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This monograph defines distributed intelligence and discusses the relationship of distributed intelligence to data base, justifications for using the technique, and the approach to successful implementation of the technique. The approach is then illustrated by reference to a case study of experience in Birds Eye Foods. The planning process by which computing strategy for the company was decided is described, and the planning conclusions reached to date are given. The current state of development in the company is outlined and the very real savings so far achieved are specified. Finally, the main conclusions of the monograph are brought together. In essence these conclusions are that major savings are achievable using distributed intelligence, and that the implementation of a company data processing plan can be made quicker and simpler by its use. However, careful central control must be maintained so as to avoid fragmentation of machine, language skills, and application taking place.

A novel distributed middleware service platform, called MidGate platform, is presented in this paper. The central contribution is description of the developed MidGate platform and its architecture focusing especially on the adaptation, context‐awareness, and personalization of mobile and pervasive services. The research problem addressed is how to facilitate the development of interoperable applications and services into heterogeneous and distributed service gateway based environments. A requirement analysis of future mobile and pervasive services and key technologies has been carried out to establish a solid base and requirements for the development of the MidGate platform. The key mechanisms supporting adaptation, context‐awareness, and personalization of applications and services are presented. The novel middleware architecture solution of the MidGate platform utilizing these key mechanisms is also described. The MidGate architecture utilizes the emerging Generic Service Elements (GSE) approach, where generic and collectively utilizable services are provided to applications as middleware services that are part of a service platform. The main contribution of this research is the definition of a set of GSEs, the related MidGate platform architecture and its evaluation. The evaluation of the MidGate platform has been carried out in series of laboratory prototypes. The evaluation indicates that the MidGate platform solution is well applicable in various service gateway‐based distributed systems and extends well into resource‐constrained mobile environments.

To utilize the idle computational resources in a network to collectively solve middle to large problems, this paper aims to propose an integrated distributed computing platform, Java distributed code generating and computing (JDGC).

The proposed JDGC is fully decentralized in that every participating host is identical in function. It allows standard, single machine‐oriented Java programs to be transparently executed in a distributed system. The code generator reduces the communication overhead between runtime objects based on a detailed analysis of the communication affinities between them.

The experimental results show that JDGC can efficiently reduce the execution time of applications by utilizing the networked computational resources.

JDGC releases the developers from any special programming considerations for distributed environment, and solves the portability problem of using system‐specific programming methods.

Application Development for the Distributed Enterprise (ADDE) is a methodological set that supports design of distributed business processes and ICT systems. ADDE provides a guide, a repository and supporting software tools, an underlying meta‐model, based on UML, that may be used in developing further software tools, or adapting existing tools to work with the ADDE repository. The main principles that have driven the authors’ approach to distributed system design are presented. These principles are the focus on distribution issues, the separation of organisational and technical issues, the emphasis on the design process as a decision process, the notion of technological services and the method independence of the guidance. Following this, the guidance on the definition and planning of the application development will be introduced. A presentation of the guidance on distributed application design, as well as the concepts of macro and micro decisions follows. Finally, the future work of the ADDE project will be outlined.

In the last a few years a number of highly publicized incidents of Distributed Denial of Service (DDoS) attacks against high‐profile government and commercial websites have made people aware of the importance of providing data and services security to users. A DDoS attack is an availability attack, which is characterized by an explicit attempt from an attacker to prevent legitimate users of a service from using the desired resources. This paper introduces the vulnerability of web applications to DDoS attacks, and presents an active distributed defense system that has a deployment mixture of sub‐systems to protect web applications from DDoS attacks. According to the simulation experiments, this system is effective in that it is able to defend web applications against attacks. It can avoid overall network congestion and provide more resources to legitimate web users.

The event‐driven paradigm is appropriate for context aware, distributed applications, yet basic events may be too low level to be meaningful to users. The authors aim to argue that this bottom‐up approach is insufficient to handle very low‐level sensor data or to express all the queries users might wish to make.

The authors propose an alternative model for querying and subscribing transparently to distributed state in a real‐time, ubiquitous, sensor‐driven environment such as is found in Sentient Computing.

The framework consists of four components: a state‐based, temporal first‐order logic (TFOL) model that represents the concrete state of the world, as perceived by sensors; an expressive TFOL‐based language, the Abstract Event Specification Language (AESL) for creating abstract event definitions, subscriptions and queries; a higherorder service (Abstract Event Detection Service) that accepts a subscription containing an abstract event definition as an argument and in return publishes an interface to a further service, an abstract event detector; and a satisfiability service that applies classical, logical satisfiability in order to check the satisfiability of the AESL definitions against the world model, in a manner similar to a constraint‐satisfaction problem.

The paper develops a model‐based approach, appropriate for distributed, heterogeneous environments.

