Yazar "Çokal, Cahit" için listeleme
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Algebraic break of a cryptosystem based on discretized two-dimensional chaotic maps
Solak, Ercan; Çokal, Cahit (Elsevier Science BV, 2009-03-30)Recently, a cryptosystem based on two-dimensional discretized chaotic maps was proposed [T. Xiang, et al., Phys. Lett. A 364 (2007) 252]. In this Letter, we cryptanalyze the proposal using algebraic methods. We give three ... -
Algebraic break of image ciphers based on discretized chaotic map lattices
Solak, Ercan; Çokal, Cahit (Elsevier Science Inc, 2011-01-01)In this paper, we provide an algebraic cryptanalysis of a recently proposed chaotic image cipher. We show that the secret parameters of the algorithm can be revealed using chosen-plaintext attacks. Our attack uses the orbit ... -
Comment on "Encryption and decryption of images with chaotic map lattices" [Chaos 16, 033118 (2006)]
Solak, Ercan; Çokal, Cahit (American Institute of Physics Inc., 2008-09)In this paper, we comment on the chaotic encryption algorithm proposed by A. N. Pisarchik et al. [Chaos 16, 033118 (2006)]. We demonstrate that the algorithm is not invertible. We suggest simple modifications that can ... -
Cryptanalysis of a chaos-based image encryption algorithm
Çokal, Cahit; Solak, Ercan (Elsevier Science BV, 2009-03-30)A chaos-based image encryption algorithm was proposed in [Z.-H. Guan, F. Huang, W. Guan, Phys. Lett. A 346 (2005) 153]. In this Letter, we analyze the security weaknesses of the proposal. By applying chosen-plaintext and ... -
Cryptanalysis of a cryptosystem based on discretized two-dimensional chaotic maps
Solak, Ercan; Çokal, Cahit (Elsevier Science BV, 2008-11-17)Recently, an encryption algorithm based on two-dimensional discretized chaotic maps was proposed [Xiang et al., Phys. Lett. A 364 (2007) 252]. In this Letter, we analyze the security weaknesses of the proposal. Using the ... -
Cryptanalysis of Fridrich's chaotic image encryption
Solak, Ercan; Çokal, Cahit; Yıldız, Olcay Taner; Bıyıkoğlu, Türker (World Scientific Publishing, 2010-05)We cryptanalyze Fridrich's chaotic image encryption algorithm. We show that the algebraic weaknesses of the algorithm make it vulnerable against chosen-ciphertext attacks. We propose an attack that reveals the secret ... -
Security of chaotic cryptosystems
Çokal, Cahit (Işık Üniversitesi, 2008)In this thesis, we tried to show the weaknesses of chaotic cryptosystems. We break four chaos-based cryptosystems and proved our attacks. In our first cryptanalysis, we broke a cryptosystem based on two dimensional chaotic ...