Some Remarks on Cocks'Identity-Based Encryption Scheme

The theory of quadratic residues plays an important role in cryptography.In 2001,Cocks developed an identity-based encryption(IBE)scheme based on quadratic residues,resolving Shamir’s 17-year-old open problem.However,a notable drawback of Cocks’scheme is the significant expansion of the ciphertext,and some of its limitations have been addressed in subsequent research.Recently,Cotan and Teşeleanu highlighted that previous studies on Cocks’scheme relied on a trial-and-error method based on Jacobi symbols to generate the necessary parameters for the encryption process.They enhanced the encryption speed of Cocks’scheme by eliminating this trialand-error method.Based on security analysis,this study concludes that the security of Cotan-Teşeleanu’s proposal cannot be directly derived from the security of the original Cocks’scheme.Furthermore,by adopting the Cotan-Teşeleanu method and introducing an additional variable as a public element,this study develops a similar enhancement scheme that not only accelerates the encryption speed but also provides security equivalent to the original Cocks’scheme.

METHOD FOR CONSTRUCTING TAG-KEM SCHEMES WITH SHORT-MESSAGE PUBLIC-KEY ENCRYPTIONS

Tag key encapsulation mechanism （Tag-KEM）/data encapsulation mechanism （DEM） is a hybrid framework proposed in 2005. Tag-t（EM is one of its parts by using public-key encryption （PKE） technique to encapsulate a symmetric key. In hybrid encryptions, the long-raessage PKE is not desired due to its slow operation. A general method is presented for constructing Tag-KEM schemes with short-message PKEs. The chosen ciphertext security is proved in the random oracle model. In the method, the treatment of the tag part brings no additional ciphertext redundancy. Among all the methods for constructing Tag-KEM, the method is the first one without any validity checking on the tag part, thus showing that the Tag-KEM/DEM framework is superior to KEM＋DEM one.

A New Forward-Secure Authenticated Encryption Scheme with Message Linkages

Yoon and Yoo recently proposed a robust authenticated encryption scheme and claimed their scheme has the properties of forward secrecy and confidentiality. The current paper, however, points out that Yoon-Yoo＇s scheme also can not provide forward secrecy and confidentiality such that any adversary can easily recover the transferred message. Based on intractability of reversing the one-way hash function and discrete logarithm problem, an improved authenticated encryption scheme with messages linkage is proposed. The above security faults get solved perfectly. The new scheme is proven to satisfy all the basic security requirements of the authenticated encryption scheme. And by the concrete comparison, it has the similar efficiency of the original scheme.

A NEW PUBLIC-KEY ENCRYPTION SCHEME BASED ON LUCAS SEQUENCE

Investigated the properties of LUCas sequence(LUC), the paper proposed a new variant of (probabilistic) public-key encryption scheme. Security analysis of the proposed encryption schemes shows that its one-wayness is equivalent to partial LUC discrete logarithm problem in ZN, and for the proposed probabilistic encryption scheme, its semantic security is equivalent to decisional LUC Diffie-Hellman problem in ZN. At last, the efficiency of the proposed schemes is briefly analyzed.

Attribute-Based Re-Encryption Scheme in the Standard Model

In this paper, we propose a new attribute-based proxy re-encryption scheme, where a semi-trusted proxy, with some additional information, can transform a ciphertext under a set of attributes into a new ciphertext under another set of attributes on the same message, but not vice versa, furthermore, its security was proved in the standard model based on decisional bilinear Diffie-Hellman assumption. This scheme can be used to realize fine-grained selectively sharing of encrypted data, but the general proxy rencryption scheme severely can not do it, so the proposed schemecan be thought as an improvement of general traditional proxy re-encryption scheme.

New chaos-based encryption scheme for digital sequence

To enhance the anti-breaking performance of privacy information, this article proposes a new encryption method utilizing the leaping peculiarity of the periodic orbits of chaos systems. This method maps the secret sequence to several chaos periodic orbits, and a short sequence obtained by evolving the system parameters of the periodic orbits in another nonlinear system will be the key to reconstruct these periodic orbits. In the decryption end, the shadowing method of chaos trajectory based on the modified Newton-Raphson algorithm is adopted to restore these system parameters. Through deciding which orbit each pair coordinate falls on, the original digital sequence can be decrypted.

Efficient Watermarking Scheme for Traitor Tracing Encryption Schemes

In the content distribution services,traitor tracing encryption schemes are useful tools to trace illegal users that distribute content illegally to unauthorized users.However,solo use of these schemes does not necessarily work well and has vulnerability.To complement the property of the traitor tracing schemes,it is effective to use watermarking scheme with them and the watermarking schemes with light load are required.A number of video watermarking methods with light load have been proposed that embed information into compressed video streams.When the compression scheme is MPEG2-Video,its codes are mostly pre-defined using coding tables,and therefore,information can be embedded in the compressed stream by substituting some of the codes.On the other hand,HEVC/H.265 uses arithmetic coding(CABAC)and it is not easy to substitute one code for another in a stream.To deal with this problem,a watermarking scheme for HEVC/H.265 video streams is proposed.It embeds information while the video is being encoded.A broadcasting system incorporating the scheme is also proposed.

