In addition to blockchain, a new paradigm is gaining momentum in the filed of distributed ledger technology—directed acyclic graphs. This paper compares two paradigms focusing on features relevant systems using following representative implementations: Bitcoin, Ethereum and Nano. We examine applied data structures for maintaining ledger, consensus mechanisms, transaction confirmation confidence, size, scalability.

Mobile crowdsensing (MCS) is a human-driven Internet of Things service empowering citizens to observe the phenomena individual, community, or even societal value by sharing sensor data about their environment while on move. Typical MCS implementations utilize cloud-based centralized architectures, which consume lot computational resources and generate significant network traffic, both in mobile networks toward services. edge computing (MEC) natural choice distribute solutions moving...

The Internet of Things is evolving around a plethora vertical platforms, each specifically suited to given scenario and often adopting proprietary communications, device resource control protocols. emerging need for cross-domain IoT applications services highlights the necessity interoperability across platforms unified secure sharing access sensing/actuating resources. This position paper describes current state landscape, opportunities that appear towards its sustainable evolution as well...

Sensor technology and sensor networks have evolved so rapidly that they are now considered a core driver of the Internet Things (IoT), however data analytics on IoT streams is still in its infancy. This paper introduces an approach to by using OpenIoT <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> middleware; real time event processing clustering algorithms been used for this purpose. The platform has extended support stream thus we...

Supply chain management enhanced by the Internet of Things (IoT) solutions integrate special tags (e.g., RFID, NFC, and QR-codes) with products to create Smart Tags, in addition storing supplemental information about a product, which is also used track during their lifecycle. However, product consumer has implicitly trust Tag creator other stakeholders within supply that they are providing authentic data product's tag. The DL-Tags solution steps into this environment offer decentralized,...

Edge computing is a viable approach to improve service delivery and performance parameters by extending the cloud with resources placed closer given environment. Numerous research papers in literature have already identified key benefits of this architectural approach. However, most results are based on simulations performed closed network environments. This paper aims analyze existing implementations processing environments containing edge resources, taking into account targeted quality...

Even though various commercial Smart City solutions are widely available on the market, we still witnessing their rather limited adoption, where typically bound to specific verticals or remain in pilot stages. In this paper argue that lack of a regulatory framework is one major obstacles for wider adoption services practice. Such should be accompanied by examples good practice which stress necessity adopting interoperable services. Development and deployment can incur significant costs...

The increasing popularity of information services that rely on content delivery in mobile environments motivates the need for a push service - an efficient and flexible dissemination targets users. We analyze features by investigating representative usage scenarios propose architecture systems. is based publish/subscribe (P/S) paradigm which supports many-to-many interaction loosely-coupled entities. define set to collaborate with P/S infrastructure address dynamics environments.

The suitability of peer-to-peer (P2P) approaches for full-text Web retrieval has recently been questioned because the claimed unacceptable bandwidth consumption induced by from very large document collections. In this contribution we formalize a novel indexing/retrieval model that achieves high performance, cost-efficient indexing with highly discriminative keys (HDKs) stored in distributed global index maintained structured P2P network. HDKs correspond to carefully selected terms and term...

We are witnessing the rise of a novel class wearable devices equipped with various sensing capabilities as well further miniaturization components that nowadays being integrated into mobile devices. The inherent mobility such has capacity to produce dense and rich spatiotemporal information about our environment creating Internet Things (IoT). management resources enable sensor discovery seamless integration geotagged data cloud-based IoT platforms creates new challenges due device...

In this paper, we present a query-driven indexing/retrieval strategy for efficient full text retrieval from large document collections distributed within structured P2P network. Our indexing is based on two important properties: (1) the generated index stores posting lists carefully chosen term combinations, and (2) containing too many references are truncated to bounded number of their top-ranked elements. These properties guarantee acceptable storage bandwidth requirements, essentially...

The rapid progress of urbanization is leading to serious air and noise pollution. Therefore, significant research effort focused on creating a fine-grained pollution maps identify urban areas with critical negative impact human health. traditional measuring methods typically use expensive static equipment which not suitable for dynamic environments because the low spatio-temporal density measurements. On other hand, growing popularity mobile phones, their technological capabilities, opens...

The success of the sustainable transformation energy sector, both in terms planning and operation, relies on new entities, business models, technologies. shift from a relatively small number centralized bulk producers single direction flow to decentralized multi-actor renewable system with two-way multi-way information needs be accompanied by technological solutions. Blockchain other Distributed Ledger Technologies (DLT) represent technology for creating opportunities challenges different...

The integration of Internet Things (IoT) technology into agriculture has revolutionized farming practices by using connected devices and sensors to optimize processes facilitate sustainable execution. Because most IoT have limited resources, the vital requirement efficiently manage data traffic while ensuring security in agricultural solutions creates several challenges. Therefore, it is important study amount that protocols generate for resource-constrained devices, as a direct impact on...

In this paper we focus on mobile crowdsensing applications for community sensing where sensors and devices jointly collect share data of interest to observe measure phenomena over a larger geographic area. Such applications, e.g., environmental monitoring or crowdsourced traffic monitoring, involve numerous individuals that the one hand continuously contribute sensed application servers, other consume information phenomenon typically in their close vicinity. Energy-efficient context-aware...

A sliding window top-k ( top-k/w ) query monitors incoming data stream objects within a of size w to identify the k highest-ranked with respect given scoring function over time. Processing such queries is challenging because, even when an object not at time it enters processing system, might become one in future. Thus set potential has be stored memory while its should minimized efficiently cope high streaming rates. Existing approaches typically store and candidate k-skyband two-dimensional...

We demonstrate an urban crowd sensing application for monitoring air quality by use of specially-designed wearable sensors and mobile phones. The is built upon the OpenIoT platform <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sup> with goal to support context-aware energy-efficient acquisition filtering sensor data in environments while ensuring adequate coverage. how devices jointly collect share interest measure quality. In particular,...

While the current highly fragmented Internet of Things (IoT) ecosystem is characterized by an increasing number platforms, their interoperability and collaboration quite challenging to achieve, even more so due numerous standardization initiatives. However, remains essential for future IoT deployments facilitate emergence novel cross-domain applications business opportunities. In this paper we present approach pursued H2020 project symbIoTe which aims at creating a flexible framework...

Publish/subscribe messaging pattern is often used as a communication mechanism in data-oriented applications and becoming wide-spread, especially due to the expansion of Internet Things (IoT) services applications. In addition MQTT, which one commonly publish/subscribe protocols context IoT, there are number other message queuing solutions, either open or proprietary. We have designed CloUd-based PUblish/Subscribe (CUPUS) middleware solution within framework FP7 project OpenIoT <sup...