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Improving performance of network covert timing channel through huffman coding

MATHEMATICAL AND COMPUTER MODELLING 2012年第1-2期55卷 69-79页

作者： Wu, Jingzheng Wang, Yongji Ding, Liping Liao, Xiaofeng Chinese Acad Sci Inst Software Natl Engn Res Ctr Fundamental Software Beijing 100190 Peoples R China Chinese Acad Sci Grad Sch Beijing 100190 Peoples R China Chinese Acad Sci Inst Software State Key Lab Comp Sci Beijing 100190 Peoples R China

Network covert channel is a mechanism used to transfer covert message violating security policies through network. Performance of a channel is crucial to an attacker. Some studies have improved the performance by advancing the coding mechanism, but few ones have taken account of the redundancy of covert message. This paper introduces huffman coding scheme to compress the transferred data by exploiting redundancy, and investigates the performance of the network timing channel according to the channel capacity and covertness. A mathematical model of capacity is presented and the effects of the parameters are analyzed. The experiment examines how the network delays and the huffman coding scheme affect the capacity and covertness, and the results demonstrate that the performance of the timing channel is improved. (C) 2011 Elsevier Ltd. All rights reserved.

关键词： huffman coding Network covert channel Covert channel encoding Capacity Covertness Timing channel

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huffman coding Inspired Peer-to-Peer Multicasting

Huffman Coding Inspired Peer-to-Peer Multicasting

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10th International Symposium on Electronics and Telecommunications (ISETC)

作者： Polaczyk, Bartosz Cholda, Piotr Jajszczyk, Andrzej AGH Univ Sci & Technol Dept Telecommun Krakow Poland

An adaptive algorithm, inspired by the huffman code generation, for constructing a network-aware Peer-to-Peer (P2P) video multicast is proposed. The centralized and distributed variants of the algorithm are presented.... 详细信息

ISBN: (纸本)9781467311762

关键词： huffman coding live streaming multicast routing Peer-to-Peer (P2P) Quality of Service (QoS)

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A quantum analog of huffman coding

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IEEE TRANSACTIONS ON INFORMATION THEORY 2000年第4期46卷 1644-1649页

作者： Braunstein, SL Fuchs, CA Gottesman, D Lo, HK Univ Wales SEECS Bangor LL57 1UT Gwynedd Wales Hewlett Packard Labs Bristol BS34 8QZ Avon England CALTECH Norman Bridge Lab Phys 12 33 Pasadena CA 91125 USA Univ Calif Los Alamos Natl Lab Los Alamos NM 87545 USA MagiQ Technol Inc New York NY 10001 USA

We analyze a generalization of huffman coding to the quantum ease. In particular, Re notice various difficulties in using instantaneous codes for quantum communication. Nevertheless, for the storage of quantum information, we have succeeded in constructing a huffman-coding-inspired quantum scheme. The number of computational steps in the encoding and decoding processes of N quantum signals can be made to be of polylogarithmic depth by a massively parallel implementation of a quantum gate array. This is to be compared with the O(N-8) computational steps required in the sequential implementation by Cleve and DiVincenzo of the well-known quantum noiseless block-coding scheme of Schumacher. We also show that O(N-2(log N)(a)) sequential computational steps are needed for the communication of quantum information using another huffman-coding-inspired scheme where the sender must disentangle her encoding device before the receiver can perform any measurements on his signals.

关键词： data compression huffman coding instantaneous codes quantum coding quantum information variable-length codes

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A novel DNA sequence similarity calculation based on simplified pulse-coupled neural network and huffman coding

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PHYSICA A-STATISTICAL MECHANICS AND ITS APPLICATIONS 2016年第0期461卷 325-338页

作者： Jin, Xin Nie, Rencan Zhou, Dongming Yao, Shaowen Chen, Yanyan Yu, Jiefu Wang, Quan Yunnan Univ Sch Informat Kunming 650091 Peoples R China Yunnan Univ Sch Software Kunming 650091 Peoples R China Yunnan Univ Sch Life Sci Kunming 650091 Peoples R China

