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The mobile software agent paradigm provides a generic, customisable foundation for the development of high performance distriubuted applications. An efficient, general‐purpose access control mechanism is required to support the development of a wide range of applications. This is achievable if the design of the access control system is based on the principles of simplicity, programmability (customisation) and reusability. However, existing mobile agent architectures either neglect this issue, or offer centralised schemes that do not support adaptive access control on a per‐agent basis and do not address the issues of secure knowledge sharing and reusing. In this paper a simple, distributed access control architecture is presented, based on the concept of distributed, active authorisation entities (lock cells), any combination of which can be referenced by an agent to provide input and/or output access control. It is demonstrated how these lock cells can be used to implement security domains and how they can be combined to create composite lock cells.

Presents a new model for resource discovery in grids and peer‐to‐peer networks designed to utilise efficiently small numbers of messages for query processing and building of the network. Outlines and evaluates the model through a theoretical comparison with other resource discovery systems and a mathematical analysis of the number of messages utilised in contrast with Chord, a distributed hash table. Shows that through careful setting of parameter values the model is able to provide responses to queries and node addition in fewer messages than Chord. The model is shown to have significant benefits over other peer‐to‐peer networks reviewed. Uses a case study to show the applicability of the model as a methodology for building resource discovery systems in peer‐to‐peer networks using different underlying structures. Shows a promising new method of creating a resource discovery system by building a timeline structure on demand, which will be of interest to both researchers and system implementers in the fields of grid computing, peer‐to‐peer networks and distributed resource discovery in general.

The purpose of this paper is to propose a model for sharing network capacity on demand among different underloaded and overloaded P2P ROME‐enabled networks. The paper aims to target networks of nodes with highly dynamic workload fluctuations that may experience a burst of traffic and/or massive nodes' failure rates.

The paper shows that when locally available network capacity is not adequate for the workload requirements, the excessive capacity needs to be sought into other networks with more availability. A random flat P2P overlay of the ROME servers is used for the discovery and movement of nodes between two networks. Centralised or decentralised DHT‐based directories of available nodes cannot cope with high workload fluctuations and frequent join/leave actions of nodes. The paper also introduces semantics to refine the answers to the ones with the most appropriate nodes for the requesting network and to find the requested capacity faster and more efficiently. The behaviour of the model is simulated to evaluate with several experiments the model based on some metrics.

The paper finds that all the user queries of an overloaded underlying network are dropped if G‐ROME is not used but as G‐ROME overlay satisfies the requested capacity of a ROME server, its Chord ring size increases. In case of uniformly distributed and/or plentiful capacity over the overlay, shallow searches may give very good results. On the contrary, deeper searches are required for scarce capacity but the number of messages increases almost exponentially.

This paper provides a model for moving the required resources to the requesting job environment rather than the job and its context to the resource.

Nowadays, more interest is found among the researchers in MANETs in practical and theoretical areas and their performance under various environments. WSNs have begun to combine with the IoT via the sensing capability of Internet-connected devices and the Internet access ability of sensor nodes. It is essential to shelter the network from attacks over the Internet by keeping the secure router.

This paper plans to frame an effective literature review on diverse intrusion detection and prevention systems in Wireless Sensor Networks (WSNs) and Mobile Ad hoc NETworks (MANETs) highly suitable for security in Internet of Things (IoT) applications. The literature review is focused on various types of attacks concentrated in each contribution and the adoption of prevention and mitigation models are observed. In addition, the types of the dataset used, types of attacks concentrated, types of tools used for implementation, and performance measures analyzed in each contribution are analyzed. Finally, an attempt is made to conclude the review with several future research directions in designing and implementing IDS for MANETs that preserve the security aspects of IoT.

It observed the different attack types focused on every contribution and the adoption of prevention and mitigation models. Additionally, the used dataset types, the focused attack types, the tool types used for implementation, and the performance measures were investigated in every contribution.

This paper presents a literature review on diverse contributions of attack detection and prevention, and the stand of different machine learning and deep learning models along with the analysis of types of the dataset used, attacks concentrated, tools used for implementation and performance measures on the network security for IoT applications.

With digital spaces an increasing feature of our everyday lives, and the internet now a primary means of sourcing IPEDs and information regarding their use, this chapter seeks to understand how digital fitness forum communities shape the dissemination of culturally embedded harm reduction advice. Findings are drawn from two netnographic studies of fitness forums, which identify several key areas in which community norms and structures served to inform harm reduction behaviours. This included embedded forum reputation systems and the ways in which these shaped IPED access, including through elevating ‘expert’ users and encouraging informed discussion regarding product quality, to the emergence of steroid testing services from forums as a community harm reduction tool. Second, forums were observed to often encourage users to conduct research and inform themselves regarding safe use, though limitations to this norm were also documented in relation to poor-quality medical advice, highlighting the issues with IPED users' reliance on anecdotal advice in the contexts of prohibition. Finally, the role of digital fitness forums as ‘digital backstage’ is considered, examining both how this can be harmful to IPED users from excluded or ‘otherised’ groups, but simultaneously offers cultural participants the opportunity for airing vulnerabilities in a space where their masculine identity is not threatened in doing so, thus facilitating harm reduction among cultural ‘insiders’.

This study aims to explore the key challenges and drawbacks of smart contracts (SCs) and how they impact digital resilience within small and medium enterprises (SMEs). Whilst this type of technology is seen as a step forward in terms of traceability, transparency and immutability to increase digital resilience, we argue that it should be approached with trepidation.

In developing this paper, the authors conduct a systematic literature search using the Scopus database. Through this, we identified 931 relevant articles, of which 30 were used as the focus of this article. Thematic analysis was used as the analytical approach to develop themes and meaning from the data.

