Context: Apple has recently launched the PQ3 encryption model for its messaging app.
About PQ3:
- It is a post-quantum cryptographic model to encrypt the messages.
- It is designed to protect classical operating systems against quantum enabled cyber-attacks.
Classical cryptography
- Classical computers employ classical cryptography strategies such as RSA, Elliptic Curve signatures, Diffie-Hellman key exchange to establish secure end-to-end encrypted connections between devices.
- These algorithms are based on difficult mathematical problems which are difficult to crack by classical computers. However, the rise of quantum computers can solve these mathematical problems.
- To mitigate these risks to information security from future quantum computers, researchers have been developing post-quantum cryptography.
What is Post-Quantum Cryptography
- Post-quantum cryptography, also known as quantum encryption, is the development of cryptographic systems for classical computers that can prevent attacks launched by quantum computers.
- These are new public key algorithms that provide building blocks for quantum-secure protocols but don’t require a quantum computer to run.
- It is different from quantum key distribution (QKD) in the sense that QKD allows a secret cryptographic key to be shared between two remote parties in such a way that key interception can be easily detected.
- Shor's Algorithm, named after mathematician Peter Shor, is a quantum algorithm designed to efficiently factorize large composite numbers. It's one of the most famous and impactful algorithms in quantum computing, as it provides an exponential speedup over the best-known classical algorithms for factoring.
- Shor's Algorithm can factor a composite number in polynomial time, compared to the exponential time required by classical algorithms.
- Shor's Algorithm represents a landmark achievement in quantum computing, showcasing the potential of quantum algorithms to solve problems previously considered intractable. Its discovery has had a profound impact on both the theoretical and practical aspects of quantum computing and cryptography, inspiring further research into quantum algorithms, complexity theory, and the development of quantum-resistant cryptographic protocols.