Tuan Nguyen Kim^1,*, Duy Ho Ngoc², Nikolay A. Moldovyan³

CMC-Computers, Materials & Continua, Vol.74, No.1, pp. 1475-1491, 2023, DOI:10.32604/cmc.2023.029253

Abstract The representative collective digital signature, which was suggested by us, is built based on combining the advantages of group digital signature and collective digital signature. This collective digital signature schema helps to create a unique digital signature that deputizes a collective of people representing different groups of signers and may also include personal signers. The advantage of the proposed collective signature is that it can be built based on most of the well-known difficult problems such as the factor analysis, the discrete logarithm and finding modulo roots of large prime numbers and the current digital signature standards of the United… More >

Tuan Nguyen Kim^1,*, Duy Ho Ngoc², Nikolay A. Moldovyan³

CMC-Computers, Materials & Continua, Vol.73, No.1, pp. 783-799, 2022, DOI:10.32604/cmc.2022.024677

Abstract The representative collective digital signature scheme allows the creation of a unique collective signature on document M that represents an entire signing community consisting of many individual signers and many different signing groups, each signing group is represented by a group leader. On document M, a collective signature can be created using the representative digital signature scheme that represents an entire community consisting of individual signers and signing groups, each of which is represented by a group leader. The characteristic of this type of letter is that it consists of three elements (U, E, S), one of which (U) is… More >

Tuan Nguyen Kim^1,*, Duy Ho Ngoc², Nikolay A. Moldovyan³

CMC-Computers, Materials & Continua, Vol.73, No.1, pp. 595-610, 2022, DOI:10.32604/cmc.2022.023168

Abstract There have been many digital signature schemes were developed based on the discrete logarithm problem on a finite field. In this study, we use the elliptic curve discrete logarithm problem to build new collective signature schemes. The cryptosystem on elliptic curve allows to generate digital signatures with the same level of security as other cryptosystems but with smaller keys. To extend practical applicability and enhance the security level of the group signature protocols, we propose two new types of collective digital signature schemes based on the discrete logarithm problem on the elliptic curve: i) the collective digital signature scheme shared… More >

Yongli Tang¹, Yuanhong Li¹, Qing Ye^1,*, Ying Li¹, Xiaojun Wang²

CMC-Computers, Materials & Continua, Vol.72, No.2, pp. 4069-4085, 2022, DOI:10.32604/cmc.2022.026820

Abstract Although the existing group signature schemes from lattice have been optimized for efficiency, the signing abilities of each member in the group are relatively single. It may not be suitable for complex applications. Inspired by the pioneering work of Bellare and Fuchsbauer, we present a primitive called policy-based group signature. In policy-based group signatures, group members can on behalf of the group to sign documents that meet their own policies, and the generated signatures will not leak the identity and policies of the signer. Moreover, the group administrator is allowed to reveal the identity of signer when a controversy occurs.… More >

Chaoyang Li^1,*, Yalan Wang², Gang Xu³, Xiubo Chen⁴, Xiangjun Xin¹, Jian Li⁴

Journal of Cyber Security, Vol.3, No.4, pp. 207-216, 2021, DOI:10.32604/jcs.2021.026926

Abstract Along with the increase of wearable medical device, the privacy leakage problem in the process of transmission between these edge medical devices. The blockchain-enabled Internet of Medical Things (BIoMT) has been developed to reform traditional centralized medical system in recent years. This paper first introduces a data anonymous authentication model to protect user privacy and medical data in BIoMT. Then, a proxy group signature (PGS) scheme has been proposed based on lattice assumption. This scheme can well satisfy the anonymous authentication demand for the proposed model, and provide anti-quantum attack security for BIoMT in the future general quantum computer age.… More >

Yousheng Zhou^1,2, Lvjun Chen¹, Xiaofeng Zhao^1,*, Zheng Yang³

CMES-Computer Modeling in Engineering & Sciences, Vol.125, No.3, pp. 1101-1118, 2020, DOI:10.32604/cmes.2021.013289

Abstract Vehicle sensor networks (VSN) play an increasingly important part in smart city, due to the interconnectivity of the infrastructure. However similar to other wireless communications, vehicle sensor networks are susceptible to a broad range of attacks. In addition to ensuring security for both data-at-rest and data-in-transit, it is essential to preserve the privacy of data and users in vehicle sensor networks. Many existing authentication schemes for vehicle sensor networks are generally not designed to also preserve the privacy between the user and service provider (e.g., mining user data to provide personalized services without infringing on user privacy). Controllable linkability can… More >