A survey on JPEG2000 encryption

Image and video encryption has become a widely discussed topic; especially for the fully featured JPEG2000 compression standard numerous approaches have been proposed. A comprehensive survey of state-of-the-art JPEG2000 encryption is given. JPEG2000 encryption schemes are assessed in terms of security, runtime and compression performance and their suitability for a wide range of application scenarios.     

A survey of certificateless encryption schemes and security models

This paper surveys the literature on certificateless encryption schemes. In particular, we examine the large number of security models that have been proposed to prove the security of certificateless encryption schemes and propose a new nomenclature for these models. This allows us to “rank” the notions of security for a certificateless encryption scheme against an outside attacker and a passive key generation centre, and we suggest which of these notions should be regarded as the “correct” model for a secure certificateless encryption scheme. We also examine the security models that aim to provide security against an actively malicious key generation centre and against an outside attacker who attempts to deceive a legitimate sender into using an incorrect public key (with the intention to deny the legitimate receiver that ability to decrypt the ciphertext). We note that the existing malicious key generation centre model fails to capture realistic attacks that a malicious key generation centre might make and propose a new model. Lastly, we survey the existing certificateless encryption schemes and compare their security proofs. We show that few schemes provide the “correct” notion of security without appealing to the random oracle model. The few schemes that do provide sufficient security guarantees are comparatively inefficient. Hence, we conclude that more research is needed before certificateless encryption schemes can be thought to be a practical technology.     

H.264标准中基于感知加密算法的视频加密方案

针对多媒体视频传输的安全性与实时性的要求,提出一种基于H.264感知加密算法的视频加密方案.该方案将视频数据分为VLC(Variable Length Code)和FLC(Fix-Length Code)两类,只选择FLC中对重构图像比较重要的元素进行加密操作.理论分析和仿真结果表明,该加密方案具有安全性高,低成本系统开销的特性.     

Searchable encryption on the cloud: a survey

The Journal of Supercomputing - Outsourcing data to the cloud can be considered as a perfect solution for the storage and computationally constrained data owners. However, data confidentiality is...     

A knapsack-based probabilistic encryption scheme

Knapsack-based cryptosystems had been viewed as the most attractive and the most promising asymmetric cryptographic algorithms for a long time due to their NP-completeness nature and high speed in encryption/decryption. Unfortunately, most of them are broken for the low-density feature of the underlying knapsack problems. In this paper, we investigate a new easy compact knapsack problem and propose a novel knapsack-based probabilistic public-key cryptosystem in which the cipher-text is non-linear with the plaintext. For properly chosen parameters, the underlying knapsack problem enjoys a high density larger than 1.06 in the worst case. Hence, it is secure against the low-density subset-sum attacks. Our scheme can also defeat other potential attacks such as the brute force attacks and the simultaneous Diophantine approximation attack. Compared with previous knapsack-based cryptosystems, our scheme is efficient and practical.     

一种混沌图像加密算法研究

针对传统基于混沌加密系统没有考虑图像信息自身特点的缺点,文章提出了一种混沌图像加密算法。该算法首先利用混沌理论的到图像的混沌序列,然后通过DCT变换对得到的序列进行位置置乱、灰度值替代的加密处理。文章还对此算法密钥空间、密钥敏感性、抗噪声性能和抗破损性能分别进行了分析。仿真结果和性能分析表明,在保证加密性能的同时,不但图像的存储容量大大减小,而且图像的传输速度也得到了有效地提升。     

一种文件智能加密方法研究

经典的文件加密算法（如AES等）有一个特点,即加密后的文件是乱码。这极容易被攻击者识别,进而实施暴力破解或干脆破坏文件。本文就这一问题,尝试根据文件的不同格式对文件进行智能加解密,在保证对文件重要数据进行加密的基础上,不破坏文件甚至是文件数据的原有格式,目标是使攻击者难以识别该文件是加密后文件,以达到更好的数据保护的目的。     

A taxonomy of standards

Objectivity, Inc., markets an engineering database management system that is an OODBMS. We are committed to the idea that standards are beneficial for all players in the industry. We have played active roles in several standardization efforts, including the CAD Framework Initiative (CFI). This proposal discusses the motivation for a standardization effort, suggests a direction for its development, discusses cooperation with other such efforts, and offers some concrete starting suggestions.     

Evidence management for compliance of critical systems with safety standards: A survey on the state of practice

ContextDemonstrating compliance of critical systems with safety standards involves providing convincing evidence that the requirements of a standard are adequately met. For large systems, practitioners need to be able to effectively collect, structure, and assess substantial quantities of evidence.ObjectiveThis paper aims to provide insights into how practitioners deal with safety evidence management for critical computer-based systems. The information currently available about how this activity is performed in the industry is very limited.MethodWe conducted a survey to determine practitioners’ perspectives and practices on safety evidence management. A total of 52 practitioners from 15 countries and 11 application domains responded to the survey. The respondents indicated the types of information used as safety evidence, how evidence is structured and assessed, how evidence evolution is addressed, and what challenges are faced in relation to provision of safety evidence.ResultsOur results indicate that (1) V&V artefacts, requirements specifications, and design specifications are the most frequently used safety evidence types, (2) evidence completeness checking and impact analysis are mostly performed manually at the moment, (3) text-based techniques are used more frequently than graphical notations for evidence structuring, (4) checklists and expert judgement are frequently used for evidence assessment, and (5) significant research effort has been spent on techniques that have seen little adoption in the industry. The main contributions of the survey are to provide an overall and up-to-date understanding of how the industry addresses safety evidence management, and to identify gaps in the state of the art.ConclusionWe conclude that (1) V&V plays a major role in safety assurance, (2) the industry will clearly benefit from more tool support for collecting and manipulating safety evidence, and (3) future research on safety evidence management needs to place more emphasis on industrial applications.     

