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Lecture

Cryptanalysis: Public-Key

In course

COM-501: Advanced cryptography

This course reviews some failure cases in public-key cryptography. It introduces some cryptanalysis techniques. It also presents fundamentals in cryptography such as interactive proofs. Finally, it presents some techniques to validate the security of crypt ...

Description

This lecture covers cryptanalysis techniques related to public-key cryptography, focusing on RSA, Diffie-Hellman, and ElGamal. Topics include attacks on low exponents, power analysis, side-channel attacks, countermeasures, and various algorithms like Coppersmith, Wiener, and Pollard Rho. The instructor discusses the security models, signature schemes, and failure cases in cryptographic systems.

Instructor

Serge Vaudenay

Serge Vaudenay entered at the Ecole Normale Supérieure in 1989 with a major in mathematics. He earned his agrégation (secondary teaching degree) in mathematics in 1992, then a PhD in Computer Science at the University of Paris 7 - Denis Diderot in 1995. He subsequently became a senior research fellow at the CNRS, prior to being granted his habilitation à diriger des recherches (a postdoctoral degree authorizing the recipient to supervise doctoral students). In 1999, he was appointed as a Professor at the EPFL, where he created the Security and Cryptography Laboratory.

Official source

Ontological neighbourhood

Computer engineering

Computer security: Public-key cryptography

Related concepts (32)

Public-key cryptography

Public-key cryptography, or asymmetric cryptography, is the field of cryptographic systems that use pairs of related keys. Each key pair consists of a public key and a corresponding private key. Key pairs are generated with cryptographic algorithms based on mathematical problems termed one-way functions. Security of public-key cryptography depends on keeping the private key secret; the public key can be openly distributed without compromising security.

Cryptanalysis

Cryptanalysis (from the Greek kryptós, "hidden", and analýein, "to analyze") refers to the process of analyzing information systems in order to understand hidden aspects of the systems. Cryptanalysis is used to breach cryptographic security systems and gain access to the contents of encrypted messages, even if the cryptographic key is unknown. In addition to mathematical analysis of cryptographic algorithms, cryptanalysis includes the study of side-channel attacks that do not target weaknesses in the cryptographic algorithms themselves, but instead exploit weaknesses in their implementation.

Public key fingerprint

In public-key cryptography, a public key fingerprint is a short sequence of bytes used to identify a longer public key. Fingerprints are created by applying a cryptographic hash function to a public key. Since fingerprints are shorter than the keys they refer to, they can be used to simplify certain key management tasks. In Microsoft software, "thumbprint" is used instead of "fingerprint." A public key fingerprint is typically created through the following steps: A public key (and optionally some additional data) is encoded into a sequence of bytes.

Differential cryptanalysis

Differential cryptanalysis is a general form of cryptanalysis applicable primarily to block ciphers, but also to stream ciphers and cryptographic hash functions. In the broadest sense, it is the study of how differences in information input can affect the resultant difference at the output. In the case of a block cipher, it refers to a set of techniques for tracing differences through the network of transformation, discovering where the cipher exhibits non-random behavior, and exploiting such properties to recover the secret key (cryptography key).

Public key infrastructure

A public key infrastructure (PKI) is a set of roles, policies, hardware, software and procedures needed to create, manage, distribute, use, store and revoke digital certificates and manage public-key encryption. The purpose of a PKI is to facilitate the secure electronic transfer of information for a range of network activities such as e-commerce, internet banking and confidential email.

Related lectures (36)

Cryptographic Security Models

Explores Cryptographic Security Models, including Diffie-Hellman and ElGamal Security, RSA, and practical encryption problems.

Cryptanalysis: Public-Key & The Power of Interaction

Explores cryptanalysis in public-key systems and the power of interaction in interactive proofs, covering CO-NP, NP classes, P vs. NP, and more.

RSA Encryption: Principles and Applications

Explores RSA encryption principles, factorization challenges, and practical applications in data security.

Diffie-Hellman Cryptography: Key Exchange and ElGamal Encryption

Covers the Diffie-Hellman key exchange protocol and the ElGamal public-key cryptosystem.

Public-Key Cryptography: Fundamentals and Applications