A novel method for the calculation of DNA sequence similarity is proposed based on simplified pulse-coupled neural network (S-PCNN) and huffman coding. In this study, we propose a coding method based on huffman coding, where the triplet code was used as a code bit to transform DNA sequence into numerical sequence. The proposed method uses the firing characters of S-PCNN neurons in DNA sequence to extract features. Besides, the proposed method can deal with different lengths of DNA sequences. First, according to the characteristics of S-PCNN and the DNA primary sequence, the latter is encoded using huffman coding method, and then using the former, the oscillation time sequence (OTS) of the encoded DNA sequence is extracted. Simultaneously, relevant features are obtained, and finally the similarities or dissimilarities of the DNA sequences are determined by Euclidean distance. In order to verify the accuracy of this method, different data sets were used for testing. The experimental results show that the proposed method is effective. (C) 2016 Published by Elsevier B.V.

关键词： Simplified pulse-coupled neural network DNA sequence Sequence similarity huffman coding Euclidean distance

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An efficient bitwise huffman coding technique based on source mapping

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COMPUTERS & ELECTRICAL ENGINEERING 2001年第3期27卷 265-272页

作者： Elabdalla, AR Irshid, MI Jordan Univ Sci & Technol Dept Elect Engn Irbid 22110 Jordan

In this paper, we propose an efficient source encoding technique based on mapping a non-binary information source with a large alphabet onto an equivalent binary source using weighted fixed-length code assignments. The weighted codes are chosen such that the entropy of the resulting binary source multiplied by the code length is made as close as possible to that of the original non-binary source. It is found that a large saving in complexity, execution time, and memory size is achieved when the commonly used source encoding algorithms are applied to the nth-order extension of the resulting binary source. This saving is due to the large reduction in the number of symbols in the alphabet of the new extended binary source. As an example to validate the effectiveness of this approach, text compression using huffmann encoder applied to the nth-order extended binary source is studied. It is found that the bitwise huffman encoder of the fourth-order extended binary source (16 symbols) achieves a compression efficiency close to that of the conventional huffman encoder (256 symbols). (C) 2001 Elsevier Science Ltd. All rights reserved.

关键词： data compression source mapping huffman coding

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A Novel Hybrid Medical Data Compression Using huffman coding and LZW in IoT

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IETE JOURNAL OF RESEARCH 2023年第11期69卷 7831-7845页

作者： Mohammadi, Hossein Ghaderzadeh, Abdulbaghi Ahmadi, Amir Sheikh Islamic Azad Univ Dept Comp Engn Sanandaj Branch Sanandaj Iran

Today, telemedicine has become very essential, because it provides the possibility for the health centers, hospitals, and research centers to exchange medical and diagnostic data, under IoT. Since the volume of the generated medical information in IoT is very high, transmitting this data via channels of limited bandwidth is time-consuming;thus, the information should be compressed before transmission. Todays, some of the methods compress data significantly, but quality of the restored data in these methods is very low. Considering the importance of images and information for diagnostic and medical applications, desired quality is of great importance. Thus, this study tries to present a hybrid medical information compression technique such that quality of the restored information is desired and compression is efficient. This compression technique combines two lossless compression methods, including huffman encoding and Lempel-Ziv-Welch (LZW) that rearranges information. In this combination, a binary information arrangement is used between Hoffman and LZW techniques so that the integration of binary information reaches an information mapping and, while simplifying the mapping, is completely different for each piece of information and makes this article stand out. The simulation results of the proposed method show that medical information including signal, text, and image is reduced by an average of 37.85%. Remarkably, quality of the restored image is not degraded.

