San Ling

Yeow Meng Chee, Tao Feng, San Ling, Huaxiong Wang, Liang Feng Zhang: Query-Efficient Locally Decodable Codes of Subexponential Length. Computational Complexity 22(1): 159-189 (2013)

Cunsheng Ding, San Ling: A q-polynomial approach to cyclic codes. Finite Fields and Their Applications 20: 1-14 (2013)

Somphong Jitman, San Ling, Hongwei Liu, Xiaoli Xie: Abelian Codes in Principal Ideal Group Algebras. IEEE Transactions on Information Theory 59(5): 3046-3058 (2013)

Cheng Chen, Jie Chen, Hoon Wei Lim, Zhenfeng Zhang, Dengguo Feng, San Ling, Huaxiong Wang: Fully Secure Attribute-Based Systems with Short Ciphertexts/Signatures and Threshold Access Structures. CT-RSA 2013: 50-67

San Ling, Khoa Nguyen, Damien Stehlé, Huaxiong Wang: Improved Zero-Knowledge Proofs of Knowledge for the ISIS Problem, and Applications. Public Key Cryptography 2013: 107-124

Yeow Meng Chee, San Ling, Huaxiong Wang, Liang Feng Zhang: Upper Bounds on Matching Families in $\mathbb{Z}_{pq}^n$. CoRR abs/1301.0980 (2013)

Yun Fan, San Ling, Hongwei Liu: Homogeneous Weights of Matrix Product Codes over Finite Principal Ideal Rings. CoRR abs/1304.1405 (2013)

Han Mao Kiah, Ka Hin Leung, San Ling: A note on cyclic codes over GR(p 2, m) of length p k. Des. Codes Cryptography 63(1): 105-112 (2012)

San Ling, Longjiang Qu: A note on linearized polynomials and the dimension of their kernels. Finite Fields and Their Applications 18(1): 56-62 (2012)

San Ling, Igor Shparlinski, Ron Steinfeld, Huaxiong Wang: On the modular inversion hidden number problem. J. Symb. Comput. 47(4): 358-367 (2012)

Yeow Meng Chee, San Ling, Yin Tan, Xiande Zhang: Universal cycles for minimum coverings of pairs by triples, with application to 2-radius sequences. Math. Comput. 81(277) (2012)

San Ling, Enver Ozdemir, Chaoping Xing: Constructing irreducible polynomials over finite fields. Math. Comput. 81(279) (2012)

Zhifang Zhang, Yeow Meng Chee, San Ling, Mulan Liu, Huaxiong Wang: Threshold changeable secret sharing schemes revisited. Theor. Comput. Sci. 418: 106-115 (2012)

Jie Chen, Hoon Wei Lim, San Ling, Huaxiong Wang, Khoa Nguyen: Revocable Identity-Based Encryption from Lattices. ACISP 2012: 390-403

Hongjun Wu, Tao Huang, Phuong Ha Nguyen, Huaxiong Wang, San Ling: Differential Attacks against Stream Cipher ZUC. ASIACRYPT 2012: 262-277

Lei Wei, Thomas Peyrin, Przemyslaw Sokolowski, San Ling, Josef Pieprzyk, Huaxiong Wang: On the (In)Security of IDEA in Various Hashing Modes. FSE 2012: 163-179

Chien-Ning Chen, Nisha Jacob, Sebastian Kutzner, San Ling, Axel Poschmann, Sirote Saetang: Standardized Signature Algorithms on Ultra-constrained 4-Bit MCU. IWSEC 2012: 37-50

Jie Chen, Hoon Wei Lim, San Ling, Huaxiong Wang, Hoeteck Wee: Shorter IBE and Signatures via Asymmetric Pairings. Pairing 2012: 122-140

Ron Steinfeld, San Ling, Josef Pieprzyk, Christophe Tartary, Huaxiong Wang: NTRUCCA: How to Strengthen NTRUEncrypt to Chosen-Ciphertext Security in the Standard Model. Public Key Cryptography 2012: 353-371

Nisha Jacob, Sirote Saetang, Chien-Ning Chen, Sebastian Kutzner, San Ling, Axel Poschmann: Feasibility and Practicability of Standardized Cryptography on 4-bit Micro Controllers. Selected Areas in Cryptography 2012: 184-201

