A Framework for Enhancing Privacy and Anonymity in Blockchain-Enabled IoT Devices

With the increase in IoT(Internet of Things)devices comes an inherent challenge of security.In the world today,privacy is the prime concern of every individual.Preserving one’s privacy and keeping anonymity throughout the system is a desired functionality that does not come without inevitable trade-offs like scalability and increased complexity and is always exceedingly difficult to manage.The challenge is keeping confidentiality and continuing to make the person innominate throughout the system.To address this,we present our proposed architecture where we manage IoT devices using blockchain technology.Our proposed architecture works on and off blockchain integrated with the closed-circuit television(CCTV)security camera fixed at the rental property.In this framework,the CCTV security camera feed is redirected towards the owner and renter based on the smart contract conditions.One entity(owner or renter)can see the CCTV security camera feed at one time.There is no third-party dependence except for the CCTV security camera deployment phase.Our contributions include the proposition of framework architecture,a novel smart contract algorithm,and the modification to the ring signatures leveraging an existing cryptographic technique.Analyses are made based on different systems’security and key management areas.In an empirical study,our proposed algorithm performed better in key generation,proof generation,and verification times.By comparing similar existing schemes,we have shown the proposed architectures’advantages.Until now,we have developed this system for a specific area in the real world.However,this system is scalable and applicable to other areas like healthcare monitoring systems,which is part of our future work.

Analysing the Social Media Momo Phenomenon:Causes and Effects

The“Momo Army”is an anonymous group on social media platforms like Douban and Xiaohongshu.It uses similar avatars and nicknames to demonstrate collective identity and engage in group interactions.This group rapidly forms a strong network of interaction,establishing stable group relationships,and achieving digital invisibility.However,anonymous groups conceal anonymous violence and cyberbullying,negatively affecting individuals and society.This study will explore the reasons for the emergence of such groups,self-presented characteristics of their group members,and social impacts.It will conduct in-depth research and analysis through participant observation and interviews.

网络中多敏感属性数据发布隐私保护研究

随着网络技术的快速发展,许多社会网站被创建和使用,使得关于个人的社会网络信息大量被收集和发布.为了保证个人隐私的安全,本文提出了一个新的集值属性(k,l)anonymity隐私原则,开发了一个满足这个隐私原则的隐私算法来高效地处理集值属性数据流。并通过实验进行了验证本算法的高效率和有效性。

Double-Blockchain Assisted Secure and Anonymous Data Aggregation for Fog-Enabled Smart Grid

As a future energy system,the smart grid is designed to improve the efficiency of traditional power systems while providing more stable and reliable services.However,this efficient and reliable service relies on collecting and analyzing users’electricity consumption data frequently,which induces various security and privacy threats.To address these challenges,we propose a double-blockchain assisted secure and anonymous data aggregation scheme for fog-enabled smart grid named DA-SADA.Specifically,we design a three-tier architecture-based data aggregation framework by integrating fog computing and the blockchain,which provides strong support for achieving efficient and secure data collection in smart grids.Subsequently,we develop a secure and anonymous data aggregation mechanism with low computational overhead by jointly leveraging the Paillier encryption,batch aggregation signature and anonymous authentication.In particular,the system achieves fine-grained data aggregation and provides effective support for power dispatching and price adjustment by the designed double-blockchain and two-level data aggregation.Finally,the superiority of the proposed scheme is illustrated by a series of security and computation cost analyses.

Achieve Personalized Anonymity Through Query Blocks Exchanging

In cyberspace security,the privacy in location-based services(LBSs) becomes more critical. In previous solutions,a trusted third party(TTP) was usually employed to provide disturbance or obfuscation,but it may become the single point of failure or service bottleneck. In order to cope with this drawback,we focus on another important class,establishing anonymous group through short-range communication to achieve k-anonymity with collaborative users. Along with the analysis of existing algorithms,we found users in the group must share the same maximum anonymity degree,and they could not ease the process of preservation in a lower one. To cope with this problem,we proposed a random-QBE algorithm to put up with personalized anonymity in user collaboration algorithms,and this algorithm could preserve both query privacy and location privacy. Then we studied the attacks from passive and active adversaries and used entropy to measure user's privacy level. Finally,experimental evaluations further verify its effectiveness and efficiency.

