Many attempts have been made to strengthen Feistel based block ciphers. Among the successful proposals is the key- dependent S-box which was implemented in some of the high-profile ciphers. In this paper a key-dependent permutation box is proposed and implemented on DES as a case study. The new modified DES, MDES, was tested against Diehard Tests, avalanche test, and performance test. The results showed that in general MDES is more resistible to attacks than DES with negligible overhead. Therefore, it is believed that the proposed key-dependent permutation should be considered as a valuable primitive that can help strengthen the security of Substitution-Permutation Network which is a core design in many Feistel based block ciphers.<\/p>\r\n","references":"[1] W. Stallings, Cryptography and Network Security Principles and \r\nPractices. Prentice Hall, 2006. \r\n[2] A. Menezes, P. Van Oorschot, and S. Vanstone, The Handbook of\r\nApplied Cryptography. CRC Press, Inc., 1996. \r\n[3] B. Schneier, Applied Cryptography, Second Edition: Protocols, \r\nAlgorthms, and Source Code in C. John Wiley & Sons, Inc., 1996. \r\n[4] R. Zhang and L. Chen, \"A Block Cipher Using Key-Dependent S-box \r\nand P-boxes,\" in IEEE International Symposium on Industrial \r\nElectronics, ISIE 2008, pp. 1463 - 1468. \r\n[5] The Florida State University, The Marsaglia Random Number CDROM \r\nincluding the Diehard Battery of Tests of Randomness. (Online). \r\nhttp:\/\/www.stat.fsu.edu\/pub\/diehard\/ \r\n[6] V. Katos, \"A Randomness Test for Block Ciphers,\" Applied \r\nMathematics and Computation, Vol. 162, p. 29\u201335, 2005.\r\n[7] M. E. Yalcin, J. A. K. Suykens, and J. Vandewalle, \"A Double Scroll \r\nBased True Random Bit Generator,\" in Proc. IEEE Int. Symp. Circuits \r\nand Systems (ISCAS\u201904), Vancouver, BC, Canada, 2004, p. 581\u2013584. \r\n[8] I. Jang and H. S. Yoo, \"Pseudorandom Number Generator Using Optimal \r\nNormal Basis,\" in Proc. International Conference on Computational \r\nScience and its Applications, Glasgow, Royaume-uni, \r\n2006, vol. 3984, pp. 206-212. \r\n[9] D. Bucerzan, \"A Cryptographic Algorithm Based on a Pseudorandom \r\nNumber Generator,\" in 10th International Symposium on Symbolic and \r\nNumeric Algorithms for Scientific Computing, 2008, pp. 453-456. \r\n[10] P. Hellekalek, and S. Wegekittl, \"Empirical Evidence Concerning AES,\" \r\nACM Transactions on Modeling and Computer Simulation, vol. 13, p. \r\n322\u2013333, 2003. \r\n[11] J. Soto, \"Statistical Testing of Random Number Generators,\" in \r\nProceedings of the 22nd National Information Systems Security \r\nConference, Virginia - USA, 2000. \r\n[12] X. Zhangy, K. Tangy and L. Shuz, \"A Chaotic Cipher Mmohocc and Its \r\nRandomness Evaluation,\" in International Conference on Complex \r\nSystems (ICCS2006), Boston, 2006 [not published]. \r\n[13] K. M. A. Suwais, \"Parallel Platform For New Secure Stream Ciphers \r\nBased On NP-HARD Problems\u201d, Phd thesis, Uinversity Sains Malaysia, \r\n2009. \r\n[14] S. H. Lee, H. Y. Jeong and Y. S. Lee, \"Application-Adaptive Pseudo \r\nRandom Number Generators and Binding Selector,\" in The 23rd \r\nInternational Technical Conference on Circuits\/Systems, Computers and \r\nCommunications, Shimonoseki - Japan, 2008, pp. 1561 - 1564. \r\n[15] F. Pareschi, R. Rovatti and G. Setti, \"Second-level NIST Randomness \r\nTests for Improving Test Reliability,\" in IEEE International Symposium \r\non Circuits and Systems, NewOrleans, 2007, pp. 1437-1440. \r\n[16] \"FIPS 140-1 Non-Proprietary Cryptographic Module Security Policy,\" \r\n2000. http:\/\/csrc.nist.gov\/groups\/STM\/cmvp\/documents\/140-\r\n1\/140sp\/140sp111.pdf. visited in October, 2009. \r\n[17] I. Vattulainen, T. Ala-Nissila and K. Kankaala, \"Physical Tests for \r\nRandom Numbers in Simulations,\" Phys. Rev. Lett. 73, 19, 2513\u20132516.\r\n 1994. \r\n[18] K. H. Tsoi, K. H. Leung and P. H. W. Leong, \"High Performance \r\nPhysical Random Number Generator,\" IET computers & digital \r\ntechniques, pp. 349-352, 2007. \r\n[19] K. H. Yalcin, J. A. K. Suykens and J. Vandewalle, \"True Random Bit \r\nGeneration From a Double-Scroll Attractor,\" in IEEE Transactions on \r\nCircuits and Systems I, 2004, pp. 1395 - 1404. \r\n[20] F. A. Feldman, \"A New Spectral Test for Nonrandomness and the DES,\" \r\nin IEEE Transactions on Software Engineering, 1990, pp. 261 - 267. \r\n[21] A. G. Konheim, Crytography: A Primer. Wiley Interscience, 1981. ","publisher":"World Academy of Science, Engineering and Technology","index":"Open Science Index 38, 2010"}