Quasi-Linear Size Zero Knowledge from Linear-Algebraic PCPs

Reducing operating costs during soil processing and increasing the wear resistance of parts and components is an important condition for reducing the cost of agricultural products, increasing its efficiency and competitiveness. The development of materials with increased wear resistance and new effective technologies for strengthening working bodies in their manufacture is now becoming an urgent task. (Research purpose) The research purpose is increasing the wear resistance of the working bodies of soil-processing machines by electric arc surfacing. (Materials and methods) During the experimental study, it has been performed testing of modes and surfacing of a pilot batch of working bodies from Kverneland for field tests in VIM on an automated installation for electric arc surfacing. Authors used eutectic CastolinEnDotec DO*30 powder wire with a diameter of 1.2 millimeters and a boron content of up to 4 percent for surfacing wear-resistant rollers, which allows to obtain wear-resistant rollers with a hardness of up to 65 HRC without pores and cracks. (Results and discussion) It has been revealed that hardened ploughshares that have passed field tests are subject to lower wear rates compared to non-hardened ones. It was found that when operating time is 24.785 hectares per ploughshare, the wear of the linear size of the cutting edge along the width of hardened ploughshares is on average up to 10-11 millimeters less than that of non-hardened ones. It was found that when processing 228 hectares, the wear of the linear size of the cutting edge along the width of hardened bits is on average up to 9-10 millimeters less than that of non-hardened ones. (Conclusions) The technology of surfacing with intermittent wear-resistant rollers provides an increase in the efficiency of hardening of Kverneland working bodies according to the criterion of wear resistance by an average of 20-30 percent. The adjusted technological parameters of the surfacing process will reduce the wear rate and increase the service life of the blade part of the working bodies, as well as reduce the amount of surfaced material by an average of 60 percent. The continuation of work on strengthening the working bodies should be aimed at changing the surfacing scheme and choosing a cheaper domestic cored wire.

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Publicly auditable conditional blind signatures

Journal of Computer Security ◽

10.3233/jcs-181270 ◽

2021 ◽

Vol 29 (2) ◽

pp. 229-271

Author(s):

Panagiotis Grontas ◽

Aris Pagourtzis ◽

Alexandros Zacharakis ◽

Bingsheng Zhang

Keyword(s):

Proof Of Concept ◽

Equivalence Test ◽

Zero Knowledge ◽

Private Key ◽

Blind Signatures ◽

Cryptographic Primitive ◽

Security Properties ◽

Designated Verifier

This work formalizes Publicly Auditable Conditional Blind Signatures (PACBS), a new cryptographic primitive that allows the verifiable issuance of blind signatures, the validity of which is contingent upon a predicate and decided by a designated verifier. In particular, when a user requests the signing of a message, blinded to protect her privacy, the signer embeds data in the signature that makes it valid if and only if a condition holds. A verifier, identified by a private key, can check the signature and learn the value of the predicate. Auditability mechanisms in the form of non-interactive zero-knowledge proofs are provided, so that a cheating signer cannot issue arbitrary signatures and a cheating verifier cannot ignore the embedded condition. The security properties of this new primitive are defined using cryptographic games. A proof-of-concept construction, based on the Okamoto–Schnorr blind signatures infused with a plaintext equivalence test is presented and its security is analyzed.

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An access control model for the Internet of Things based on zero-knowledge token and blockchain

EURASIP Journal on Wireless Communications and Networking ◽

10.1186/s13638-021-01986-4 ◽

2021 ◽

Vol 2021 (1) ◽

Author(s):

Lihua Song ◽

Xinran Ju ◽

Zongke Zhu ◽

Mengchen Li

Keyword(s):

Internet Of Things ◽

Access Control ◽

Single Point ◽

Control Model ◽

Third Party ◽

Security Level ◽

Zero Knowledge ◽

Access Control Model ◽

Test Analysis ◽

Zero Knowledge Proof

AbstractInformation security has become a hot topic in Internet of Things (IoT), and traditional centralized access control models are faced with threats such as single point failure, internal attack, and central leak. In this paper, we propose a model to improve the access control security of the IoT, which is based on zero-knowledge proof and smart contract technology in the blockchain. Firstly, we deploy attribute information of access control in the blockchain, which relieves the pressure and credibility problem brought by the third-party information concentration. Secondly, encrypted access control token is used to gain the access permission of the resources, which makes the user's identity invisible and effectively avoids attribute ownership exposure problem. Besides, the use of smart contracts solves the problem of low computing efficiency of IoT devices and the waste of blockchain computing power resources. Finally, a prototype of IoT access control system based on blockchain and zero-knowledge proof technology is implemented. The test analysis results show that the model achieves effective attribute privacy protection, compared with the Attribute-Based Access Control model of the same security level, the access efficiency increases linearly with the increase of access scale.

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PipeZK: Accelerating Zero-Knowledge Proof with a Pipelined Architecture

2021 ACM/IEEE 48th Annual International Symposium on Computer Architecture (ISCA) ◽

10.1109/isca52012.2021.00040 ◽

2021 ◽

Author(s):

Ye Zhang ◽

Shuo Wang ◽

Xian Zhang ◽

Jiangbin Dong ◽

Xingzhong Mao ◽

...

Keyword(s):

Zero Knowledge ◽

Pipelined Architecture ◽

Zero Knowledge Proof

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Implementation Framework for a Blockchain-Based Federated Learning Model for Classification Problems

Symmetry ◽

10.3390/sym13071116 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1116

Author(s):

Zeba Mahmood ◽

Vacius Jusas

Keyword(s):

Machine Learning ◽

Learning Model ◽

Global Perspective ◽

Learning Technology ◽

Classification Problems ◽

Zero Knowledge ◽

Privacy And Security ◽

Implementation Framework ◽

The Past

This paper introduces a blockchain-based federated learning (FL) framework with incentives for participating nodes to enhance the accuracy of classification problems. Machine learning technology has been rapidly developed and changed from a global perspective for the past few years. The FL framework is based on the Ethereum blockchain and creates an autonomous ecosystem, where nodes compete to improve the accuracy of classification problems. With privacy being one of the biggest concerns, FL makes use of the blockchain-based approach to ensure privacy and security. Another important technology that underlies the FL framework is zero-knowledge proofs (ZKPs), which ensure that data uploaded to the network are accurate and private. Basically, ZKPs allow nodes to compete fairly by only submitting accurate models to the parameter server and get rewarded for that. We have conducted an analysis and found that ZKPs can help improve the accuracy of models submitted to the parameter server and facilitate the honest participation of all nodes in FL.

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