Martianus Frederic Ezerman, Somphong Jitman, San Ling, Dmitrii V. Pasechnik: CSS-like Constructions of Asymmetric Quantum Codes. CoRR abs/1207.6512 (2012)

Jie Chen, Hoon Wei Lim, San Ling, Le Su, Huaxiong Wang: Anonymous and Adaptively Secure Revocable IBE with Constant Size Public Parameters. CoRR abs/1210.6441 (2012)

Yun Fan, San Ling, Hongwei Liu, Jing Shen, Chaoping Xing: Cumulative Distance Enumerators of Random Codes and their Thresholds. CoRR abs/1212.5679 (2012)

San Ling, Damien Stehlé: A Lattice-Based Traitor Tracing Scheme. IACR Cryptology ePrint Archive 2012: 88 (2012)

Jie Chen, Hoon Wei Lim, San Ling, Huaxiong Wang, Hoeteck Wee: Shorter IBE and Signatures via Asymmetric Pairings. IACR Cryptology ePrint Archive 2012: 224 (2012)

Lei Wei, Thomas Peyrin, Przemyslaw Sokolowski, San Ling, Josef Pieprzyk, Huaxiong Wang: On the (In)Security of IDEA in Various Hashing Modes. IACR Cryptology ePrint Archive 2012: 264 (2012)

Yi Deng, Juan A. Garay, San Ling, Huaxiong Wang, Moti Yung: On the (Im)Plausibility of Constant-Round Public-Coin Straight-Line-Simulatable Zero-Knowledge Proofs. IACR Cryptology ePrint Archive 2012: 508 (2012)

San Ling, Khoa Nguyen, Damien Stehlé, Huaxiong Wang: Improved Zero-knowledge Proofs of Knowledge for the ISIS Problem, and Applications. IACR Cryptology ePrint Archive 2012: 569 (2012)

Alexander Pott, Yin Tan, Tao Feng, San Ling: Association schemes arising from bent functions. Des. Codes Cryptography 59(1-3): 319-331 (2011)

Yeow Meng Chee, Gennian Ge, Lijun Ji, San Ling, Jianxing Yin: List decodability at small radii. Des. Codes Cryptography 61(2): 151-166 (2011)

Axel Poschmann, Amir Moradi, Khoongming Khoo, Chu-Wee Lim, Huaxiong Wang, San Ling: Side-Channel Resistant Crypto for Less than 2, 300 GE. J. Cryptology 24(2): 322-345 (2011)

Yan Jia, San Ling, Chaoping Xing: On Self-Dual Cyclic Codes Over Finite Fields. IEEE Transactions on Information Theory 57(4): 2243-2251 (2011)

Martianus Frederic Ezerman, San Ling, Patrick Solé: Additive Asymmetric Quantum Codes. IEEE Transactions on Information Theory 57(8): 5536-5550 (2011)

Christophe Tartary, Huaxiong Wang, San Ling: Authentication of Digital Streams. IEEE Transactions on Information Theory 57(9): 6285-6303 (2011)

Lei Wei, Christian Rechberger, Jian Guo, Hongjun Wu, Huaxiong Wang, San Ling: Improved Meet-in-the-Middle Cryptanalysis of KTANTAN (Poster). ACISP 2011: 433-438

Amir Moradi, Axel Poschmann, San Ling, Christof Paar, Huaxiong Wang: Pushing the Limits: A Very Compact and a Threshold Implementation of AES. EUROCRYPT 2011: 69-88

Yeow Meng Chee, Zhenbo Guo, San Ling, Fengjing Shao, Yuansheng Tang, Huaxiong Wang, Chaoping Xing (Eds.): Coding and Cryptology - Third International Workshop, IWCC 2011, Qingdao, China, May 30-June 3, 2011. Proceedings. Lecture Notes in Computer Science 6639, Springer 2011, isbn 978-3-642-20900-0

Lei Wei, Christian Rechberger, Jian Guo, Hongjun Wu, Huaxiong Wang, San Ling: Improved Meet-in-the-Middle Cryptanalysis of KTANTAN. IACR Cryptology ePrint Archive 2011: 201 (2011)

Jie Chen, Hoon Wei Lim, San Ling, Huaxiong Wang: The Relation and Transformation between Hierarchical Inner Product Encryption and Spatial Encryption. IACR Cryptology ePrint Archive 2011: 455 (2011)

