Modifications of arithmeticcoding (AC) have been proposed to improve the security of traditional AC. Two main modifications to AC are randomized AC (RAC) and AC with key-based interval splitting (KSAC). Chosen-plaint...
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Modifications of arithmeticcoding (AC) have been proposed to improve the security of traditional AC. Two main modifications to AC are randomized AC (RAC) and AC with key-based interval splitting (KSAC). Chosen-plaintext attacks have been proposed for these two methods when the same key is used to encrypt different messages. We first give a definition for security of encryption using AC that is based on the inability of the adversary to distinguish between the encryption of one plaintext from the encryption of another. Using this definition, we prove that RAC is insecure even if a new random key is used to compress every message. Our proof assumes that the adversary can only eavesdrop on the ciphertext and cannot request encryptions of chosen-plaintexts. We then prove that the method of first-compress-then-encrypt, where the encryption is performed by a bitwise XOR of the compressed output with a pseudorandom bit sequence, is provably secure with respect to chosen-plaintext attacks. If the pseudorandom bit sequence is derived in advance using Advanced Encryption Standard (AES) in the counter mode, then the first-compress-then-encrypt method results in a performance penalty of only a few two input XOR-gate delays.
In this paper, we propose a novel secure arithmeticcoding based on digitalized modified logistic map (DMLM) and linear feedback shift register (LFSR). An input binary sequence is first mapped into a table, which is t...
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In this paper, we propose a novel secure arithmeticcoding based on digitalized modified logistic map (DMLM) and linear feedback shift register (LFSR). An input binary sequence is first mapped into a table, which is then scrambled by two cyclic shift steps driven by the keys resulting from DMLM-LFSR. Next, each column is encoded using traditional arithmeticcoding (TAC) and randomized arithmetic coding (RAC). During the RAC process, the exchange of two intervals is controlled by the keystream generated from the DMLM. At the same time, a few bits of the present column sequence are extracted to interfere the generation of new keystream used for the next column. The final ciphertext sequence is obtained by XORing the compressed sequence and the keystream generated by the LFSR. Results show the compression ratio of our scheme is slightly higher than that of TAC, but the security is improved due to the architecture of shift-perturbance. DMLM and LFSR theories also ensure high sensitivity and strong randomness. The appended complexity is only O(N), where N is the number of the input symbols. (C) 2015 Elsevier B.V. All rights reserved.
Encryption is one of the fundamental technologies that is used in digital rights management. Unlike ordinary computer applications, multimedia applications generate large amounts of data that has to be processed in re...
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Encryption is one of the fundamental technologies that is used in digital rights management. Unlike ordinary computer applications, multimedia applications generate large amounts of data that has to be processed in real time. So, a number of encryption schemes for multimedia applications have been proposed in recent years. We analyze the following proposed methods for multimedia encryption: key-based multiple Huffman tables (MHT), arithmeticcoding with key-based interval splitting (KSAC), and randomized arithmetic coding (RAC). Our analysis shows that MHT and KSAC are vulnerable to low complexity known- and/or chosen-plaintext attacks. Although we do not provide any attacks on RAC, we point out some disadvantages of RAC over the classical compress-then-encrypt approach.
This paper presents a secure integer arithmetic code that owns the capabilities of compression and encryption simultaneously. It is quite different from the randomizedarithmetic code, the interval splitting arithmeti...
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ISBN:
(纸本)9781467360500
This paper presents a secure integer arithmetic code that owns the capabilities of compression and encryption simultaneously. It is quite different from the randomizedarithmetic code, the interval splitting arithmetic code, and the secure arithmetic code. All of them are applied to float-point arithmeticcoding. Instead of float-point implementation, integer implementation is more popular since it can decrease the computational cost of arithmeticcoding without inducing significant compression loss. During the implementation of integer arithmeticcoding, we find that it is possible to lower the instantaneous entropy through the adjustment of interval size. Hence, we can design a secure integer arithmetic code (SIAC) with high security, and the compression efficiency of this code is almost the same or even higher than that of the traditional integer arithmetic code (TIAC).
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