This course introduces participants to the evolving field of post-quantum cryptography (PQC), a response to the security threats posed by quantum computers. You’ll review the principles of modern cryptography, understand the impact of quantum algorithms like Shor’s and Grover’s, and explore how new cryptographic schemes are being developed to withstand these threats.

The course emphasizes practical skills through hands-on activities. Participants will simulate quantum attacks on traditional cryptography using Qiskit, then experiment with post-quantum cryptographic tools to see how they provide protection.

Session 1: Classical Cryptography in a Quantum World

• Quick recap: What is cryptography, and what are its goals (confidentiality, integrity, authenticity)
• How classical cryptographic systems work (i.e., RSA encryption)
• Threats from quantum computing: Shor’s and Grover’s algorithms (conceptual overview)
• Real-world implications: which systems are vulnerable and why
• Hands-on: Try a classical RSA encryption/decryption flow and visualize the attack potential

Session 2: Quantum Attacks in Action

• Walkthrough of a simplified version of Shor’s algorithm using Qiskit
• Simulating a quantum factorization attack on a toy RSA key
• Understanding limitations of current quantum attacks (e.g., qubit requirements)
• Hands-on: Qiskit exercise, attack demo with visualization of result and failure of classical cryptography

Session 3: Post-Quantum Cryptography Approaches

• Overview of NIST's PQC standardization project and categories:
• Lattice-based (e.g., Kyber, Dilithium)
• Code-based
• Hash-based signatures
• Comparison: performance, key sizes, and use cases
• Hands-on: Use open-source libraries (e.g., pqcrypto, liboqs, or PyCryptodome with PQC support) to encrypt/decrypt using PQC schemes
• Real-world example: secure messaging or file encryption with PQC

Session 4: Defense in Practice – Building Resilient Systems

• Defending classical cryptosystems using hybrid and PQC methods
• Case study: Replacing RSA with Kyber in a simple protocol
• Hands-on: Simulate quantum attack + PQC defense in parallel
• Future of cryptography: migration paths, readiness, and risks
• Final exercise: Secure a mini “chat” or “file transfer” system with PQC
• Wrap-up & next steps (resources, tools)

By the end of this course, participants will be able to:

• Explain the security risks posed by quantum computing to classical cryptography
• Simulate quantum attacks using Qiskit on simplified cryptographic systems
• Describe the leading post-quantum cryptographic techniques and how they work
• Use PQC libraries to encrypt, decrypt, and verify secure communications
• Apply PQC in practical scenarios to secure data and communication

This course combines conceptual grounding with extensive hands-on learning. Participants will use both Qiskit and post-quantum crypto libraries to simulate attacks and test countermeasures. Each session includes guided coding exercises and short real world demos. The course uses interactive notebooks, command-line tools, and visualization platforms to bridge theory with practice. Participants are encouraged to modify and experiment with code examples to deepen their understanding.