In this paper, there is an emphasis on the importance of understanding the potential risks associated with SC implementation, as well as identifying appropriate strategies for mitigating any negative impact. In our findings, we puts forward three key themes, namely legality, security and human error, which we argue are key smart contract challenges that impact SME digital resilience.

In this paper, we propose the notion of “centralised control in decentralised solutions”. This comes from the research highlighting SC weaknesses in digital resilience for SMEs. We argue that there is a need for standards, regulations and legislation to address these issues, advocating, ironically, a centralised approach to decentralised technology.

The purpose of this paper is to employ the case of Organization for Economic Cooperation and Development (OECD) data repositories to examine the potential of blockchain technology in the context of addressing basic contemporary societal concerns, such as transparency, accountability and trust in the policymaking process. Current approaches to sharing data employ standardized metadata, in which the provider of the service is assumed to be a trusted party. However, derived data, analytic processes or links from policies, are in many cases not shared in the same form, thus breaking the provenance trace and making the repetition of analysis conducted in the past difficult. Similarly, it becomes tricky to test whether certain conditions justifying policies implemented still apply. A higher level of reuse would require a decentralized approach to sharing both data and analytic scripts and software. This could be supported by a combination of blockchain and decentralized file system technology.

The findings presented in this paper have been derived from an analysis of a case study, i.e., analytics using data made available by the OECD. The set of data the OECD provides is vast and is used broadly. The argument is structured as follows. First, current issues and topics shaping the debate on blockchain are outlined. Then, a redefinition of the main artifacts on which some simple or convoluted analytic results are based is revised for some concrete purposes. The requirements on provenance, trust and repeatability are discussed with regards to the architecture proposed, and a proof of concept using smart contracts is used for reasoning on relevant scenarios.

A combination of decentralized file systems and an open blockchain such as Ethereum supporting smart contracts can ascertain that the set of artifacts used for the analytics is shared. This enables the sequence underlying the successive stages of research and/or policymaking to be preserved. This suggests that, in turn, and ex post, it becomes possible to test whether evidence supporting certain findings and/or policy decisions still hold. Moreover, unlike traditional databases, blockchain technology makes it possible that immutable records can be stored. This means that the artifacts can be used for further exploitation or repetition of results. In practical terms, the use of blockchain technology creates the opportunity to enhance the evidence-based approach to policy design and policy recommendations that the OECD fosters. That is, it might enable the stakeholders not only to use the data available in the OECD repositories but also to assess corrections to a given policy strategy or modify its scope.

Blockchains and related technologies are still maturing, and several questions related to their use and potential remain underexplored. Several issues require particular consideration in future research, including anonymity, scalability and stability of the data repository. This research took as example OECD data repositories, precisely to make the point that more research and more dialogue between the research and policymaking community is needed to embrace the challenges and opportunities blockchain technology generates. Several questions that this research prompts have not been addressed. For instance, the question of how the sharing economy concept for the specifics of the case could be employed in the context of blockchain has not been dealt with.

The practical implications of the research presented here can be summarized in two ways. On the one hand, by suggesting how a combination of decentralized file systems and an open blockchain, such as Ethereum supporting smart contracts, can ascertain that artifacts are shared, this paper paves the way toward a discussion on how to make this approach and solution reality. The approach and architecture proposed in this paper would provide a way to increase the scope of the reuse of statistical data and results and thus would improve the effectiveness of decision making as well as the transparency of the evidence supporting policy.

Decentralizing analytic artifacts will add to existing open data practices an additional layer of benefits for different actors, including but not limited to policymakers, journalists, analysts and/or researchers without the need to establish centrally managed institutions. Moreover, due to the degree of decentralization and absence of a single-entry point, the vulnerability of data repositories to cyberthreats might be reduced. Simultaneously, by ensuring that artifacts derived from data based in those distributed depositories are made immutable therein, full reproducibility of conclusions concerning the data is possible. In the field of data-driven policymaking processes, it might allow policymakers to devise more accurate ways of addressing pressing issues and challenges.

This paper offers the first blueprint of a form of sharing that complements open data practices with the decentralized approach of blockchain and decentralized file systems. The case of OECD data repositories is used to highlight that while data storing is important, the real added value of blockchain technology rests in the possible change on how we use the data and data sets in the repositories. It would eventually enable a more transparent and actionable approach to linking policy up with the supporting evidence. From a different angle, throughout the paper the case is made that rather than simply data, artifacts from conducted analyses should be made persistent in a blockchain. What is at stake is the full reproducibility of conclusions based on a given set of data, coupled with the possibility of ex post testing the validity of the assumptions and evidence underlying those conclusions.

A blockchain is a shared distributed ledger technology that stores the information of every transaction in the network. The blockchain has emerged with a huge diversity of applications not only in the economic but in the non-economical domain as well. Blockchain technology promises to provide a wide range of solutions to the problems faced during implementation of smart cities. It has the potential to build smart contracts more secure, thus eliminating the need for centralized authority.

This paper presents a proof-of-concept for a use case that uses an Ethereum platform to build a blockchain network to buy, sell or rent a property.

The findings of this study provide an opportunity to create novel decentralized scalable solutions to develop smart cities by enabling paperless transactions. There are enormous opportunities in this distributed ledger technology which will bring a revolutionary change in upcoming years.

The concept of blockchain along with smart contracts can be used as a promising technology for sharing services which is a common requirement in smart cities. All the blockchain transactions are stored in decentralized shared database. The transaction recorded in decentralized system is immutable, it cannot be altered and hence chance of forgery is negligible.