Jie Chen, Hoon Wei Lim, San Ling, Huaxiong Wang, Khoa Nguyen: Revocable Identity-Based Encryption from Lattices. IACR Cryptology ePrint Archive 2011: 583 (2011)

Jie Chen, Hoon Wei Lim, San Ling, Huaxiong Wang: Fully Secure Spatial Encryption under Simple Assumptions with Constant-Size Ciphertexts. IACR Cryptology ePrint Archive 2011: 650 (2011)

Yeow Meng Chee, Son Hoang Dau, Alan C. H. Ling, San Ling: Linear size optimal q-ary constant-weight codes and constant-composition codes. IEEE Transactions on Information Theory 56(1): 140-151 (2010)

Long Wang, Keqin Feng, San Ling, Chaoping Xing: Asymmetric quantum codes: characterization and constructions. IEEE Transactions on Information Theory 56(6): 2938-2945 (2010)

San Ling, Jinquan Luo, Chaoping Xing: Generalization of Steane's enlargement construction of quantum codes and applications. IEEE Transactions on Information Theory 56(8): 4080-4084 (2010)

Lingfei Jin, San Ling, Jinquan Luo, Chaoping Xing: Application of classical hermitian self-orthogonal MDS codes to quantum MDS codes. IEEE Transactions on Information Theory 56(9): 4735-4740 (2010)

Phuong Ha Nguyen, Lei Wei, Huaxiong Wang, San Ling: On Multidimensional Linear Cryptanalysis. ACISP 2010: 37-52

Jian Guo, San Ling, Christian Rechberger, Huaxiong Wang: Advanced Meet-in-the-Middle Preimage Attacks: First Results on Full Tiger, and Improved Results on MD4 and SHA-2. ASIACRYPT 2010: 56-75

Axel Poschmann, San Ling, Huaxiong Wang: 256 Bit Standardized Crypto for 650 GE - GOST Revisited. CHES 2010: 219-233

Martianus Frederic Ezerman, San Ling, Patrick Solé: Additive Asymmetric Quantum Codes. CoRR abs/1002.4088 (2010)

Martianus Frederic Ezerman, San Ling, Patrick Solé, Olfa Yemen: From Skew-Cyclic Codes to Asymmetric Quantum Codes. CoRR abs/1005.0879 (2010)

Martianus Frederic Ezerman, Somphong Jitman, San Ling: On Asymmetric Quantum MDS Codes. CoRR abs/1006.1694 (2010)

Somphong Jitman, San Ling, Patanee Udomkavanich: Skew Constacyclic Codes over Finite Chain Rings. CoRR abs/1008.0327 (2010)

Yeow Meng Chee, San Ling, Yin Tan, Xiande Zhang: Universal Cycles for Minimum Coverings of Pairs by Triples, with Application to 2-Radius Sequences. CoRR abs/1008.1608 (2010)

Yeow Meng Chee, Son Hoang Dau, Alan C. H. Ling, San Ling: Linear Size Optimal q-ary Constant-Weight Codes and Constant-Composition Codes. CoRR abs/1008.1611 (2010)

Yeow Meng Chee, Tao Feng, San Ling, Huaxiong Wang, Liang Feng Zhang: Query-Efficient Locally Decodable Codes of Subexponential Length. CoRR abs/1008.1617 (2010)

Yeow Meng Chee, Gennian Ge, Lijun Ji, San Ling, Jianxing Yin: List Decodability at Small Radii. CoRR abs/1010.3312 (2010)

Somphong Jitman, San Ling, Hongwei Liu, Xiaoli Xie: Checkable Codes from Group Rings. CoRR abs/1012.5498 (2010)

Yeow Meng Chee, Tao Feng, San Ling, Huaxiong Wang, Liang Feng Zhang: Query-Efficient Locally Decodable Codes. Electronic Colloquium on Computational Complexity (ECCC) 17: 173 (2010)

Jian Guo, San Ling, Christian Rechberger, Huaxiong Wang: Advanced Meet-in-the-Middle Preimage Attacks: First Results on Full Tiger, and Improved Results on MD4 and SHA-2. IACR Cryptology ePrint Archive 2010: 16 (2010)

Chao Li, Qiang Li, San Ling: On the constructions of constant-composition codes from perfect nonlinear functions. Science in China Series F: Information Sciences 52(6): 964-973 (2009)

