17 research outputs found
Performance analysis of Jakimoski-Kocarev attack on a class of chaotic cryptosystems
No full textRecently G. Jakimoski and L. Kocarev cryptanalzed two chaotic cryptosystems without using chaotic synchronization – Baptista cryptosystem and Alvarez cryptosystem. As a result, they pointed out that neither of the two cryptosystems are secure to known-plaintext attacks. In this letter, we re-study the performance of Jakimoski-Kocarev attack on Baptista cryptosystem and find that it is not efficient enough as a practical attack tool. Furthermore, a simple but effective remedy is presented to resist Jakimoski-Kocarev attack, and the detailed discussion on its performance are given. Key words: chaotic encryption system; cryptanalysis; cryptography
Performance analysis of Jakimoski-Kocarev attack on a class of chaotic cryptosystems
No full textRecently G. Jakimoski and L. Kocarev cryptanalzed two chaotic cryptosystems without using chaotic synchronization -- Baptista cryptosystem and Alvarez cryptosystem. As a result, they pointed out that neither of the two cryptosystems are secure to known-plaintext attacks. In this letter, we re-study the performance of Jakimoski-Kocarev attack on Baptista cryptosystem and find that it is not e#cient enough as a practical attack tool. Furthermore, a simple but e#ective remedy is presented to resist Jakimoski-Kocarev attack, and the detailed discussion on its performance are given
SPECIFICITIES IN THE APPLICATION OF EU RIGHTS
No full textViolation of EU competition law results in harm to various parties, including direct competitors, customers, and end-users of services. The issue of compensation for damages in the EU arose alongside efforts to address the democratic deficit and institutionalize the EC/EU, emphasizing protecting individuals’ subjective rights before national courts. This raises questions about whether the Treaty on the Functioning of the European Union (TFEU) establishes subjective rights for individuals to seek protection before national courts. Articles 101 and 102 of the TFEU regulate restrictive agreements and dominant market positions, prohibiting restrictive agreements and sanctioning abuse of dominance. However, preventing restrictive agreements entirely is impractical, leading to the recognition of the right to compensation as an inherent subjective right. This recognition, stemming from the dual nature of EU law, is supported by principles such as direct effect and effectiveness, serving as a basis for establishing procedural autonomy in judicial protection. The author analyzes these issues in three parts: general considerations, the nature of the right to compensation for damage, and procedures for enforcing this right. The paper argues that public and private enforcement of EU competition law are complementary and advocates for implementing compensation for damages not only through individual lawsuits but also by introducing collective redress mechanisms to protect collective interests
ASC-1:An Authenticated Encryption Stream Cipher
No full textThe goal of the modes of operation for authenticated encryption is to achieve faster encryption and message authentication by performing both the encryption and the message authentication in a single pass as opposed to the traditional encrypt-then-mac approach, which requires two passes. Unfortunately, the use of a block cipher as a building block limits the performance of the authenticated encryption schemes to at most one message block per block cipher evaluation.In this paper, we propose the authenticated encryption scheme ASC-1 (Authenticating Stream Cipher One). Similarly to LEX, ASC-1 uses leak extraction from diÆerent AES rounds to compute the key material that is XOR-ed with the message to compute the ciphertext. Unlike LEX, the ASC-1 operates in a CFB fashion to compute an authentication tag over the encrypted message. We argue that ASC-1 is secure by reducingits (IND-CCA , INT-CTXT) security to the problem of distinguishing the case when the round keys are uniformly random from the case when the round keys are generated by a key scheduling algorithm
Threshold Ring Signatures Efficient for Large Sets of Signers
No full textThe anonymity provided by the threshold ring signature scheme proposed by Bresson et al (Crypto'02) is perfect. However, its complexity is prohibitively large even for relatively small sets of signers. We propose use of threshold schemes based on covering designs that are efficient for large groups of signers. The cost we pay is non-perfect anonymity
