Payment Security Learning Projects
Payment Security Learning Projects
This directory contains comprehensive, expanded project guides for learning credit card security and payment systems. Each project file provides deep theoretical foundations, complete specifications, solution architectures, implementation guides, and resources to enable independent learning.
Overview
Payment security sits at the intersection of cryptography, distributed systems, compliance, and real-world financial infrastructure. These projects progressively build your understanding from basic card validation to full payment ecosystem simulation.
Projects
| # | Project | Difficulty | Focus Area |
|---|---|---|---|
| P01 | Card Number Validator & BIN Intelligence Service | Beginner | Data Validation, PAN Structure |
| P02 | Payment Tokenization Vault | Intermediate | Cryptography, Token Architecture |
| P03 | Point-to-Point Encryption (P2PE) Simulator | Advanced | Key Management, HSM Concepts |
| P04 | 3D Secure Authentication Flow | Intermediate-Advanced | Protocol Design, Web Security |
| P05 | Mini Payment Gateway with PCI-Compliant Architecture | Advanced | Compliance, System Architecture |
| P06 | Full Payment Processing Simulator (Capstone) | Expert | Full Integration, Distributed Systems |
Recommended Learning Path
┌─────────────────────────────────────────────────────────────────────────┐
│ PAYMENT SECURITY LEARNING PATH │
├─────────────────────────────────────────────────────────────────────────┤
│ │
│ Week 1: Foundation │
│ ┌──────────────────────┐ │
│ │ P01: Card Validator │ ← Start here (weekend project) │
│ │ & BIN Service │ │
│ └──────────┬───────────┘ │
│ │ │
│ Week 2-3: Core Concept │
│ ▼ │
│ ┌──────────────────────┐ │
│ │ P02: Tokenization │ ← THE core concept in modern payments │
│ │ Vault │ │
│ └──────────┬───────────┘ │
│ │ │
│ Week 4-6: Specialization (choose one path) │
│ ├─────────────────────────┐ │
│ ▼ ▼ │
│ ┌──────────────────────┐ ┌──────────────────────┐ │
│ │ P03: P2PE Simulator │ │ P04: 3D Secure Flow │ │
│ │ (Card-Present) │ │ (E-Commerce) │ │
│ └──────────┬───────────┘ └──────────┬───────────┘ │
│ │ │ │
│ Week 7-10: Integration │ │
│ └─────────────┬───────────┘ │
│ ▼ │
│ ┌──────────────────────────────────────┐ │
│ │ P05: Mini Payment Gateway │ │
│ │ (PCI-Compliant Architecture) │ │
│ └──────────────────┬───────────────────┘ │
│ │ │
│ Month 3+: Mastery ▼ │
│ ┌──────────────────────────────────────┐ │
│ │ P06: Full Payment Processing │ ← Complete ecosystem │
│ │ Simulator (Capstone) │ │
│ └──────────────────────────────────────┘ │
│ │
└─────────────────────────────────────────────────────────────────────────┘
Core Concepts Covered
Data Classification & Protection
- Primary Account Number (PAN) handling
- Cardholder Data Environment (CDE) boundaries
- What data can be stored vs. what must never touch disk
Cryptographic Primitives in Payments
- Symmetric encryption (AES-256 for data at rest)
- Key hierarchy and derivation (DUKPT, TR-31)
- HSM operations and key ceremonies
- Digital signatures for transaction integrity
Tokenization Architecture
- Format-preserving tokenization
- Vault design and token-to-PAN mapping
- Token scoping (merchant, channel, device)
Transaction Flow Security
- Point-to-Point Encryption (P2PE)
- 3D Secure authentication
- Authorization vs. settlement
- EMV chip cryptograms
Compliance & Standards
- PCI DSS requirements (and why they exist)
- PA-DSS for payment applications
- PIN security (PCI PIN)
Essential Standards Reference
| Standard | What It Covers | Where to Get It |
|---|---|---|
| PCI DSS v4.0 | Overall card data security | pcisecuritystandards.org |
| PA-DSS | Payment application security | pcisecuritystandards.org |
| PCI PIN | PIN entry device security | pcisecuritystandards.org |
| EMV | Chip card specifications | emvco.com |
| 3D Secure 2.x | Online authentication | emvco.com |
| ISO 8583 | Transaction message format | ISO store |
| ANSI X9.24 | DUKPT key management | ANSI store |
| NIST SP 800-38G | Format-preserving encryption | nist.gov |
Prerequisites
Before starting these projects, ensure you have:
- Programming: Proficiency in C (for projects 1-3, 6), understanding of web development (for project 4)
- Cryptography Basics: Understanding of symmetric vs asymmetric encryption, hashing
- Networking: Basic TCP/IP, HTTP/HTTPS concepts
- Database: SQL fundamentals, understanding of data modeling
Resources
Primary Books
- “Serious Cryptography, 2nd Edition” by Jean-Philippe Aumasson
- “Security in Computing” by Charles Pfleeger
- “Designing Data-Intensive Applications” by Martin Kleppmann
- “Foundations of Information Security” by Jason Andress
- “PCI DSS: An Integrated Data Security Standard Guide” by Jim Seaman
Free Documentation
- PCI DSS v4.0 (pcisecuritystandards.org)
- EMVCo 3D Secure Specification (emvco.com)
- NIST SP 800-38G (nist.gov)