Secure Precise Clock Synchronization for Interconnected Body Area Networks

Secure time synchronization is a paramount service for wireless sensor networks (WSNs) constituted by multiple interconnected body area networks (BANs). We propose a novel approach to securely and efficiently synchronize nodes at BAN level and/or WSN level. Each BAN develops its own notion of time. To this effect, the nodes of a BAN synchronize with their BAN controller node. Moreover, controller nodes of different BANs cooperate to agree on a WSN global and/or to transfer UTC time. To reduce the number of exchanged synchronization messages, we use an environmental-aware time prediction algorithm. The performance analysis in this paper shows that our approach exhibits very advanced security, accuracy, precision, and low-energy trade-off. For comparable precision, our proposal outstands related clock synchronization protocols in energy efficiency and risk of attacks. These results are based on computations

Design and analysis of adaptive hierarchical low-power long-range networks

A new phase of evolution of Machine-to-Machine (M2M) communication has started where vertical Internet of Things (IoT) deployments dedicated to a single application domain gradually change to multi-purpose IoT infrastructures that service different applications across multiple industries. New networking technologies are being deployed operating over sub-GHz frequency bands that enable multi-tenant connectivity over long distances and increase network capacity by enforcing low transmission rates to increase network capacity. Such networking technologies allow cloud-based platforms to be connected with large numbers of IoT devices deployed several kilometres from the edges of the network. Despite the rapid uptake of Long-power Wide-area Networks (LPWANs), it remains unclear how to organize the wireless sensor network in a scaleable and adaptive way. This paper introduces a hierarchical communication scheme that utilizes the new capabilities of Long-Range Wireless Sensor Networking technologies by combining them with broadly used 802.11.4-based low-range low-power technologies. The design of the hierarchical scheme is presented in detail along with the technical details on the implementation in real-world hardware platforms. A platform-agnostic software firmware is produced that is evaluated in real-world large-scale testbeds. The performance of the networking scheme is evaluated through a series of experimental scenarios that generate environments with varying channel quality, failing nodes, and mobile nodes. The performance is evaluated in terms of the overall time required to organize the network and setup a hierarchy, the energy consumption and the overall lifetime of the network, as well as the ability to adapt to channel failures. The experimental analysis indicate that the combination of long-range and short-range networking technologies can lead to scalable solutions that can service concurrently multiple applications

Preface

Originating from the need stressed by several scholars to devote more research to the complex relationship between the local food producers and processors on the one hand and the tourist industry on the other, this book aims to build a bridge between these two realities. Having practised fruitful research cooperation on farm tourism between the Universities of G\uf6ttingen and Bologna for several years, the editors of this book aim to broaden the scope of both the involved universities and the research streams. To this purpose, in December 2009, a conference on \u201cFood, Agri-Culture and Tourism\u201d took place in G\uf6ttingen under the aegis of the DIH (Deutsch-Italienische Hochschulzentrum) and the DAAD (Deutscher Akademischer Austausch Dienst). This book comprises the work presented at this event as well as combining further results and best practice case studies from scholars and practitioners from more than eleven universities. To this purpose, the book has an interdisciplinary approach. Regarding the structure, there are three main sections. The first part is entitled \u201cFarm and rural tourism\u201d and analyzes the tourist sector in many European countries. Stockebrand, Sidali and Spiller compare different communication styles to promote high-quality food in German farm tourism. Regoli, Vittuari and Segr\ue8 focus their analysis on the recent evolution of rural and farm tourism in Romania. Finally, Bianchi offers a diachronical overview of agritourism in the context of the common agricultural policy and comments on the Italian law No. 96/2006 which is entirely dedicated to the promotion of agritourism. As the title already suggests, the second part of the book links the topic of farm and rural tourism with the sector of food and wine. As shown by Canavari et al. farm operators who tailor educational activities for school groups can make an important contribution to improve the nutritional habits of these young farm guests. Dreyer and M\ufcller claim that cooperative marketing can display economic benefits also at a regional level, using the example of the synergies established between tourist operators and wine makers in the region of Saale-Unstrut. Thus, the challenges posed by the rapidly changing behaviour of customers seem to be well managed by farmers who are eager to try new ways to attract guests and appreciate acting together. Creativity is another important driver of success, as it is shown in the best-practice described by Sch\ue4tzel, Arens and Sch\ue4tzel. Buiatti stresses the important role of other intermediaries, such as the Slow Food Association, who mediate between individuals and farmers. The latter in fact often ignore the new sensitivity of customers for a more sustainable and authentic way of food production. Other strategies for helping farmers to better profile their oeno-gastronomical offer as a unique selling proposition are discussed in section three which is entitled \u201cNew avenues of research: online marketing and sensory analysis\u201d. While Gyau and Stringer as well as Fuchs and H\uf6pken show the pros and cons of adopting emarketing strategies in the farm and rural hospitality industry, Santini, Cavicchi and Canavari as well as Scharf focus on the growing importance of sensory analysis for better identification of market-segments based on their sensory attributes. Hence, as stressed by Telfer and Wall in 1996 \u201crelationships between tourism and food production can be placed on a continuum ranging from conflict through coexistence to symbiosis\u201d. This book claims, more than 10 years later, that above all rural and farm tourism has proven to be an example of such a symbiotic relationship between tourism and the food industr

TinyEVM: Off-Chain Smart Contracts on Low-Power IoT Devices

With the rise of the Internet of Things (IoT), billions of devices ranging from simple sensors to smart-phones will participate in billions of micropayments. However, current centralized solutions are unable to handle a massive number of micropayments from untrusted devices.Blockchains are promising technologies suitable for solving some of these challenges.Particularly, permissionless blockchains such as Ethereum and Bitcoin have drawn the attention of the research community.However, the increasingly large-scale deployments of blockchain reveal some of their scalability limitations. Prominent proposals to scale the payment system include off-chain protocols such as payment channels. However, the leading proposals assume powerful nodes with an always-on connection and frequent synchronization. These assumptions require in practice significant communication, memory, and computation capacity, whereas IoT devices face substantial constraints in these areas. Existing approaches also do not capture the logic and process of IoT, where applications need to process locally collected sensor data to allow for full use of IoT micro-payments.In this paper, we present TinyEVM, a novel system to generate and execute off-chain smart contracts based on sensor data.TinyEVM\u27s goal is to enable IoT devices to perform micro-payments and, at the same time, address the device constraints.We investigate the trade-offs of executing smart contracts on low-power IoT devices using TinyEVM.We test our system with 7,000 publicly verified smart contracts, where TinyEVM achieves to deploy 93 % of them without any modification.Finally, we evaluate the execution of off-chain smart contracts in terms of run-time performance, energy, and memory requirements on IoT devices.Notably, we find that low-power devices can deploy a smart contract in 215 ms on average, and they can complete an off-chain payment in 584 ms on average