2,512 research outputs found
Standardized connectivity and communication for constrained devices
By 2020, an estimated 50 billion devices will be connected to the Internet. This revolution will transform the traditional human-centric internet to an “Internet of Things” (IoT), thereby enabling a whole new range of intelligent services in domains such as manufacturing, health, smart homes, logistics, etc. After introducing the Internet of Things, this talk will discuss the challenges in integrating embedded devices into the Internet, as many of the widely adopted Internet technologies had not been designed for such devices, i.e. devices that have constraints in memory, processing power and energy. We will highlight the latest evolutions in this domain, starting from communication and networking, all the way up to services and semantics. To conclude, we will give a number of examples on how these evolutions have inspired some of our past and ongoing research activities
The EU as a security actor in Africa
Instability and conflict in Africa create a range of security problems for Europe. Rapidly increasing migration via the Mediterranean Sea, extremism and terrorism, as well as cross-border crime, all have implications for security in Europe, but are spill-over effects of instability outside Europe. The European Union has a considerable interest in a stable Africa, and also seems willing to assume a special responsibility for the continent.
This Clingendael report focuses on the European Union’s role as a security actor in Africa. It considers the use of all the policy instruments at the EU’s disposal. The authors concentrate mainly on the question how the integrated approach is evolving, and what consequences this has for the Common Security and Defence Policy
Alternate marking-based network telemetry for industrial WSNs
For continuous, persistent and problem-free operation of Industrial Wireless Sensor Networks (IWSN), it is critical to have visibility and awareness into what is happening on the network at any one time. Especially, for the use cases with strong needs for deterministic and real-time network services with latency and reliability guarantees, it is vital to monitor network devices continuously to guarantee their functioning, detect and isolate relevant problems and verify if all system requirements are being met simultaneously. In this context, this article investigates a light-weight telemetry solution for IWSNs, which enables the collection of accurate and continuous flowbased telemetry information, while adding no overhead on the monitored packets. The proposed monitoring solution adopts the recent Alternate Marking Performance Monitoring (AMPM) concept and mainly targets measuring end-to-end and hopby-hop reliability and delay performance in critical application flows. Besides, the technical capabilities and characteristics of the proposed solution are evaluated via a real-life implementation and practical experiments, validating its suitability for IWSNs
Seamless roaming and guaranteed communication using a synchronized single-hop multi-gateway 802.15.4e TSCH network
Industrial wireless sensor networks (WSNs) are being used to improve the
efficiency, productivity and safety of industrial processes. An open standard
that is commonly used in such cases is IEEE 802.15.4e. Its TSCH mode employs a
time synchronized based MAC scheme together with channel hopping to alleviate
the impact of channel fading. Until now, most of the industrial WSNs have been
designed to only support static nodes and are not able to deal with mobility.
In this paper, we show how a single-hop, multi-gateway IEEE 802.15.4e TSCH
network architecture can tackle the mobility problem. We introduce the Virtual
Grand Master (VGM) concept that moves the synchronization point from separated
Backbone Border Routers (BBRs) towards the backbone network. With time
synchronization of all BBRs, mobile nodes can roam from one BBR to another
without time desynchronization. In addition to time synchronization, we
introduce a mechanism to synchronize the schedules between BBRs to support fast
handover of mobile nodes.Comment: Short paper version of a paper submitted to Ad-Hoc Networks Journal
by Elsevie
A BLE-based multi-gateway network infrastructure with handover support for mobile BLE peripherals
Bluetooth Low Energy (BLE) is a popular technology within the Internet of Things. It allows low-power, star networks to be set up between a BLE gateway and multiple, power-constrained BLE devices. However, these networks tend to be static, not supporting BLE devices that can freely move around in an environment of multiple interconnected BLE gateways and perform handovers whenever necessary. This work proposes two alternative network architectures for mobile BLE peripherals. One leverages on IPv6 over BLE, whereas the other combines default BLE mechanisms with an additional custom controller. On top, we study in detail the handover mechanism that must be present in both architectures and compare the performance of both a passive and active handover approach. The passive handover approach can be set up without any extra implementation, but an active handover approach offers more proactive handover decisions and can provide a much lower handover latency. All proposed solutions have been implemented and validated on real hardware, showing the feasibility of having future infrastructures with support for mobile BLE devices
Impact of EU duty cycle and transmission power limitations for sub-GHz LPWAN SRDs : an overview and future challenges
Long-range sub-GHz technologies such as LoRaWAN, SigFox, IEEE 802.15.4, and DASH7 are increasingly popular for academic research and daily life applications. However, especially in the European Union (EU), the use of their corresponding frequency bands are tightly regulated, since they must confirm to the short-range device (SRD) regulations. Regulations and standards for SRDs exist on various levels, from global to national, but are often a source of confusion. Not only are multiple institutes responsible for drafting legislation and regulations, depending on the type of document can these rules be informational or mandatory. Regulations also vary from region to region; for example, regulations in the United States of America (USA) rely on electrical field strength and harmonic strength, while EU regulations are based on duty cycle and maximum transmission power. A common misconception is the presence of a common 1% duty cycle, while in fact the duty cycle is frequency band-specific and can be loosened under certain circumstances. This paper clarifies the various regulations for the European region, the parties involved in drafting and enforcing regulation, and the impact on recent technologies such as SigFox, LoRaWAN, and DASH7. Furthermore, an overview is given of potential mitigation approaches to cope with the duty cycle constraints, as well as future research directions
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