Title Participants Abstract "Comparative study of peer-to-peer architectures for scalable resource discovery" "Jeroen Famaey, Jef Donders, Tim Wauters, Frédéric Iterbeke, Niels Sluijs, Bart De Vleeschauwer, Filip De Turck, Piet Demeester, Rudy Stoop" "Resource discovery is an important aspect of many modern large-scale distributed systems. In the past, this problem has been solved using many different approaches, such as a central registry server, flooding-based protocols, and distributed hash tables. In this paper, these three widely used architectures are compared, using measurement results obtained from real implementations run on an Emulab emulation environment. This allows us to study the advantages and disadvantages of the architectures and determine their usefulness. The measurement study lead to several interesting conclusions. First, the centralised architecture incurs the least traffic overhead. However, it balances the load poorly, and introduces a single point-of-failure. Second, of the two decentralised architectures, the distributed hash table generates the least overhead. Finally, hierarchical architectures were shown to be most effective when the fraction of super-peers compared to regular peers is small." "Fostering Energy Transition in Smart Cities: DLTs for Peer-to-Peer Electricity Trading" "Shenja van der Graaf, Akash Madhusudan, Roozbeh Sarenche, Mustafa A. Mustafa" "This paper explores the applications of Distributed Ledger Technologies (DLTs) in Peer-to-Peer (P2P) electricity trading. It highlights the challenges and trade-offs of applying three different DLTs: Blockchain, Directed Acyclic Graph (DAG), and Holochain. First, the study introduces the energy transition concept in the smart city context. Second, P2P electricity trading and its supporting trading mechanisms are introduced. Third, DLTs are defined and three different types of DLTs are introduced. Forth, possibilities, challenges, and consequences of applying DLTs in electricity trading are explained. Last, applying DLTs for P2P electricity trading from different aspects are discussed. This paper provides a benchmark for applying DLTs to foster energy transition in smart cities. It highlights how this type of technology can serve smart circular economy." "An Ecosystem View of Peer-to-Peer Electricity Trading: Scenario Building by Business Model Matrix to Identify New Roles" "Mehdi Montakhabi, Fairouz Zobiri, Shenja van der Graaf, Geert Deconinck, Domenico Orlando, Pieter Ballon, Mustafa A. Mustafa" "This article introduces new roles in future peer-to-peer electricity trading markets. Following a qualitative approach, firstly, the value network of the current electricity market is presented. To do so, service streams, critical roles, activities, and their setting in the electricity market are iden-tified. Secondly, in order to identify the main sources of uncertainty, the business model matrix framework is utilised to analyze peer-to-peer electricity trading. Thirdly, four future scenarios are built based on customer involvement and customer ownership. The outcome of the scenario building is the emergence of new roles, brokers and representatives, in the future peer-to-peer electricity markets. Fourth, based on the four future scenarios, changes in the value network, new roles, and emerging/evolving activities are identified. Finally, the two new roles are discussed from grid structure, security and privacy, legal, and data protection perspectives. The data is gathered by conducting semi-structured interviews with stakeholders in the current electricity market as well as potential disruptors. This article elaborates on the configuration of the value network in the electricity market and highlights the changes that peer-to-peer trading imposes to the status quo. Through the outcomes of the value network analysis, it assists policy makers to consider the requirements and current market players to reconsider their business models." "Using topology information for quality-aware Peer-to-Peer multilayer video streaming" "Niels Sluijs, Tim Wauters, Chris Develder, Filip De Turck, Piet Demeester, Bart Dhoedt" "AmbientTalk: programming responsive mobile peer-to-peer applications with actors" "Tom Van Cutsem, Elisa Gonzalez Boix, Christophe Scholliers, Andoni Lombide Carreton, Dries Harnie, Kevin Pinte, Wolfgang De Meuter" "The rise of mobile computing platforms has given rise to a new class of applications: mobile applications that interact with peer applications running on neighbouring phones. Developing such applications is challenging because of problems inherent to concurrent and distributed programming, and because of problems inherent to mobile networks, such as the fact that wireless network connectivity is often intermittent, and the lack of centralized infrastructure to coordinate the peers. We present AmbientTalk, a distributed programming language designed specifically to develop mobile peer-to-peer applications. AmbientTalk aims to make it easy to develop mobile applications that are resilient to network failures by design. We describe the languages concurrency and distribution model in detail, as it lies at the heart of AmbientTalks support for responsive, resilient application development. The model is based on communicating event loops, itself a descendant of the actor model. We contribute a small-step operational semantics for this model and use it to establish data race and deadlock freedom." "Emerging business models in local energy markets: A systematic review of peer-to-peer, community self-consumption, and transactive energy models (vol 179, 113273, 2023)" "Mustafa Mustafa" "Peer-to-peer counselling and emotional guidance on infertility in Britain and Belgium (1970s–1980s)" "Tinne Claes" "In the wake of sexual and reproductive health counselling in postwar Western Europe, emotional guidance on infertility was as yet neither readily recognised nor available. In this article, we show that in Britain and Belgium, infertile couples themselves identified the need for systematic emotional guidance on their infertility experiences. They set up self-help support groups to provide counselling on infertility in their respective countries. Originally formed by heterosexual, white, middle-class couples, who were childless due to infertility, these support groups were cautious-rather than affirmative-of reproductive technologies to aid conception. In their view, these technologies were not readily available and did not work for everyone. In this social climate, systematic interactions with peers sought to provide emotional guidance to destigmatise infertility and accept childlessness. This emotional guidance was grounded in the contemporary psychological literature-on grief, mourning and other emotions-that the support groups applied to infertility experiences.We suggest that these groups could be seen as among the first-in their respective countries and arguably within Europe-to offer infertility counselling through a peer-to-peer format, which is today recognised as a crucial part of professional infertility counselling provision. In this light, our findings uncover previously unseen connections between grassroots support groups, infertility counselling and emotional guidance in the period before infertility counselling was professionalised in Britain and Belgium. Our analysis is based on various archival and published sources as well as oral history accounts, many of which have not been analysed before. Our findings contribute to the history of sexual and reproductive health, history of self-help, history of counselling, and history of emotions." "On the Anonymity of Peer-To-Peer Network Anonymity Schemes Used by Cryptocurrencies" "Claudia Diaz Martinez" "Emerging business models in local energy markets: A systematic review of peer-to-peer, community self-consumption, and transactive energy models" "Mehdi Montakhabi" "The emergence of peer-to-peer, collective or community self-consumption, and transactive energy concepts gives rise to new configurations of business models for local energy trading among a variety of actors. Much attention has been paid in the academic literature to the transition of the underlying energy system with its macroeconomic market framework. However, fewer contributions focus on the microeconomic aspects of the broad set of involved actors. Even though specific case studies highlight single business models, a comprehensive analysis of emerging business models for the entire set of actors is missing. Following this research gap, this paper conducts a systematic literature review of 135 peer-reviewed journal articles to examine business models of actors operating in local energy markets. From 221 businesses in the reviewed literature, nine macro-actor categories are identified. For each type of market actor, a business model archetype is determined and characterised using the business model canvas. The key elements of each business model archetype are discussed, and areas are highlighted where further research is needed. Finally, this paper outlines the differences of business models for their presence in the three local energy market models. Focusing on the identified customers and partner relationships, this study highlights the key actors per market model and the character of the interactions between market participants." "Billing Models for Peer-to-Peer Electricity Trading Markets with Imperfect Bid-Offer Fulfillment" "Akash Madhusudan, Fairouz Zobiri, Mustafa Mustafa"