A Method of Homomorphic Encryption

The existing homomorphie eneryption scheme is based on ring of the integer, and the possible operators are restricted to addition and multiplication only. In this paper, a new operation is defined Similar Modul. Base on the Similar Modul, the number sets of the homomorphic encryption scheme is extended to real number, and the possible operators are extended to addition, subtraction, multiplication and division. Our new approach provides a practical ways of implementation because of the extension of the operators and the number sets.

A Novel Pipelining Encryption Hardware System with High Throughput and High Integration for 5G

This paper presents a ZUC-256 stream cipher algorithm hardware system in order to prevent the advanced security threats for 5 G wireless network.The main innovation of the hardware system is that a six-stage pipeline scheme comprised of initialization and work stage is employed to enhance the solving speed of the critical logical paths.Moreover,the pipeline scheme adopts a novel optimized hardware structure to fast complete the Mod(231-1)calculation.The function of the hardware system has been validated experimentally in detail.The hardware system shows great superiorities.Compared with the same type system in recent literatures,the logic delay reduces by 47%with an additional hardware resources of only 4 multiplexers,the throughput rate reaches 5.26 Gbps and yields at least 45%better performance,the throughput rate per unit area increases 14.8%.The hardware system provides a faster and safer encryption module for the 5G wireless network.

Offline/online attribute-based searchable encryption scheme from ideal lattices for IoT

1 Introduction The Internet of Things(IoT)has facilitated the development of numerous fields in our lives.However,some equipment in IoT environment lacks sufficient storage and data processing capabilities[1].A feasible strategy is to leverage the powerful computing capabilities of cloud servers to process the data within the IoT devices.

一种改进类提升方案的双彩色图像加密系统

如今图像信息安全面临着严峻的考验,而图像加密技术是应对这一考验最有效的手段之一。由于提升方案在图像加密中具有更快的加解密速度和良好的安全性,所以越来越多基于提升方案的加密系统被提出。文中提出了一种改进类提升方案的双彩色图像加密系统。首先,将彩色图像分成3个通道:R通道、G通道和B通道。然后,将每个图像分别当成魔方的6个面,使用随机序列控制魔方的旋转,从而达到置乱和加密图像的效果。其次,为了使整个系统具有更高的安全性,将改进类提升方案的更新和预测函数由类感知器网络(Perceptron-Like Network,PLN)代替。与原先运算简单的线性函数相比,PLN具有更加复杂的计算和不可预测性。通过所提结构得到的加密图像具有更高的加密质量,因此可以更好地将图像信息扩散到各个像素之间。大量的实验结果表明,该系统可以很好地抵抗各种攻击,具有很高的安全性;并且本系统对普通图像和密钥都具有很强的敏感性,因此可以应用于实际的图像加密。

An Authenticated Identity-Based Key Establishment and Encryption Scheme for Wireless Sensor Networks

Security of wireless sensor networks has received considerable attention. It is a critical challenge to find out suitable encryption schemes for wireless sensor networks due to limitations of power, computation capability and storage resources of these networks. Many encryption schemes based on asymmetric and symmetric have been investigated. In this paper, we present an authenticated identity-based key encryption scheme for wireless sensor networks. We first review briefly about identity-based encryption and decryption, particularly, the Boneh-Franklin algorithms, then describe an authenticated identity-based key encryption scheme based on Boneh-Franklin algorithms, and finally show the integrity of our scheme and discuss its efficiency and security by comparing it with other asymmetric and symmetric encryption schemes.

Efficient hierarchical identity based encryption scheme in the standard model over lattices

Using lattice basis delegation in a fixed dimension, we propose an efficient lattice-based hierarchical identity based encryption（HIBE） scheme in the standard model whose public key size is only（dm^2＋ mn） log q bits and whose message-ciphertext expansion factor is only log q, where d is the maximum hierarchical depth and（n, m, q）are public parameters. In our construction, a novel public key assignment rule is used to averagely assign one random and public matrix to two identity bits, which implies that d random public matrices are enough to build the proposed HIBE scheme in the standard model, compared with the case in which 2d such public matrices are needed in the scheme proposed at Crypto 2010 whose public key size is（2dm^2＋ mn ＋ m） log q. To reduce the message-ciphertext expansion factor of the proposed scheme to log q, the encryption algorithm of this scheme is built based on Gentry＇s encryption scheme, by which m^2 bits of plaintext are encrypted into m^2 log q bits of ciphertext by a one time encryption operation. Hence, the presented scheme has some advantages with respect to not only the public key size but also the message-ciphertext expansion factor. Based on the hardness of the learning with errors problem, we demonstrate that the scheme is secure under selective identity and chosen plaintext attacks.

