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RCCA Security
Replayable CCA security (RCCA security) is a security notion in cryptography that relaxes the older notion of Security against Chosen-Ciphertext Attack (CCA, more precisely ''adaptive'' security notion CCA2): all CCA-secure systems are RCCA secure but the converse is not true. The claim is that for a lot of use cases, CCA is too strong and RCCA suffices.Ran Canetti, Hugo Krawczyk, Jesper B. Nielsen, ''Relaxing Chosen-Ciphertext Security''. 2003 eprint archiv/ref> Nowadays a certain amount of cryptographic scheme are proved RCCA-secure instead of CCA secure. It was introduced in 2003 in a research publication by Ran Canetti Ran Canetti (Hebrew: רן קנטי) is a professor of Computer Science at Boston University. and the director of the Check Point Institute for Information Security and of the Center for Reliable Information System and Cyber Security. He is also ..., Hugo Krawczyk and Jesper B. Nielsen. References Cryptography {{crypto-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptography
Cryptography, or cryptology (from grc, , translit=kryptós "hidden, secret"; and ''graphein'', "to write", or ''-logia'', "study", respectively), is the practice and study of techniques for secure communication in the presence of adversarial behavior. More generally, cryptography is about constructing and analyzing protocols that prevent third parties or the public from reading private messages. Modern cryptography exists at the intersection of the disciplines of mathematics, computer science, information security, electrical engineering, digital signal processing, physics, and others. Core concepts related to information security (data confidentiality, data integrity, authentication, and non-repudiation) are also central to cryptography. Practical applications of cryptography include electronic commerce, chip-based payment cards, digital currencies, computer passwords, and military communications. Cryptography prior to the modern age was effectively synony ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chosen-ciphertext Attack
A chosen-ciphertext attack (CCA) is an attack model for cryptanalysis where the cryptanalyst can gather information by obtaining the decryptions of chosen ciphertexts. From these pieces of information the adversary can attempt to recover the hidden secret key used for decryption. For formal definitions of security against chosen-ciphertext attacks, see for example: Michael Luby and Mihir Bellare et al. Introduction A number of otherwise secure schemes can be defeated under chosen-ciphertext attack. For example, the El Gamal cryptosystem is semantically secure under chosen-plaintext attack, but this semantic security can be trivially defeated under a chosen-ciphertext attack. Early versions of RSA padding used in the SSL protocol were vulnerable to a sophisticated adaptive chosen-ciphertext attack which revealed SSL session keys. Chosen-ciphertext attacks have implications for some self-synchronizing stream ciphers as well. Designers of tamper-resistant cryptographic smart ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adaptive Chosen-ciphertext Attack
An adaptive chosen-ciphertext attack (abbreviated as CCA2) is an interactive form of chosen-ciphertext attack in which an attacker first sends a number of ciphertexts to be decrypted chosen adaptively, and then uses the results to distinguish a target ciphertext without consulting the oracle on the challenge ciphertext. In an adaptive attack, the attacker is further allowed adaptive queries to be asked after the target is revealed (but the target query is disallowed). It is extending the indifferent (non-adaptive) chosen-ciphertext attack (CCA1) where the second stage of adaptive queries is not allowed. Charles Rackoff and Dan Simon defined CCA2 and suggested a system building on the non-adaptive CCA1 definition and system of Moni Naor and Moti Yung (which was the first treatment of chosen ciphertext attack immunity of public key systems). In certain practical settings, the goal of this attack is to gradually reveal information about an encrypted message, or about the decrypti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ran Canetti
Ran Canetti (Hebrew: רן קנטי) is a professor of Computer Science at Boston University. and the director of the Check Point Institute for Information Security and of the Center for Reliable Information System and Cyber Security. He is also associate editor of the Journal of Cryptology and Information and Computation. His main areas of research span cryptography and information security, with an emphasis on the design, analysis and use of cryptographic protocols. Biography Born in 1962 in Tel Aviv, Israel, Canetti obtained his BA in Computer Science in 1989, his BA in Physics in 1990, and his M.Sc in Computer Science in 1991, all from the Technion, Haifa. He received his PhD in 1995 from the Weizmann Institute, Rehovot under the supervision of Prof. Oded Goldreich. He then completed his post-doctoral training at the Lab of Computer Science, at the Massachusetts Institute of Technology (MIT) in 1996 under the supervision of Prof. Shafi Goldwasser. He then joined IBM’s T. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