Privacy preservation in permissionless blockchain:A survey

Permissionless blockchain,as a kind of distributed ledger,has gained considerable attention because of its openness,transparency,decentralization,and immutability.Currently,permissionless blockchain has shown a good application prospect in many fields,from the initial cryptocurrency to the Internet of Things(IoT)and Vehicular Ad-Hoc Networking(VANET),which is considered as the beginning of rewriting our digital infrastructure.However,blockchain confronts some privacy risks that hinder its practical applications.Though numerous surveys reviewed the privacy preservation in blockchain,they failed to reveal the latest advances,nor have they been able to conduct a unified standard comprehensive classification of the privacy protection of permissionless blockchain.Therefore,in this paper,we analyze the specific characteristics of permissionless blockchain,summarize the potential privacy threats,and investigate the unique privacy requirements of blockchain.Existing privacy preservation technologies are carefully surveyed and evaluated based on our proposed evaluation criteria.We finally figure out open research issues as well as future research directions from the perspective of privacy issues.

To name or not to name？ An overview of the social and ethical issues raised by removing anonymity from sperm donors

The aim of this paper is to focus on the ethical issues raised by the removal of anonymity from sperm donors. The increasing currency of a ＇right to genetic truth＇ is clearly visible in the drive to revise the legislation on donor anonymity in Western and European countries. The ethical debate is polarized between the ＇right to privacy＇ of the donor or parent and the ＇right to know＇ of the prospective child. However, it is evident that religious, social and cultural attitudes have an overarching impact on attitudes towards sperm donation generally and anonymity specifically. In Asian countries, the social and cultural heritage is hugely diverse and different from those of the West. This review considers the research exploring the complexity of ethical issues informing this debate, and argues that parent＇s decisions to reveal donor insemination origins to their children are highly complex and relate to a range of social and cultural attitudes that have not been addressed within the policy to remove anonymity from sperm donors.

A New Anonymity Model for Privacy-Preserving Data Publishing

Privacy-preserving data publishing （PPDP） is one of the hot issues in the field of the network security. The existing PPDP technique cannot deal with generality attacks, which explicitly contain the sensitivity attack and the similarity attack. This paper proposes a novel model, （w,γ, k）-anonymity, to avoid generality attacks on both cases of numeric and categorical attributes. We show that the optimal （w, γ, k）-anonymity problem is NP-hard and conduct the Top-down Local recoding （TDL） algorithm to implement the model. Our experiments validate the improvement of our model with real data.

A Fair Blind Signature Scheme to Revoke Malicious Vehicles in VANETs

With the rapid development of IoT(Internet of Things),VANETs(Vehicular Ad-Hoc Networks)have become an attractive ad-hoc network that brings convenience into people’s lives.Vehicles can be informed of the position,direction,speed and other real-time information of nearby vehicles to avoid traffic jams and accidents.However,VANET environments could be dangerous in the absence of security protection.Because of the openness and self-organization of VANETs,there are plenty of malicious pathways.To guarantee vehicle security,the research aims to provide an effective VANET security mechanism that can track malicious vehicles as necessary.Therefore,this work focuses on malicious vehicles and proposes an anonymous authentication scheme in VANETs based on the fair blind signature to protect vehicle security.

Security Enhancement of Robust User Authentication Framework for Wireless Sensor Networks

In order to relvedy the security weaknesses of a robust user authentication framework for wireless sensor networks, an enhanced user authentication framework is presented. The enhanced scheme requires proof of the possession of both a password and a snort card, and provides more security guarantees in two aspects： 1） it addresses the untmceability property so that any third party accessing the communication channel cannot link two authentication sessions originated from the same user, and 2） the use of a smart card prevents offiine attacks to guess passwords. The security and efficiency analyses indicate that our enhanced scheme provides the highest level of security at reasonable computational costs. Therefore, it is a practical authentication scheme with attractive security features for wireless sensor networks.

