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.     

无线网络安全的脆弱性、威胁与对策分析

无线网络给网络社会提供了许多便捷,但随之而来的是新的安全威胁和风险。技术上可以解决应对无线安全威胁和漏洞,但更需关注的是网络的管理问题。无线网络的管理需要一个健全的风险评估环境和发展计划。文章提出了一个框架,以帮助管理人员了解和评估无线技术使用中面临的各种威胁,并提出了一些可用的应对威胁的解决方案。     

A survey on jamming attacks and countermeasures in WSNs

Jamming represents the most serious security threat in the field of Wireless Sensor Networks (WSNs), as it can easily put out of order even WSNs that utilize strong highlayer security mechanisms, simply because it is often ignored in the initial WSN design. The objective of this article is to provide a general overview of the critical issue of jamming in WSNs and cover all the relevant work, providing the interested researcher pointers for open research issues in this field. We provide a brief overview of the communication protocols typically used in WSN deployments and highlight the characteristics of contemporary WSNs, that make them susceptible to jamming attacks, along with the various types of jamming which can be exercised against WSNs. Common jamming techniques and an overview of various types of jammers are reviewed and typical countermeasures against jamming are also analyzed. The key ideas of existing security mechanisms against jamming attacks in WSNs are presented and open research issues, with respect to the defense against jamming attacks are highlighted.     

区块链网络安全保障:攻击与防御

随着区块链技术的迅猛发展,区块链系统的安全问题正逐渐暴露出来,给区块链生态系统带来巨大风险.通过回顾区块链安全方面的相关工作,对区块链潜在的安全问题进行了系统的研究.将区块链框架分为数据层、网络层、共识层和应用层4层,分析其中的安全漏洞及攻击原理,并讨论了增强区块链安全的防御方案.最后,在现有研究的基础上展望了区块链安...     

Recent advances in consensus protocols for blockchain: a survey

Wireless Networks - As the core of a blockchain system, the consensus mechanism not only helps to maintain the consistency of node data, but also gets involved in the issuance of tokens and...     

Silver bullets and cybersecurity

Within 24 hours in November 2002, a British hacker was indicted by the US justice Department for breaking into military and NASA computer systems and the US Congress passed a bill that funded $903 million for computer security initiatives (Wired.com, 14 Nov. 2002). Meanwhile, nearly every multimedia conference since 11 September 2001 has discussed the need for increased computer security, both in the public and private sector. Is this burgeoning field all hype? It seems that although some hype exists, the fears are warranted. On one hand, terrorists and "hacktivists" have employed various means to attack or shut down government sites since the Web's inception. On the other hand, despite grave warnings by the US government and security companies, we have not really seen great dangers of cyberterrorism in the private sector. What we have seen, however, is an increase in general hackers attacking the public and private sector either to prove they can, to cause aggravation, or for financial gain. The paper discusses basis security concerns, event management software and intrusion detection.     

Web of cybersecurity: Linking,locating, and discovering structured cybersecurity information

Cybersecurity is one of the main concerns of many organizations today, and accessibility to cybersecurity information in a timely manner is crucial to maintaining cybersecurity. Various repositories of cybersecurity‐related information are publicly available on the Internet. However, users are unaware of many of them, and it is impractical for them to keep track of all of them. Cybersecurity information stored in these repositories must be able to be located and accessed by the parties who need it. To address this issue, this paper proposes a mechanism of linking, locating, and discovering various cybersecurity information to improve its accessibility in a timely manner. This mechanism allows us to locate various cybersecurity information having different schemata by generating metadata with which a list of cybersecurity information is managed. The information structure incorporated in this mechanism is unique, and it makes our mechanism flexible and extensible. The structure consists of categories and formats that are linked to each other. The mechanism can propagate information updates to minimize the risk of obsolete information. This paper also introduces a prototype of the mechanism to demonstrate its feasibility, and it analyzes the mechanism's extensibility, scalability, and information credibility. Through this study, we aim to improve the accessibility of cybersecurity information on the Internet and facilitate information sharing beyond organizational borders, with the eventual goal of creating a web of cybersecurity.     

A survey of possible passive antenna applications ofhigh-temperature superconductors

A survey of possible applications of high-temperature superconductors (HTSs) to antennas and antenna feed networks is presented. The frequency range considered is 1 MHz for 100 GHz. Three antenna application areas seem appropriate for HTS material: electrically small antennas and their matching networks; feed and matching networks for compact arrays with enhanced directive gain (superdirective arrays); and feed networks for millimeter-wave arrays. Preliminary experimental results are presented on YBaCuO and TlBaCaCuO 500 MHz half-loop antennas that show an increase in radiation efficiency (compared with a copper antenna at the same temperature) by a factor of 5 for the HTS antennas     

Parallel and distributed computing for cybersecurity

Parallel and distributed data mining offer great promise for addressing cybersecurity. The Minnesota Intrusion Detection System can detect sophisticated cyberattacks on large-scale networks that are hard to detect using signature-based systems.     

一种基于匹配的Android系统漏洞检测方法

目前Android系统占领了智能移动操作系统的绝大多数份额,然而Android系统的安全问题却令人忧虑,近年来频频爆出高危漏洞,给广大Android用户带来了很大的安全隐患。对Android系统漏洞检测进行了研究,提出了一种基于匹配的快速检测Android系统漏洞的方法,同时设计和实现了一个基于脚本的漏洞扫描工具。实验表明,该工具可有效检测Android系统漏洞,运行效果良好。     

Consistency,availability, and partition tolerance in blockchain: a survey on the consensus mechanism over peer-to-peer networking

Annals of Telecommunications - Blockchain is a disruptive technology that relies on the distributed nature of the peer-to-peer network while performing an agreement, or consensus, a mechanism to...     