Chao Li, Qiang Li, San Ling: Properties and Applications of Preimage Distributions of Perfect Nonlinear Functions. IEEE Transactions on Information Theory 55(1): 64-69 (2009)

Chao Li, Longjiang Qu, San Ling: On the Covering Structures of Two Classes of Linear Codes From Perfect Nonlinear Functions. IEEE Transactions on Information Theory 55(1): 70-82 (2009)

Alex Biryukov, Praveen Gauravaram, Jian Guo, Dmitry Khovratovich, San Ling, Krystian Matusiewicz, Ivica Nikolic, Josef Pieprzyk, Huaxiong Wang: Cryptanalysis of the LAKE Hash Family. FSE 2009: 156-179

Hao Chen, San Ling, Carles Padró, Huaxiong Wang, Chaoping Xing: Key Predistribution Schemes and One-Time Broadcast Encryption Schemes from Algebraic Geometry Codes. IMA Int. Conf. 2009: 263-277

Jian Guo, Krystian Matusiewicz, Lars R. Knudsen, San Ling, Huaxiong Wang: Practical Pseudo-collisions for Hash Functions ARIRANG-224/384. Selected Areas in Cryptography 2009: 141-156

Yeow Meng Chee, Chao Li, San Ling, Huaxiong Wang, Chaoping Xing (Eds.): Coding and Cryptology, Second International Workshop, IWCC 2009, Zhangjiajie, China, June 1-5, 2009. Proceedings. Lecture Notes in Computer Science 5557, Springer 2009, isbn 978-3-642-01813-8

Jinquan Luo, San Ling, Chaoping Xing: Cyclic Codes and Sequences from a Class of Dembowski-Ostrom Functions. CoRR abs/0902.4509 (2009)

Jinquan Luo, San Ling, Chaoping Xing: Cyclic Codes and Sequences from Kasami-Welch Functions. CoRR abs/0902.4511 (2009)

Jian Guo, Krystian Matusiewicz, Lars R. Knudsen, San Ling, Huaxiong Wang: Practical pseudo-collisions for hash functions ARIRANG-224/384. IACR Cryptology ePrint Archive 2009: 197 (2009)

San Ling, Ferruh Özbudak: Some constructions of (t, m, s)-nets with improved parameters. Finite Fields and Their Applications 14(3): 658-675 (2008)

Han Mao Kiah, Ka Hin Leung, San Ling: Cyclic codes over GR(p², m) of length p^k. Finite Fields and Their Applications 14(3): 834-846 (2008)

Liqun Pu, Hao Shen, Jun Ma, San Ling: Cycle Systems in the Complete Bipartite Graph Plus a One-Factor. SIAM J. Discrete Math. 21(4): 1083-1092 (2008)

Yeow Meng Chee, San Ling: Improved Lower Bounds for Constant GC-Content DNA Codes. IEEE Transactions on Information Theory 54(1): 391-394 (2008)

Hao Chen, San Ling, Chaoping Xing: Access Structures of Elliptic Secret Sharing Schemes. IEEE Transactions on Information Theory 54(2): 850-852 (2008)

Yeow Meng Chee, Son Hoang Dau, Alan C. H. Ling, San Ling: The Sizes of Optimal q -Ary Codes of Weight Three and Distance Four: A Complete Solution. IEEE Transactions on Information Theory 54(3): 1291-1295 (2008)

Zhifang Zhang, Mulan Liu, Yeow Meng Chee, San Ling, Huaxiong Wang: Strongly Multiplicative and 3-Multiplicative Linear Secret Sharing Schemes. ASIACRYPT 2008: 19-36

Ron Steinfeld, Scott Contini, Krystian Matusiewicz, Josef Pieprzyk, Jian Guo, San Ling, Huaxiong Wang: Cryptanalysis of LASH. FSE 2008: 207-223

Yi Lu, Huaxiong Wang, San Ling: Cryptanalysis of Rabbit. ISC 2008: 204-214

Yeow Meng Chee, San Ling: Improved Lower Bounds for Constant GC-Content DNA Codes. CoRR abs/0803.3657 (2008)

Yeow Meng Chee, Son Hoang Dau, Alan C. H. Ling, San Ling: The Sizes of Optimal q-Ary Codes of Weight Three and Distance Four: A Complete Solution. CoRR abs/0803.3658 (2008)