一种医学影像数据选择性的加密方法

随着云计算与大数据技术的发展,为解决昂贵医学影像设备所产生的在国内区域影像数据安全共享服务要求,结合多媒体特别是医学影像数据量大等特点,基于S CAN语言提出一种选择性加密算法,结合数据本身的哈希值作为位加密周期序列,实现个人医学影像数据的隐私安全保护。通过安全性分析与仿真实验证明该算法具有较好的置乱等效果。     

A software scheme for user-controlled file encryption

An implementation of a technique, based on the Data Encryption Standard (DES), is described for user-controlled encryption of files. The user supplies a privately selected character string as a key and also the desired number of DES iterations. The actual encryption key and initial chaining value for block-chaining are derived from this private key for encryption of the user file. The implementation is adaptible for use on both time-sharing systems and personal computer systems.     

一种混合型混沌图像加密算法的设计

本文设计了一种结合Cat和Logistic映射的混合型混沌加密算法。首先文章给出了该图像加解密的算法流程,在置乱变换和扩散变换主要算法程序的基础上,对实验结果从密钥空间、图像的直方图、图像的相关性、图像的信息熵等方面进行了分析,证明该算法对图像信息加解密具有良好的效果。     

A new encryption scheme for surveillance videos

In this paper, we propose a novel framework to encrypt surveillance videos. Although a few encryption schemes have been proposed in the literature, they are not sufficiently efficient due to the lack of full consideration of the characteristics of surveillance videos, i.e., intensive global redundancy. By taking advantage of such redundancy, we design a novel method for encrypting such videos. We first train a background dictionary based on several frame observations. Then every single frame is parsed into the background and foreground components. Separation is the key to improve the efficiency of the proposed technique, since encryption is only carried out in the foreground,while the background is skillfully recorded by corresponding background recovery coefficients. Experimental results demonstrate that, compared to the state of the art, the proposed method is robust to known cryptanalytic attacks, and enhances the overall security due to the foreground and background separation. Additionally, our encryption method is faster than competing methods, which do not conduct foreground extraction.     

A fast ARX model-based image encryption scheme

This paper proposes a novel ARX model-based image encryption scheme that uses addition, rotation, and XOR as its confusion and diffusion mechanism instead of S-Box and permutation as in SP networks. The confusion property of the proposed scheme is satisfied by rotation and XOR with chaotic sequences generated from two logistic maps. Unlike classical image encryption schemes that adopt S-Box or permutation of the entire plain image, the diffusion property is satisfied using addition operations. The proposed scheme exhibits good performance on correlation coefficients (horizontal, vertical and diagonal), Shannon’s entropy and NPCR (Number of Pixels Change Rate). Furthermore, simulation results indicate that its time complexity is 9.2 times more efficient than the fastest algorithm(Yang’s algorithm).     

A property-based testing framework for encryption programs

In recent years, a variety of encryption algorithms were proposed to enhance the security of software and systems. Validating whether encryption algorithms are correctly implemented is a challenging issue. Software testing delivers an effective and practical solution, but it also faces the oracle problem (that is, under many practical situations, it is impossible or too computationally expensive to know whether the output for any given input is correct). In this paper, we propose a property-based approach to testing encryption programs in the absence of oracles. Our approach makes use of the so-called metamorphic properties of encryption algorithms to generate test cases and verify test results. Two case studies were conducted to illustrate the proposed approach and validate its effectiveness. Experimental results show that even without oracles, the proposed approach can detect nearly 50% inserted faults with at most three metamorphic relations (MRs) and fifty test cases.     

A novel multi-dimensional multiple image encryption technique

Multimedia Tools and Applications - This paper proposes a novel secure and fast multiple image encryption technique to encrypt multiple images of arbitrary sizes. In the proposed technique, a group...     

Network encryption

For organizations or individuals who wish to protect the confidentiality of their data when it is in transit across communications networks, network level encryption offers an efficient and proven method for preserving data privacy. Use of encryption on a network also offers anti-hacking protection since a hacker's communications are likely to originate from outside the encrypted network and hence will be discarded. This article provides an overview of the different approaches to network encryption together with the related key management aspects.     

Gauss-Markov加密矩阵构造及图像加密应用

为了解决加密矩阵难以构造的问题,提出一种获得整数矩阵的新算法,利用Gauss-Markov过程生成一个随机序列,将该序列转换为一系列的低阶整数矩阵,从中寻找行列式等于l的整数矩阵,并对这些矩阵进行张量积运算得到高阶加密矩阵,应用于数字图像加密.加密实例和理论分析及对比表明,该算法可自动生成安全性很高的加密矩阵,且加密结果具有良好的随机特性和自相关性,能满足密码学的要求.     

一种新的基于RSA广播加密方案

在对基于身份广播加密IBBE研究的基础上,提出了基于RSA加密技术的新广播加密方案,并给出了新方案的形式化定义和安全模型。在标准模型下,证明了新方案具有针对静态对手的选择明文攻击安全性。新方案中用户的私钥长度仅为,并且在满足抗完全同谋攻击前提下,新方案降低了解密开销。实验结果表明,新方案在解密计算量和存储量上更具有优势,更适用于广播集合固定的应用。