop use cases for withdrawing cash, depositing funds, checking balance, transferring funds, and changing PIN.

Step-by-step solution

Identify the Primary Actor

The primary actor for an ATM system is the bank customer who uses the ATM to perform various transactions like withdrawing cash, depositing money, checking balances, etc.

Define Use Case: Withdraw Cash

The customer inserts their ATM card into the machine, inputs their PIN, selects the option to withdraw cash, chooses an account and amount, and then receives the cash and a receipt.

Define Use Case: Deposit Funds

The customer inserts their ATM card, inputs their PIN, selects the option to deposit funds, chooses the account type, inserts cash or checks into the machine, and receives confirmation via receipt.

Define Use Case: Check Balance

The customer inserts their card, enters their PIN, selects the option to view balance, chooses the account to check, and views the balance on the screen. They can then choose to print a receipt.

Define Use Case: Transfer Funds

The customer logs into the ATM with their card and PIN, selects the transfer option, chooses the accounts from which to transfer and to which to transfer, enters the amount, and receives confirmation.

Define Use Case: Change PIN

The customer enters their card and PIN, selects the option to change PIN, enters the current PIN, and inputs the new PIN twice to confirm. They receive confirmation of the change.

Consolidate Use Cases

Compile the identified use cases to serve as a comprehensive basis for understanding the ATM system requirements, ensuring each covers various aspects of ATM operations.

Key concepts

Use Case Development

When developing a system like an ATM, it's crucial to start with use case development. This process helps in understanding the actual functional requirements based on how the system will be used by the actors involved, primarily the bank customers. A use case details a specific way the system is expected to interact with its users, focusing on achieving a goal.

In practical terms, a use case defines scenarios such as withdrawing cash, depositing funds, checking balances, transferring funds, and changing a PIN. Here's a simple way to visualize it:

• **Withdraw Cash**: The customer inserts their card, inputs a PIN, selects withdraw, chooses an account and amount, and the ATM dispenses cash.
• **Deposit Funds**: Similar steps as withdrawing cash but choosing a deposit option, inserting cash or checks instead of receiving them.
• **Check Balance**: This involves accessing the account to view balance details, either on-screen or printed.
• **Transfer Funds**: Selecting the accounts for debiting and crediting within the ATM system and confirming the transaction.
• **Change PIN**: This use case involves security features where the customer changes their account access code.

By systematically developing these use cases, developers ensure that the ATM system covers all necessary functionalities for user interaction.

System Analysis

System Analysis in the scope of an ATM involves evaluating how each use case translates into specific system requirements. For an ATM system, each use case represents a series of interactions and data flows that need to be meticulously analyzed to ensure the system can process these activities efficiently.

The analysis helps in identifying key requirements, such as:

• System interfaces and user inputs for each transaction type
• Data security measures for sensitive operations (like PIN changes and fund transfers)
• Transaction processing capabilities to handle real-time data exchanges
• Error handling mechanisms for scenarios like incorrect PIN entry or network failure
• Hardware specifications for components like card readers and cash dispensers

This systematic study ensures the system is not only functional but also secure, reliable, and user-friendly. By analyzing system needs alongside use cases, developers can identify potential bottlenecks and streamline system architecture accordingly.

User Interaction with ATM

User interaction with an ATM is a crucial aspect that determines the usability and success of the system. It's the interface through which the customer engages with the ATM to complete various transactions. Understanding this interaction involves designing intuitive and straightforward user interfaces that guide the customer from start to finish efficiently.

Essential elements of ATM user interaction include:

• **Simple User Interface (UI)**: Ensuring that the UI is easy to navigate, with clear options for each task like withdrawing cash or checking balances.
• **Security Protocols**: These involve processes such as verifying identity through card use and PIN entry.
• **Feedback and Confirmation**: Systems to ensure users are informed about successful transactions or errors, often through screen messages or printed receipts.
• **Error Recovery Options**: Allowing users to easily correct mistakes without restarting the transaction process.

By focusing on these aspects, developers enhance customer satisfaction and ensure secure, efficient user interaction with the ATM system.