A Novel Anonymous Authentication Scheme Based on Edge Computing in Internet of Vehicles

The vehicular cloud computing is an emerging technology that changes vehicle communication and underlying trafc management applications.However,cloud computing has disadvantages such as high delay,low privacy and high communication cost,which can not meet the needs of realtime interactive information of Internet of vehicles.Ensuring security and privacy in Internet of Vehicles is also regarded as one of its most important challenges.Therefore,in order to ensure the user information security and improve the real-time of vehicle information interaction,this paper proposes an anonymous authentication scheme based on edge computing.In this scheme,the concept of edge computing is introduced into the Internet of vehicles,which makes full use of the redundant computing power and storage capacity of idle edge equipment.The edge vehicle nodes are determined by simple algorithm of dening distance and resources,and the improved RSA encryption algorithm is used to encrypt the user information.The improved RSA algorithm encrypts the user information by reencrypting the encryption parameters.Compared with the traditional RSA algorithm,it can resist more attacks,so it is used to ensure the security of user information.It can not only protect the privacy of vehicles,but also avoid anonymous abuse.Simulation results show that the proposed scheme has lower computational complexity and communication overhead than the traditional anonymous scheme.

Pathogenesis and managenent of pain in chronic pancreatitis

INTRODUCTIONOf the three cardinal manifestations of chronic pancreatitis-pain,diabetes mellitus and steatorrhea,it is pain thatbrings the patient to the physician and is the most difficultto manage.The intractabale pain that is quite

A Novel Direct Anonymous Attestation Protocol Based on Zero Knowledge Proof for Different Trusted Domains

In order to solve the issue that existing direct anonymous attestation (DAA) scheme can not operate effectively in different domains,based on the original DAA scheme,a novel direct anonymous attestation protocol used in multi domains environment is proposed and designed,in which,the certificate issuer located in outside of domain can be considered as a proxy server to issue the DAA certificate for valid member nodes directly.Our designed mechanism accords with present trusted computing group (TCG) international specification,and can solve the problems of practical authentication and privacy information protection between different trusted domains efficiently.Compared with present DAA scheme,in our protocol,the anonymity,unforgeability can be guaranteed,and the replay-attack also can be avoided.It has important referenced and practical application value in trusted computing field.

Multi-Candidate Voting Model Based on Blockchain

Electronic voting has partially solved the problems of poor anonymity and low efficiency associated with traditional voting.However,the difficulties it introduces into the supervision of the vote counting,as well as its need for a concurrent guaranteed trusted third party,should not be overlooked.With the advent of blockchain technology in recent years,its features such as decentralization,anonymity,and non-tampering have made it a good candidate in solving the problems that electronic voting faces.In this study,we propose a multi-candidate voting model based on the blockchain technology.With the introduction of an asymmetric encryption and an anonymity-preserving voting algorithm,votes can be counted without relying on a third party,and the voting results can be displayed in real time in a manner that satisfies various levels of voting security and privacy requirements.Experimental results show that the proposed model solves the aforementioned problems of electronic voting without significant negative impact from an increasing number of voters or candidates.

AABN: Anonymity Assessment Model Based on Bayesian Network With Application to Blockchain

Blockchain is a technology that uses community validation to keep synchronized the content of ledgers replicated across multiple users,which is the underlying technology of digital currency like bitcoin.The anonymity of blockchain has caused widespread concern.In this paper,we put forward AABN,an Anonymity Assessment model based on Bayesian Network.Firstly,we investigate and analyze the anonymity assessment techniques,and focus on typical anonymity assessment schemes.Then the related concepts involved in the assessment model are introduced and the model construction process is described in detail.Finally,the anonymity in the MIX anonymous network is quantitatively evaluated using the methods of accurate reasoning and approximate reasoning respectively,and the anonymity assessment experiments under different output strategies of the MIX anonymous network are analyzed.