Survey of the intelligent and connected vehicle cybersecurity

Cyber attacks on vehicles not only cause privacy leaks and economic losses but also endanger human life and even rise to national public safety issues.Therefore,the research on the cybersecurity of intelligent and connected vehicle (ICV) has become a research hot spot.Firstly,the structural status and characteristics of the in-vehicle network (IVN) in ICV were introduced,and the challenges and constraints of cybersecurity enhancement design for IVN were also presented.Secondly,focusing on the current functional safety and cybersecurity issues of IVN,a survey of the current cybersecurity enhancement researches for IVN was conducted.Finally,according to the characteristics of the IVN structure,some important research directions and suggestions about cybersecurity problems of ICV were pointed out from the three aspects of standard construction,functional safety and cybersecurity.     

基于区块链的智能电网监控

随着智能电网系统的广泛应用,电力公司可以通过网络获取实时用电数据以满足负荷预测以及电力营销等业务需求,电力用户也可及时得知当月电费,甚至了解何时用电量较大以及哪个电器耗电量最大等具体细节,但这也导致了数据泄露的风险。为此文中利用主权区块链技术和智能合约的实施,为电力公司和电力用户之间提供一个可信任系统,使得电力供需双方都能安全、透明地获取用电数据。     

浅析计算机网络安全的漏洞及防范

信息化程度越来越高在给人们的日常生活及工作带来便利的同时,也容易引发一系列的安全隐患问题。在信息化时代背景下,随着计算机网络的普及,所涉及的行业领域越来越广,计算机网络逐渐成为现代社会生产和发展过程中不可或缺的重要组成部分。但是过于依赖于计算机网络,也同样为各个行业带来了诸多隐患。计算机网络安全漏洞的出现,必然会对计算机网络的安全运行造成极大影响,如果不采取有效的防范措施,就会造成网络系统遭受破坏或信息泄露等一系列问题。文章就计算机网络安全漏洞进行简要分析,并在此基础上对其有效的防范措施进行深入探讨,希望能够为我国计算机网络系统的安全带来一定保障作用。     

基于区块链的可信数据交换技术与应用

基于区块链的可信数据交换技术能实现去中心化网络中隐私数据的保护与流通,推动数字化时代打破“数据孤岛”壁垒。分析了可信数据交换的背景和需求,阐述了基于区块链可信数据交换及其关键技术,并结合区块链底层基础设施平台展示了应用情况。     

基于区块链技术的可信网络

随着网络安全问题不断频发,传统补丁式外置安全方案已经不能满足业界需求,产业各方更希望从网络架构层实现内生安全,因此提出了去中心化可信网络架构。在研究现有网络底层协议安全的基础上,提出了基于去中心化技术/区块链技术的可信网络的架构方案,能够有效地解决现有网络缺乏内生安全的问题,并在中国下一代互联网（China’s Next Generation Internet,CNGI）进行了验证。此方案从协议层实现了网络安全,避免恶意网络攻击或者因配置失误造成的网络故障。     

A systematic literature review of blockchain cyber security

Since the publication of Satoshi Nakamoto's white paper on Bitcoin in 2008, blockchain has (slowly) become one of the most frequently discussed methods for securing data storage and transfer through decentralized, trustless, peer-to-peer systems. This research identifies peer-reviewed literature that seeks to utilize blockchain for cyber security purposes and presents a systematic analysis of the most frequently adopted blockchain security applications. Our findings show that the Internet of Things (IoT) lends itself well to novel blockchain applications, as do networks and machine visualization, public-key cryptography, web applications, certification schemes and the secure storage of Personally Identifiable Information (PII). This timely systematic review also sheds light on future directions of research, education and practices in the blockchain and cyber security space, such as security of blockchain in IoT, security of blockchain for AI data, and sidechain security.     

Research on cross-chain and interoperability for blockchain system

At present, there is an urgent need for blockchain interoperability technology to realize interconnection between various blockchains, data communication and value transfer between blockchains, so as to break the ‘ value silo’ phenomenon of each blockchain. Firstly, it lists what people understand about the concept of interoperability. Secondly, it gives the key technical issues of cross-chain, including cross-chain mechanism, interoperability, eventual consistency, and universality. Then, the implementation of each cross-chain key technology is analyzed, including Hash-locking, two-way peg, notary schemes, relay chain scheme, cross-chain protocol, and global identity system. Immediately after that, five typical cross-chain systems are introduced and comparative analysis is made. In addition, two examples of cross-chain programmability and their analysis are given. Finally, the current state of cross-chain technology is summarized from two aspects: key technology implementation and cross-chain application enforcement. The cross-chain technology as a whole has formed a centralized fixed mechanism, as well as a trend of modular design, and some of the solutions to mature applications were established in the relevant standards organizations, and the cross-chain technology architecture tends to be unified, which is expected to accelerate the evolution of the open cross-chain network that supports the real needs of the interconnection of all chains.     

Standards with cybersecurity controls for smart grid—A systematic analysis

In recent years, numerous standards related to the cybersecurity of smart grids have been published, which led to the challenge for operators in obtaining indications that match their specific objectives and contexts. Although several studies approached this problem by providing more or less comprehensive surveys and overviews of smart grid cybersecurity standards, none of them was dedicated to the actual and important subject of cybersecurity controls. This paper aims at filling this gap. A systematic literature analysis was conducted which resulted in the identification of 19 broadly recognised standards that specify cybersecurity controls applicable to the smart grid infrastructure. The publications are described in respect to the controls they define and referred to evaluation criteria. In result, this paper constitutes a guideline on standardised cybersecurity controls for smart grids, where (criteria‐based) indications help to select standards for a particular smart grid area or specific goals. The method of the research as well as the standards' selection and evaluation criteria are presented.