Flexible Multimodal Sub-Gigahertz Communication for Heterogeneous Internet of Things Applications

To realize low-power and low-cost wireless communication over long distances, several wireless standards using sub-1 GHz frequencies have recently been proposed, each with their own strengths and weaknesses in terms of coverage, energy consumption, and throughput. However, none of them are currently flexible enough to satisfy the requirements of future dynamic and heterogeneous IoT applications. To alleviate this, a novel architecture that uses a multimodal device for flexibly employing a variety of heterogeneous sub-1 GHz wireless networks is proposed. It greatly increases network flexibility, resilience, and performance. A device design is presented together with an abstraction layer that combines the different networks into a single flexible virtual network substrate. The article elaborates on the qualitative advantages of this approach. Measurement-based simulation results show advantages in terms of energy efficiency, with significant reduction in energy use compared to a single-technology solution in a representative IoT track and trace scenario. Finally, the article identifies several open research challenges that need to be resolved to fully realize this vision of flexible multimodal communication for demanding IoT applications

Efficient vertical handover in heterogeneous low-power wide-area networks

As the Internet of Things (IoT) continues to expand, the need to combine communication technologies to cope with the limitations of one another and to support more diverse requirements will proceed to increase. Consequently, we started to see IoT devices being equipped with multiple radio technologies to connect to different networks over time. However, the detection of the available radio technologies in an energy-efficient way for devices with limited battery capacity and processing power has not yet been investigated. As this is not a straightforward task, a novel approach in such heterogeneous networks is required. This article analyzes different low-power wide-area network technologies and how they can be integrated in such a heterogeneous system. Our contributions are threefold. First, an optimal protocol stack for a constrained device with access to multiple communication technologies is put forward to hide the underlying complexity for the application layer. Next, the architecture to hide the complexity of a heterogeneous network is presented. Finally, it is demonstrated how devices with limited processing power and battery capacity can have access to higher bandwidth networks combined with longer range networks and on top are able to save energy compared to their homogeneous counterparts, by measuring the impact of the novel vertical handover algorithm

Using SCHC for an optimized protocol stack in multimodal LPWAN solutions

Low Power Wide Area Networks (LPWANs) are formed out of cheap, small, interconnected devices which operate in the sub-GHz domain. The last couple of years, many communication technologies arose in this domain, each with its own characteristics. In order to satisfy more diverse requirements, devices are now equipped with multiple LPWAN radio technologies, which requires the use of a unified protocol stack independent of the underlying LPWAN technology. With its 2128 addresses available and its ability to operate over different link layer technologies, the IPv6 protocol stack would be the ideal candidate. However, many LPWAN configurations do not allow standardized IP/UDP communication, sometimes acquiring more header overhead than there is room for the actual payload. Recently, a new initiative to directly connect constrained devices over IP was initiated by the LPWAN working group of the Internet Engineering Task Force (IETF). This work resulted in the Static Context Header Compression or SCHC mechanism. This header compression mechanism is able to compress the overhead of these internet protocols up to 95%. In order to comply with the IPv6 Maximum Transfer Unit (MTU) of 1280 bytes, a fragmentation mechanism is also included. In this work, we validate the benefits of using SCHC for multimodal LPWAN solutions and show its implementation feasibility on such constrained devices

Joint Technology and Route Selection in Multi-RAT Wireless Sensor Networks with RODENT

International audienceWireless Sensor Networks (WSN) are limited by the characteristics of the Radio Access Technologies (RAT) their are based on. We call a wireless multi-hop network composed of nodes able to use several RAT a Multiple Technologies Network (MTN). Nodes must manage the RAT and route selection, in a local and distributed way, with an suitable communication protocol stack. Nodes may share multiple common RAT with multiple neighbors. Thus the devices' heterogeneity of technologies has to be taken into account by each of the stack's layer. In this article, we introduce our custom Routing Over Different Existing Network Technologies protocol (RODENT), designed for MTN. It is capable of dynamically (re)selecting the best RAT and route based on data requirements evolving over time. RODENT is based on a multi-criteria route selection via a custom lightweight TOPSIS method from our previous work [1]. For an evaluation of performance, we implemented a functional prototype of RODENT on Pycom FiPy devices. Results show that RODENT enables multiple data requirements support and energy savings, while increasing effective coverage

