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Group communication has become increasing important in mobile ad hoc networks (MANET). Current multicast routing protocols in MANET have been shown to incur large overheads due to dynamic network topology. To this end, this paper proposes an overlay multicast scheme in MANET that is more efficient.

The approach is to construct an overlay multicast tree based on the locations of the group nodes. The paper proposes several tree construction algorithms, namely, location‐guided k‐ary (LGK) tree, location‐guided directional (LGD) tree and location‐guided Steiner (LGS) tree. All of them rely on the geometric locations of the nodes as heuristics to construct the tree. The paper also introduces several mechanisms to enhance the proposed algorithms.

The simulation results show that the location‐guided heuristics is very effective in constructing low bandwidth cost overlay multicast trees in MANET. When location information is up‐to‐date, the bandwidth cost of a LGS tree is similar to that of an optimal router‐assisted Steiner multicast tree. When location information is out‐dated, LGD tree has the lowest cost.

This paper demonstrates the effectiveness of location‐guided heuristics in constructing overlay multicast trees in MANET. This study strongly suggests that location‐guided heuristics can be used to design many other algorithms in a mobile network.

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.

The growth and dynamics of International Management Centres between 1982‐1990 as a network of management development providers is described. The exchange characteristics of the IMC network analysed together with a description of its communicative and symbolic overlays.

To date e‐Learning material has usually been accessed and delivered through a central web server. As the number of users, the amount of information, the frequency of accesses and the volume of data increase, together with the introduction of multimedia streaming applications, a decentralized content distribution architecture is necessary. In this paper we propose the adaptation of the well‐known scalable Content Distribution Networks (CDN) schema for media streaming supported e‐Learning using a novel architecture named COMODIN SCDN (COoperative Media On‐Demand on the InterNet ‐ Streaming Content Distribution Network). COMODIN SCDN utilises surrogates as edge content delivery nodes, incorporates a redirection mechanism able to route requesting clients to the closest copy of the content, encompasses distributed content delivery and management mechanisms to improve the speed, reliability, and scalability of user access to prevent flash‐crowds. Preliminary results in testbeds have shown that COMODIN SCDN increases the efficacy of information distribution through intra and inter‐campus area netwoks. This overlay network will provide learners and educators a scalable, balanced and expeditious access to e‐Learning contents.

The key purpose of this paper is to overview the many issues related to the integration of social sensing and pervasive sensing in the support of adaptive context-aware services.

From the analysis of existing proposals and prototypes, the authors found out that the process of integrating social and pervasive sensing can follow a limited number of approaches, which enables the authors to properly frame the proposals existing in the literature (and/or available as prototype infrastructures) according to a simple taxonomy, which is very useful to make the survey much more effective than a simple list of systems and proposals.

The taxonomy shows that, when integrating social sensing with pervasive sensing, it is possible, at one extreme, to exploit social network as a mere source of information and have such information flow towards the infrastructure supporting the execution of pervasive computing services. At the other extreme, it is possible exploiting a social network as an infrastructure for the integration, by having data from pervasive devices flow towards social networks. In between the extremes, different means can consider to have social networks and pervasive infrastructures converge towards each other to enable the integration of social and pervasive sensing.

Besides introducing the main concepts related to social sensing and framing the key approaches that can be undertaken to pursue the integration with traditional pervasive sensing, the authors go further discussing open issues and key research challenges behind their seamless integration.

The decoupling and asynchrony properties of the content‐based publish‐subscribe paradigm makes it very appealing for dynamic wireless networks, like those that often occur in pervasive computing scenarios. Unfortunately, most of the currently available content‐based publish‐subscribe middleware do not fit the requirements of such extreme scenarios, in which the network is subject to very frequent topological reconfigurations due to mobility of nodes. In this paper we propose a protocol for content‐based message dissemination tailored to Mobile Ad Hoc Networks (MANETs) showing frequent topological changes. Message routing occurs without the support of any network‐wide dispatching infrastructure thus eliminating the need of maintaining such infrastructure on top of a physical network continuously changing its topology. The paper reports an extensive simulation study that confirms the suitability of the proposed approach along with a stochastic analysis of the central mechanism adopted by the protocol.

Nation-states, researchers, and organizations realized the pivotal role of social entrepreneurship in economic development in the recent two decades. The body of knowledge in this domain witnessed consistent research growth but it still lacks a critical review to guide future researchers. This chapter contributes to the body of knowledge by presenting the first bibliometric analysis (using software such as HistCite, VOSviewer, and Biblioshiny). The relevant articles were searched in the Web of Science (WOS) database to ensure the inclusion of high-quality research. Among 910 initially retrieved publications 86 most relevant publications were included in the final dataset. The analysis included various bibliometrics and visualization maps such as the publication trends, most influential articles and journals, most productive countries and organizations, co-citation analysis, and thematic clustering of the research. The findings showed an overall consistent growth in research publications during the last 16 years (2005–2020) with Social entrepreneurship and enterprise: international and innovation perspectives' as the most influential article, Entrepreneurship and Regional Development as the most influential journal, and the United States and the United Kingdom as the most productive countries. The keyword co-occurrence analysis exposed five thematic clusters within the selected dataset indicating a relatively less focus on economic development aspects. Thus, future research should explore how social entrepreneurship, while solving social, cultural, environmental, and community issues, contributes to economic development. The research implications and limitations are discussed in the end.

The feasibility and desirability of reverse logistics in market-motivated contexts are examined in China. Interactions between the major barriers, that hinder or prevent the application of reverse logistics in China are analyzed. Management’s key task is to diagnose barriers to the application of reverse logistics that could be crucial to the organization’s future survival. Simultaneity, a value delivery system exists to create value for customers and environments by supplying needed products and services. Value delivery systems are at the heart of every firm and, more than anything else, determine that, whether the firm survives in the marketplace or disappears into bankruptcy or takeover. The processes and model of market-motivated reverse logistics value delivery system are discussed, and the processes content and model are presented. Simultaneity, based on the advantage of the Third Party Reverse Logistics Providers (3PRLs) and Outsourced Service Providers, an integrated evaluation model is built to select 3PRLs by using the integrated decision-making methods. Reflecting the comprehensive information requirement, the Analytic Hierarchy Process and entropy approaches are applied to calculate the objective weights. A new kind of relative similarity degree is established by combining the Euclidean distance with the grey correlation degree. An example demonstrates the model’s efficiency.

The purpose of this paper is to characterise a number of current and future computing environments and summarises their resource discovery requirements. It then seeks to analyse, with respect to the requirements of each environment, several established service discovery protocols and some newer protocols that are still in the research domain. In addition, the key features of a new resource discovery protocol that has been developed to operate with heterogeneous computing environments are described.

A comprehensive literature survey was undertaken, highlighting the shortcomings of existing resource discovery protocols with respect to large pervasive computing environments. Given the identified gaps in existing protocols, an alternative protocol is suggested.

The main findings of this paper relate to the identified shortcomings of existing resource discovery protocols. It was also found that a hybrid resource discovery protocol capable of spanning dynamic, mobile computing environments and more stable ones was able to overcome many of the challenges presented by large‐scale pervasive computing environments.

This paper presents comprehensive literature survey of the state‐of‐the‐art in resource discovery protocols, pointing out some of the problems that are not solved. The paper describes the design of an alternative protocol, and presents an evaluation of it. The pervasive computing research community can draw upon the survey and evaluation to guide the design of future resource discovery protocols for the increasingly dynamic world in which we live.