Distributed computing systems impose new requirements on the security of the operating systems and hardware structures of the computers participating in a distributed data network environment. It is proposed that multiple level (greater than two) security hardware, with associated full support for that hardware at the operating system level, is required to meet the needs of this emerging environment. The normal two layer (supervisor/user) structure may probably be insufficient to enforce and protect security functions consistently and reliably in a distributed environment. Such two‐layer designs are seen as part of earlier single computer/processor system structures while a minimum three/four‐layer security architecture appears necessary to meet the needs of the distributed computing environment. Such multi‐level hardware security architecture requirements are derived from earlier work in the area, particularly the Multics project of the mid‐1960s, as well as the design criteria for the DEC VAX 11/780 and Intel iAPX‐286 processor and its successors, as two later examples of machine structures. The security functions of individual nodes participating in a distributed computing environment, and their associated evaluation level, appear critical to the development of overall security architectures for the protection of distributed computing systems.

The purpose of this paper is to explore the relationship between perceived distributed leadership and job satisfaction among nurses. Leadership is central to improving quality care. Reports following investigations of poor care standards, identified inadequate leadership as a contributory factor and called for a new kind of leadership. One alternative is distributed leadership. Evidence suggests associations between leadership and job satisfaction but, there is a paucity of research examining associations between distributed leadership and job satisfaction: the purpose of this study was to address this gap.

A cross-sectional survey design was used and data collected via questionnaires. Using census sampling, 350 nurses in a hospital in Malta were selected. A response rate of 50% (n = 176) was achieved. Data were analysed using Spearman’s correlation coefficient and multiple regression. Ethical approval was obtained from relevant committees/individuals.

Results indicated a moderate application of perceived distributed leadership and application of all components of distributed leadership could be improved. Nurses were neither satisfied nor dissatisfied with their jobs. Correlation analysis showed a positive relationship between distributed leadership and job satisfaction. Multiple regression showed that commitment and participative decision-making were major predictors of job satisfaction while supervision by managers had a negative effect.

Improving distributed leadership is a priority in the nursing profession.

To the best of the authors’ knowledge, this study is the first to show that distributed leadership has a positive effect on job satisfaction among nurses. Supervision, a constituent of distributed leadership, was associated with reduced job satisfaction, therefore reducing this is paramount.

The World Wide Web has experienced explosive growth as a content delivery mechanism, delivering hypertext files and static media content in a standardised way. However, this content has been unable to interact with other content, making the Web a distribution system rather than a distributed system. This is changing, however, as distributed component architectures are being adapted to work with the Web’s architecture. This paper tracks the development of the Web as a distributed platform, and highlights the potential to employ an often neglected feature of distributed computing: migration. Argues that all content on the Web, be it static images or distributed components, should be free to migrate according to either the policy of the server, or the content itself. The requirements of such a content migration mechanism are described, and an overview of a new migration mechanism, currently being developed by the authors, is presented.

Cross-layer approach in media access control (MAC) layer will address interference and jamming problems. Hybrid distributed MAC can be used for simultaneous voice, data transmissions in wireless sensor network (WSN) and Internet of Things (IoT) applications. Choosing the correct objective function in Nash equilibrium for game theory will address fairness index and resource allocation to the nodes. Game theory optimization for distributed may increase the network performance. The purpose of this study is to survey the various operations that can be carried out using distributive and adaptive MAC protocol. Hill climbing distributed MAC does not need a central coordination system and location-based transmission with neighbor awareness reduces transmission power.

Distributed MAC in wireless networks is used to address the challenges like network lifetime, reduced energy consumption and for improving delay performance. In this paper, a survey is made on various cooperative communications in MAC protocols, optimization techniques used to improve MAC performance in various applications and mathematical approaches involved in game theory optimization for MAC protocol.

Spatial reuse of channel improved by 3%–29%, and multichannel improves throughput by 8% using distributed MAC protocol. Nash equilibrium is found to perform well, which focuses on energy utility in the network by individual players. Fuzzy logic improves channel selection by 17% and secondary users’ involvement by 8%. Cross-layer approach in MAC layer will address interference and jamming problems. Hybrid distributed MAC can be used for simultaneous voice, data transmissions in WSN and IoT applications. Cross-layer and cooperative communication give energy savings of 27% and reduces hop distance by 4.7%. Choosing the correct objective function in Nash equilibrium for game theory will address fairness index and resource allocation to the nodes.

Other optimization techniques can be applied for WSN to analyze the performance.

Game theory optimization for distributed may increase the network performance. Optimal cuckoo search improves throughput by 90% and reduces delay by 91%. Stochastic approaches detect 80% attacks even in 90% malicious nodes.

Channel allocations in centralized or static manner must be based on traffic demands whether dynamic traffic or fluctuated traffic. Usage of multimedia devices also increased which in turn increased the demand for high throughput. Cochannel interference keep on changing or mitigations occur which can be handled by proper resource allocations. Network survival is by efficient usage of valid patis in the network by avoiding transmission failures and time slots’ effective usage.

Literature survey is carried out to find the methods which give better performance.