Payment handling in LLD - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the primary goal of a payment handling system?

To securely process financial transactions between a payer and a payee, ensuring accuracy, reliability, and compliance with regulations.

beginner

Name two common components of a payment handling system.

1. Payment Gateway: Interfaces with banks and payment networks.<br>2. Transaction Processor: Validates and records transactions.

intermediate

Why is idempotency important in payment processing?

It prevents duplicate charges by ensuring that repeated requests with the same identifier are processed only once.

beginner

Explain the role of a payment gateway in simple terms.

It acts like a secure messenger that sends payment details from the customer to the bank and returns the approval or rejection.

intermediate

What are common security measures in payment handling systems?

Encryption of data, PCI DSS compliance, tokenization of card details, and secure authentication methods.

What does idempotency ensure in payment processing?

A Prevents duplicate transactions

B Speeds up payment processing

C Encrypts payment data

D Authenticates users

Idempotency ensures that repeated requests with the same identifier do not cause duplicate charges.

Which component acts as a secure messenger between customer and bank?

A Transaction Processor

B Database

C Load Balancer

D Payment Gateway

The payment gateway securely sends payment details to the bank and returns the response.

Which security standard is commonly followed in payment systems?

A PCI DSS

B ISO 9001

C HIPAA

D GDPR

PCI DSS is the Payment Card Industry Data Security Standard for protecting card data.

What is tokenization in payment handling?

A Logging transaction history

B Encrypting data with a key

C Replacing sensitive data with a non-sensitive equivalent

D Authenticating user identity

Tokenization replaces sensitive card details with tokens to reduce risk.

Which of these is NOT a typical step in payment processing?

A Settlement

B Compilation

C Authorization

D Capture

Compilation is unrelated; authorization, capture, and settlement are key steps.

Describe the flow of a payment transaction from customer to bank and back.

Think of the payment gateway as a secure messenger.

List and explain key security practices in payment handling systems.

Focus on protecting sensitive payment information.