Zhifang Zhang, Mulan Liu, Yeow Meng Chee, San Ling, Huaxiong Wang: Strongly Multiplicative and 3-Multiplicative Linear Secret Sharing Schemes. CoRR abs/0812.2518 (2008)

San Ling, Ferruh Özbudak: Constructions and bounds on linear error-block codes. Des. Codes Cryptography 45(3): 297-316 (2007)

Yeow Meng Chee, Alan C. H. Ling, San Ling, Hao Shen: The PBD-Closure of Constant-Composition Codes. IEEE Transactions on Information Theory 53(8): 2685-2692 (2007)

Feng Bao, San Ling, Tatsuaki Okamoto, Huaxiong Wang, Chaoping Xing (Eds.): Cryptology and Network Security, 6th International Conference, CANS 2007, Singapore, December 8-10, 2007, Proceedings. Lecture Notes in Computer Science 4856, Springer 2007, isbn 978-3-540-76968-2

Yeow Meng Chee, San Ling: Constructions of q-Ary Constant-Weight Codes. CoRR abs/0705.0081 (2007)

Yeow Meng Chee, Alan C. H. Ling, San Ling, Hao Shen: The PBD-Closure of Constant-Composition Codes. CoRR abs/0712.2552 (2007)

Scott Contini, Krystian Matusiewicz, Josef Pieprzyk, Ron Steinfeld, Jian Guo, San Ling, Huaxiong Wang: Cryptanalysis of LASH. IACR Cryptology ePrint Archive 2007: 430 (2007)

San Ling, Chaoping Xing, Ferruh Özbudak: An explicit class of codes with good parameters and their duals. Discrete Applied Mathematics 154(2): 346-356 (2006)

San Ling, Harald Niederreiter, Patrick Solé: On the Algebraic Structure of Quasi-cyclic Codes IV: Repeated Roots. Des. Codes Cryptography 38(3): 337-361 (2006)

Steven T. Dougherty, San Ling: Cyclic Codes Over Z₄ of Even Length. Des. Codes Cryptography 39(2): 127-153 (2006)

San Ling, Ferruh Özbudak: Aperiodic and Odd Correlations of Some p-Ary Sequences from Galois Rings. IEICE Transactions 89-A(9): 2258-2263 (2006)

Yuansheng Tang, San Ling, Fang-Wei Fu: On the reliability-order-based decoding algorithms for binary linear block codes. IEEE Transactions on Information Theory 52(1): 328-336 (2006)

Keqin Feng, San Ling, Chaoping Xing: Asymptotic bounds on quantum codes from algebraic geometry codes. IEEE Transactions on Information Theory 52(3): 986-991 (2006)

Shu-Tao Xia, Fang-Wei Fu, San Ling: A Lower Bound on the Probability of Undetected Error for Binary Constant Weight Codes. IEEE Transactions on Information Theory 52(9): 4235-4243 (2006)

Fang-Wei Fu, San Ling, Chaoping Xing: On the variance of average distance of subsets in the Hamming space. Discrete Applied Mathematics 145(3): 465-478 (2005)

San Ling, Ferruh Özbudak: Improved p-ary Codes and Sequence Families from Galois Rings of Characteristic p². SIAM J. Discrete Math. 19(4): 1011-1028 (2005)

San Ling, Patrick Solé: On the algebraic structure of quasi-cyclic codes III: generator theory. IEEE Transactions on Information Theory 51(7): 2692-2700 (2005)

Hao Chen, San Ling, Chaoping Xing: Quantum codes from concatenated algebraic-geometric codes. IEEE Transactions on Information Theory 51(8): 2915-2920 (2005)

Shu-Tao Xia, Fang-Wei Fu, Yong Jiang, San Ling: The Probability of Undetected Error for Binary Constant-Weight Codes. IEEE Transactions on Information Theory 51(9): 3364-3373 (2005)

San Ling, Ferruh Özbudak: Improved Bounds on Weil Sums over Galois Rings and Homogeneous Weights. WCC 2005: 412-426

Koichi Betsumiya, San Ling, Fidel R. Nemenzo: Type II codes over F_2^m+uF_2^m. Discrete Mathematics 275(1-3): 43-65 (2004)

