Cryptography basics: Quantum Systems

This lecture covers the fundamentals of cryptography, including how it works, its applications, types, flaws, and the importance of having a background for advanced courses. Topics include encryption, decryption, confidentiality, error detection, error correction, hash functions, signatures, authentication, and the challenges of sharing secrets securely. It also delves into the concepts of encoding, data integrity, error detection through metadata, and the use of checksums. The lecture explores symmetric and asymmetric encryption, digital signatures, key management, and the vulnerabilities associated with different encryption techniques. Additionally, it discusses the role of Certificate Authorities, encryption in transit, at rest, and in process, as well as the impact of quantum computing on current cryptographic systems.