Security Enhanced Anonymous User Authenticated Key Agreement Scheme Using Smart Card

Nowadays, the password-based remote user authentication mechanism using smart card is one of the simplest and convenient authentication ways to ensure secure communications over the public network environments. Recently, Liu et al. proposed an efficient and secure smart card based password authentication scheme. However, we find that Liu et al.’s scheme is vulnerable to the off-line password guessing attack and user impersonation attack. Furthermore, it also cannot provide user anonymity. In this paper, we cryptanalyze Liu et al.’s scheme and propose a security enhanced user authentication scheme to overcome the aforementioned problems. Especially, in order to preserve the user anonymity and prevent the guessing attack, we use the dynamic identity technique. The analysis shows that the proposed scheme is more secure and efficient than other related authentication schemes.

A Method to Implement Full Anonymous Attestation for Trusted Computing Platform

Trusted computing （TC） technology is brought out by trusted computing group （TCG） to make computing as safe and reliable as people expect. Attestation is one main function specified by TCG, which is the means by which a trusted computer assures a remote computer whose platform is not tampered with. There are two protocols that implement attestation without disclosing the platform＇s real identity, which are Privacy CA-based protocol and direct anonymous attestation （DAA） protocol. However, in the first protocol the privacy CA is the bottleneck and the platform＇s identity will be disclosed if the privacy CA is compromise, while DAA protocol can do profiling when dealing with rogue hardware device. In this paper, we propose a DAA-extended new approach to ensure full anonymous attestation that can not only detect a rogue TPM, but also reveal rogue TPM＇s real identity.

An Enhanced Direct Anonymous Attestation Scheme with Mutual Authentication for Network-Connected UAV Communication Systems

In network-connected UAV(NCUAV) communication systems, user authentication is replaced by platform identity authentication and integrity check because many NC-UAVs are operated without human intervention. Direct anonymous attestation(DAA) is an attractive cryptographic scheme that provides an elegant balance between platform authentication and anonymity. However, because of the low-level computing capability and limited transmission bandwidth in UAV, the existing DAA schemes are not suitable for NC-UAV communication systems. In this paper, we propose an enhanced DAA scheme with mutual authentication(MA-DAA scheme), which meets the security requirements of NC-UAV communication systems. The proposed MA-DAA scheme, which is based on asymmetric pairings, bundles the identities of trusted platform module(TPM) and Host to solve the malicious module changing attacks. Credential randomization, batch proof and verification, and mutual authentication are realized in the MA-DAA scheme. The computational workload in TPM and Host is reduced in order to meet the low computation and resource requirements in TPM and Host.The entire scheme and protocols are presented,and the security and efficiency of the proposed MA-DAA scheme are proved and analyzed.Our experiment results also confirm the high efficiency of the proposed scheme.

Anonymous multipath routing protocol based on secret sharing in mobile ad hoc networks

Because the intrinsic characteristics of mobile ad hoc networks（MANETs） cause several vulnerabilities,anonymous routing protocols attract much more attention in secure mobile ad hoc networks for the purposes of security and privacy concerns.Until recently,lots of anonymous routing protocols have been proposed.However,most of them are single path or use one path at a time,and the multipath schemes can not thwart both the passive attacks and active attacks simultaneously.Thus an anonymous multipath routing protocol based on secret sharing is proposed.The protocol provides identity anonymity,location anonymity,data and traffic anonymity by employing cryptograph technology and secret sharing in MANET communication process.Meanwhile,a hash function is introduced to detect active attacks in the data transmission process.The protocol can effectively thwart various passive attacks and reduce the successful probability of active attacks（such as interception and physical destroy attacks）.Simulation results show that the proposed scheme provides a reasonably good level of network security and performance.

A Sensor Anonymity Enhancement Scheme Based on Pseudonym for Clustered Wireless Sensor Network

Security problem is an important issue for Wireless Sensor Network.The paper focuses on the privacy protection of WSN applications.An anonymity enhancement tactic based on pseudonym mechanism is presented for clustered Wireless Sensor Network,which provides anonymity for both the sensors within a cluster and the cluster head nodes.Simulation experiments are launched through NS2 platform to validate the anonymity performance.The theoretical analysis and empirical study imply that the proposed scheme based on pseudonym can protect the privacies of both the sensor nodes and the cluster head nodes.The work is valuable and the experimental results are convincible.