关键词： huffman coding hybrid medical data compression information rearrangement IoT LZW compression telemedicine

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Reversible Data Hiding in Encrypted Images Based on Time-Varying huffman coding Table

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IEEE TRANSACTIONS ON MULTIMEDIA 2023年 25卷 8607-8619页

作者： Yang, Yaolin He, Hongjie Chen, Fan Yuan, Yuan Mao, Ningxiong Southwest Jiaotong Univ Sch Informat Sci & Technol Chengdu 611756 Peoples R China Southwest Jiaotong Univ Sch Comp & Artificial Intelligence Chengdu 611756 Peoples R China

Image privacy protection and management face many challenges, such as privacy disclosure, copyright dispute, and traceability difficulties, with the development of big data. Reversible data hiding in encrypted images (RDHEI) has been widely considered as an effective means to tackle these challenges. In this paper, a RDHEI based on time-varying huffman coding table (TV-HCT) method is proposed to improve the security, embedding rate (ER) and efficiency. First, the initial HCT is generated according to the prediction errors of an image, which can improve compression performance. And then, the TV-HCT is obtained by scrambling equal-length codewords in the initial HCT using timestamps. This realizes the time variability of compression coding stream (CCS) of an image in that the image TV-HCT has large change space. Analysis shows that the average change space of TV-HCT in UCID is 3.97x10(327), and the average ER of three databases is more than 0.44 bpp higher than the existing algorithms. Finally, the CCS is encrypted using the designed index class scrambling method to balance complexity and security. The proposed method not only strengthens the security against brute force attack and differential attack, but also improves ER and efficiency of the RDHEI technique. Experimental results and performance analysis demonstrate that the proposed algorithm outperforms the state-of-the-art RDHEI algorithms in terms of the security, ER and complexity.

关键词： Image coding huffman coding Encryption Complexity theory Indexes Redundancy Resists Encrypted images huffman coding index class scrambling reversible data hiding time-varying

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Generalized huffman coding for binary trees with choosable edge lengths

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INFORMATION PROCESSING LETTERS 2015年第4期115卷 502-506页

作者： Massberg, Jens Univ Ulm Inst Optimizat & Operat Res D-89069 Ulm Germany

In this paper we study binary trees with choosable edge lengths, in particular rooted binary trees with the property that the two edges leading from every non-leaf to its two children are assigned integral lengths l(1) and l(2) with l(1) +l(2) = k for a constant k is an element of N. The depth of a leaf is the total length of the edges of the unique root-leaf-path. We present a generalization of huffman coding that can decide in polynomial time if for given values d(1), ....., d(n) is an element of N >= 0 there exists a rooted binary tree with choosable edge lengths with n leaves having depths at most d(1), ...., d(n). (C) 2014 Elsevier B.V. All rights reserved.

关键词： Combinatorial problems Binary tree Kraft's inequality huffman coding Choosable edge lengths

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MARKOV-huffman coding OF LPC PARAMETERS

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IEEE TRANSACTIONS ON ACOUSTICS SPEECH AND SIGNAL PROCESSING 1985年第2期33卷 451-453页

作者： PAPAMICHALIS, PE Central Research Laboratories Texas Instruments Inc. Dallas TX USA

The methods of Markov modeling and huffman coding are combined to reduce the data rate of LPC-coded speech without any effect on the speech quality. A Markov model is applied to the quantization levels of the LPC parameters, and the transition probabilities are then used to generate huffman coding tables. This procedure does not have any impact on speech quality since it affects only the representation of the quantized parameters. It is demonstrated that Markov-huffman coding can lead to average savings of more than 20 percent in bit rate. A suboptimal scheme is also investigated, which can facilitate the implementation of the method on currently available signal processing chips.

关键词： Linear predictive coding huffman coding Speech coding Bit rate Probability Quantization Signal processing Vocoders Frequency Databases

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An efficient repetition finder for improving dynamic huffman coding

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IEEE TRANSACTIONS ON COMMUNICATIONS 1997年第11期45卷 1363-1366页

作者： Kuo, CH Tsay, MK Lu, CC NATL CENT UNIV INST ELECT ENGNCHUNGLI 320TAIWAN KENT STATE UNIV DEPT MATH & COMP SCIKENTOH 44242

In this paper, a new repetition finder to be used with dynamic huffman coding is proposed to improve the compression efficiency by reducing the redundancy due to string repetitions, Compared to the repetition finder proposed in [4], the proposed scheme effectively increases the numbers of consecutive symbols in the repetition mode and the total number of symbols in the repetition mode, Experimental results show that the proposed method outperforms the repetition finder in [4] by 14-40% in compression ratios with about the same memory requirement and running time.

关键词： data compression huffman coding

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