San Ling: A family of group character codes. Eur. J. Comb. 25(4): 579-590 (2004)

Jyrki T. Lahtonen, San Ling, Patrick Solé, Dmitrii Zinoviev: Z₈-Kerdock codes and pseudorandom binary sequences. J. Complexity 20(2-3): 318-330 (2004)

Yuansheng Tang, San Ling: On Viterbi-like algorithms and their application to Reed-Muller codes. J. Complexity 20(2-3): 438-457 (2004)

San Ling, Chaoping Xing: Polyadic codes revisited. IEEE Transactions on Information Theory 50(1): 200-207 (2004)

San Ling, Ferruh Özbudak: An improvement on the bounds of Weil exponential sums over Galois rings with some applications. IEEE Transactions on Information Theory 50(10): 2529-2543 (2004)

San Ling, Ferruh Özbudak: Improved p-ary Codes and Sequence Families from Galois Rings. SETA 2004: 236-242

San Ling, Patrick Solé: Nonlinear p-ary Sequences. Appl. Algebra Eng. Commun. Comput. 14(2): 117-125 (2003)

San Ling, Patrick Solé: On the Algebraic Structure of Quasi-cyclic Codes II: Chain Rings. Des. Codes Cryptography 30(1): 113-130 (2003)

San Ling, Patrick Solé: Good self-dual quasi-cyclic codes exist. IEEE Transactions on Information Theory 49(4): 1052-1053 (2003)

Fang-Wei Fu, San Ling, Chaoping Xing: New lower bounds and constructions for binary codes correcting asymmetric errors. IEEE Transactions on Information Theory 49(12): 3294-3299 (2003)

Ka Hin Leung, San Ling, Chaoping Xing: New binary linear codes from algebraic curves. IEEE Transactions on Information Theory 48(1): 285-287 (2002)

San Ling, Jason Thomas Blackford: Z_pk+1-Linear codes. IEEE Transactions on Information Theory 48(9): 2592-2605 (2002)

San Ling, Patrick Solé: Duadic Codes over F₂ + uF₂. Appl. Algebra Eng. Commun. Comput. 12(5): 365-379 (2001)

San Ling, Patrick Solé: Type II Codes OverF₄ + uF₄. Eur. J. Comb. 22(7): 983-997 (2001)

San Ling, Patrick Solé: Decomposing Quasi-Cyclic Codes. Electronic Notes in Discrete Mathematics 6: 412-422 (2001)

San Ling, Patrick Solé: Duadic codes over Z_2k. IEEE Transactions on Information Theory 47(4): 1581-1588 (2001)

Hao Chen, San Ling, Chaoping Xing: Asymptotically good quantum codes exceeding the Ashikhmin-Litsyn-Tsfasman bound. IEEE Transactions on Information Theory 47(5): 2055-2058 (2001)

San Ling, Patrick Solé: On the algebraic structure of quasi-cyclic codes I: Finite fields. IEEE Transactions on Information Theory 47(7): 2751-2760 (2001)

Cunsheng Ding, David R. Kohel, San Ling: Secret-sharing with a class of ternary codes. Theor. Comput. Sci. 246(1-2): 285-298 (2000)

Cunsheng Ding, David R. Kohel, San Ling: Elementary 2-group character codes. IEEE Transactions on Information Theory 46(1): 280-284 (2000)

Cunsheng Ding, David R. Kohel, San Ling: Split group codes. IEEE Transactions on Information Theory 46(2): 485-495 (2000)

Chaoping Xing, San Ling: A class of linear codes with good parameters from algebraic curves. IEEE Transactions on Information Theory 46(4): 1527-1532 (2000)

Chaoping Xing, San Ling: A class of linear codes with good parameters. IEEE Transactions on Information Theory 46(6): 2184-2188 (2000)

Seng Kiat Chua, Ka Hin Leung, San Ling: Attack on RSA-Type Cryptosystems Based on Singular Cubic Curves over Z/nZ. Theor. Comput. Sci. 226(1-2): 19-27 (1999)

Seng Kiat Chua, San Ling: A Rabin-Type Scheme Based on y² equiv x³ + bx² mod n. COCOON 1997: 186-191

Kwok-Yan Lam, San Ling, Lucas Chi Kwong Hui: Efficient Generation of Elliptic Curve Cryptosystems. COCOON 1996: 411-416