联盟链下的高效车联网数据安全共享研究

[目的/意义]旨在解决现有的车联网数据共享方案中计算开销大、共享效率低、安全性不足等问题。[方法/过程]设计了一个车联网高效数据安全共享方案,采用基于线性秘密共享(LSSS)的密文策略属性加密(CP-ABE)算法和基于联盟区块链群组技术,实现了车联网高效数据共享,减少数据冗余,并通过共识机制的优化,进一步提高时间效率,同时确保车辆实体的数据安全性和隐私性。[结果/结论]该方案能够适应车联网快速移动、动态变化的复杂特性,可实现灵活访问控制和高自由度的数据共享,满足车联网场景需求。

医疗云平台中个人健康档案转诊时的安全共享方案

为解决医疗云平台共享个人健康档案(personal health record,PHR)存在的隐私泄露和加解密效率不理想的问题,以医疗云平台中帕金森病患者的转诊场景为例,提出了一种基于线性秘密共享的改进密文属性代理重加密方案(improved linear secret sharing based ciphertext attribute proxy re-encryption scheme,LCPS)。该方案利用线性秘密共享技术来隐藏访问策略中的隐私属性,降低因访问策略暴露引发的隐私泄露风险;该方案还对代理重加密算法进行改进,通过减少复杂的双线性运算,提高了加解密效率。结果表明,LCPS在加解密方面的表现要优于其他方案。在判定性q-BDHE(q-decisional bilinear Diffie-Hellman exponent)困难假设下具有选择明文攻击时的不可区分性(indistinguishability under chosen-plaintext attack,IND-CPA)。该方案具有可移植性,同样适用于医疗云中其他病症转诊时的个人健康档案安全共享。

Cryptanalysis of Hwang et al.＇s Improved Encryption Scheme

Recently, Tseng et al. proposed authenticated encryption scheme with message recovery using self-certified public keys. Hwang et al. proposed an attack to show that the Tseng et al.＇s scheme was not secure. And Hwang et al. proposed an improved scheme and claimed to that the new scheme satisfy the security requirement. However, we will show that the improved signature proposed by Hwang et al. is still insecure.

煤矿人员精确定位系统数据存储方案设计

为了满足基于UWB等新型定位技术的煤矿人员精确定位系统数据存储与访问需要,分析了人员精确定位系统的数据结构、操作频率、数据量及存储占用空间大小等的数据情况,总结了系统数据生成与使用的主要特征,提出了基于Redis、MySQL和文件分别存储热数据、温数据和冷数据的混合数据存储架构,并详细阐述了Redis、MySQL、文件的存储关键设计,以及数据加密和基于Web API数据交互服务的数据查询方法。模拟数据测试结果表明:该存储方案具有较高的数据访问效率,能够满足数据存储与业务功能数据查询需要。

Timing and hamming weight attacks on minimal cost encryption scheme

The timing and Hamming weight attacks on the data encryption standard （DES） cryptosystem for minimal cost encryption scheme is presented in this article. In the attack, timing information on encryption processing is used to select and collect effective plaintexts for attack. Then the collected plaintexts are utilized to infer the expanded key differences of the secret key, from which most bits of the expanded secret key are recovered. The remaining bits of the expanded secret key are deduced by the correlations between Hamming weight values of the input of the S-boxes in the first-round. Finally, from the linear relation of the encryption time and the secret key＇s Hamming weight, the entire 56 bits of the secret key are thoroughly recovered. Using the attack, the minimal cost encryption scheme can be broken with 2^23 known plaintexts and about 2^21 calculations at a success rate a 〉 99%. The attack has lower computing complexity, and the method is more effective than other previous methods.

适用于天地一体化网络的无证书密钥协商协议

为了保证天地一体化网络中用户信息的传输安全,改进传统方案的高时延等问题,本文提出一种轻量级的无证书密钥协商方案。首先,本文分析无证书密钥协商协议系统模型,针对天地一体化网络的特点提出协议需要满足双向认证、抗重放、完整性等安全需求。其次,本文选择一种轻量级的无证书加密方案,在此基础上提出密钥协商协议,满足天地一体化网络的资源和安全要求。最终,本文对提出的密钥协商协议进行BAN(Burrow-Adadi-Needham)逻辑安全性分析,并结合软件对协议性能仿真进行比较,结果表明:该方案在满足网络安全性需求的同时实现高效快速的协商。

密码学课程中可证明安全的案例化教学设计

在商用密码产业的快速发展和日益紧迫的国际环境的社会背景下,社会对密码技术专业人才有巨大需求,因此加速培养高质量的密码技术专业人才显得尤为迫切。可证明安全作为密码学理论体系的一部分,在密码学课程中如何教好可证明安全理论是非常重要的。本文通过案例化教学,着重探讨了可证明安全理论在密码学课程中的一种教学设计,旨在提高学生对可证明安全的深入理解和实际操作能力。通过分析公钥加密体系、数字签名体系以及基于身份的签密方案的安全性,本文展示了如何通过具体案例来教授复杂而且抽象的可证明安全理论,确保学生能够在理论学习与实践应用之间建立有效的联系。此外,本文还讨论了案例化教学的优势与针对当前教学方法的改进建议,以适应快速发展的密码产业和不断扩大的职业需求。