Secure services integration and edge computing for effective beekeeping

Many of the issues that require resolution are not easy to mitigate just from the technology perspective. The ancestral learned logic of processes, the people traditions, and many other variants define inner contexts that make the adhesion and efficient use of information technologies a delicate process. The enormous geographical dispersion of the beekeeping economic activity, the mostly amateur profile of beekeepers, and the specificity in the traditional way as the activity is managed, compromises the applicability of integrative measures based on ICTE. Efficient and integrated management of a no-professionalized economic activity depends on two basic principles: i) the existence of effective tools capable of managing that activity and its synergies with other related activities, and ii) an infrastructure (technological, procedural, legal) that supports services properly profiled for any actor in that activity. This paper describes the work-in-process sBee - Smart Beekeeping, an applied research project that sought to integrate emerging technologies on the innovative management of critical issues that beekeeping needs to overcome. Electronic devices, Internet-of-things, advanced management algorithms, and innovative visualization services were explored. The global system architecture, its supporting services, and the communication infrastructure are here described. The integration of both internet-of-things and communications services, with the common beekeeping?s management tasks, levered a proposal for improving this activity to become more effective. Furthermore, an advanced technological supporting platform was created and experimented, prepared for further developments, on mitigating emergent challenges that the digitization promotes, namely the security and traceability on food and related agriculture value-chains, as well as on the predictive and intelligent perception of current and future scenarios.911A-2C18-106F | Carlos Jorge Enes Capit?o de AbreuN/

An end-to-end LwM2M-based communication architecture for multimodal NB-IoT/BLE devices

The wireless Internet of Things (IoT) landscape is quite diverse. For instance, Low-Power Wide-Area Network (LPWAN) technologies offer low data rate communication over long distance, whereas Wireless Personal Area Network (WPAN) technologies can reach higher data rates, but with a reduced range. For simple IoT applications, communication requirements can be fulfilled by a single technology. However, the requirements of more demanding IoT use cases can vary over time and with the type of data being exchanged. This is pushing the design towards multimodal approaches, where different wireless IoT technologies are combined and the most appropriate one is used as per the need. This paper considers the combination of Narrow Band IoT (NB-IoT) and Bluetooth Low Energy (BLE) as communication options for an IoT device that is running a Lightweight Machine to Machine/Constrained Application Protocol (LwM2M/CoAP) protocol stack. It analyses the challenges incurred by different protocol stack options, such as different transfer modes (IP versus non-IP), the use of Static Context Header Compression (SCHC) techniques, and Datagram Transport Layer Security (DTLS) security modes, and discusses the impact of handover between both communication technologies. A suitable end-to-end architecture for the targeted multimodal communication is presented. Using a prototype implementation of this architecture, an in-depth assessment of handover and its resulting latency is performed

RODENT: a flexible TOPSIS based routing protocol for multi-technology devices in wireless sensor networks

International audienceWireless Sensor Networks (WSN) are efficient tools for many use cases, such as environmental monitoring. However WSN deployment is sometimes limited by the characteristics of the Radio Access Technologies (RATs) they use. To overcome some of these limitations, we propose to leverage the use of a Multiple Technologies Network (MTN). What we refer to as MTN is a network composed of nodes which are able to use several RAT and communicating wirelessly through multi-hop paths. The management of the RAT and routes must be handled by the nodes themselves, in a local and distributed way, with a suitable communication protocol stack. Nodes may reach multiple neighbors over multiple RAT. Therefore, each stack's layer has to take the technologies' heterogeneity of the devices into account. In this article, we introduce our custom Routing Over Different Existing Network Technologies protocol (RODENT), designed for MTN. It enables dynamic (re)selection of the best route and RAT based on the data type and requirements that may evolve over time, potentially mixing each technology over a single path. RODENT relies on a multi-criteria route selection performed with a custom lightweight TOPSIS method. To assess RODENT's performances, we implemented a functional prototype on real WSN hardware, Pycom FiPy devices. Unlike related prototypes, ours has the advantage not to rely on specific infrastructure on the operator's side. Results show that RODENT enables energy savings, an increased coverage as well as multiple data requirements support

Design and evaluation of a scalable Internet of Things backend for smart ports

Internet of Things (IoT) technologies, when adequately integrated, cater for logistics optimisation and operations' environmental impact monitoring, both key aspects for today's EU ports management. This article presents Obelisk, a scalable and multi-tenant cloud-based IoT integration platform used in the EU H2020 PortForward project. The landscape of IoT protocols being particularly fragmented, the first role of Obelisk is to provide uniform access to data originating from a myriad of devices and protocols. Interoperability is achieved through adapters that provide flexibility and evolvability in protocol and format mapping. Additionally, due to ports operating in a hub model with various interacting actors, a second role of Obelisk is to secure access to data. This is achieved through encryption and isolation for data transport and processing, respectively, while user access control is ensured through authentication and authorisation standards. Finally, as ports IoTisation will further evolve, a third need for Obelisk is to scale with the data volumes it must ingest and process. Platform scalability is achieved by means of a reactive micro-services based design. Those three essential characteristics are detailed in this article with a specific focus on how to achieve IoT data platform scalability. By means of an air quality monitoring use-case deployed in the city of Antwerp, the scalability of the platform is evaluated. The evaluation shows that the proposed reactive micro-service based design allows for horizontal scaling of the platform as well as for logarithmic time complexity of its service time