No abstract

In an operator's datacenter, optical technologies can be employed to perform network function (NF) chaining for larger aggregated flows in parallel with the conventional packet-based fine-grained traffic steering schemes. When network function virtualization (NFV) is enabled, virtualized NFs (vNF) can be placed when and where needed. In this study, we identify the possibility of minimizing the expensive optical/electronic/optical (O/E/O) conversions for NFV chaining in packet/optical datacenters, which is introduced by the on-demand placement of vNFs. When the vNFs of the same NF chain are properly grouped into fewer pods, traffic flows can avoid unnecessary traversals in the optical domain. We formulate the problem of optimal vNF placement in binary integer programming (BIP), and propose an alternative efficient heuristic algorithm to solve this problem. Evaluation results show that our algorithm can achieve near-optimal O/E/O conversions comparable to BIP. We also demonstrate the effectiveness of our algorithm under various scenarios, with comparison to a simple first-fit algorithm.

This paper addresses the microwave energy harvesting on board of geostationary satellites for health satellite monitoring. To prove the feasibility of such a concept, we investigated the electromagnetic environment existing on antenna panels. Based on established cartographic maps, three designs of rectennas are proposed. Measured DC powers ranging from 0.256 mW to 1.28 mW can be harvested for electric field levels ranging from 91 V/m to 121 V/m and by using very simple and compact designs. The harvesting structures consist of only one Schottky diode per rectenna and present a total surface of 2.4 cm 2. They are suitable for powering the new generation of ultralow power transceivers, thus enabling autonomous wireless power networks for satellite health monitoring.

No abstract

This paper addresses the practical implementation of a wireless sensors network designed to actualize cyber-physical systems that are dedicated to structural health monitoring applications in the construction domain. This network consists of a mesh grid composed of LoRaWAN battery-free wireless sensing nodes that collect physical data and communicating nodes that interface the sensing nodes with the digital world through the Internet. Two prototypes of sensing nodes were manufactured and are powered wirelessly by using a far-field wireless power transmission technique and only one dedicated RF energy source operating in the ISM 868 MHz frequency band. These sensing nodes can simultaneously perform temperature and relative humidity measurements and can transmit the measured data wirelessly over long-range distances by using the LoRa technology and the LoRaWAN protocol. Experimental results for a simplified network confirm that the periodicity of the measurements and data transmission of the sensing nodes can be controlled by the dedicated RF source (embedded in or just controlled by the associated communicating node), by tuning the radiated power density of the RF waves, and without any modification of the software or the hardware implemented in the sensing nodes.

This paper addresses the concept of a wirelessly powered and battery-free wireless sensor for the cyber-physical systems dedicated to the structural health monitoring applications in harsh environments. The proposed material architecture is based on a smart mesh wireless sensor network composed of sensing nodes and communicating nodes. The sensing nodes are used to sense the physical world. They are battery-free and wirelessly powered by a dedicated radiofrequency source via a far-field wireless power transmission system. The data collected by the sensing nodes are sent to the communicating nodes that, between others, interface the physical world with the digital world through the Internet. A prototype of the sensing node-using a LoRaWAN uplink wireless communication and temperature and relative humidity sensor-has been manufactured, and the experiments have been performed to characterize it. The experimental results prove that the periodicity of measurement and communication can be controlled wirelessly by using only the wireless power transmission downlink. In this paper, we highlight the performance of this complete implementation of a wirelessly powered and battery-free wireless sensing node-not yet integrated or miniaturized-designed for implementing complete cyber-physical systems and based on the simultaneous wireless information and power transfer. Finally, an investigation of comparable implementations of the battery-free sensing nodes for the cyber-physical systems is carried out. INDEX TERMS Cyber-physical systems (CPS), Internet of Things (IoT), wireless power transmission (WPT), wireless sensor network (WSN), simultaneous wireless information and power transfer (SWIPT), communicating materials.

Telecom providers struggle with low service flexibility, increasing complexity and related costs. Although "cloud" has been an active field of research, there is currently little integration between the vast networking assets and data centres of telecom providers. UNIFY considers the entire network, from home networks up to data centre, as a "unified production environment" supporting virtualization, programmability and automation and guarantee a high level of agility for network operations and for deploying new, secure and quality services, seamlessly instantiatable across the entire infrastructure. UNIFY focuses on the required enablers and will develop an automated, dynamic service creation platform, leveraging fine-granular service chaining. A service abstraction model and a proper service creation language and a global orchestrator, with novel optimization algorithms, will enable the automatic optimal placement of networking, computing and storage components across the infrastructure. New management technologies based on experience from DCs, called Service Provider DevOps, will be developed and integrated into the orchestration architecture to cope with the dynamicity of services. The applicability of a universal node based on commodity hardware will be evaluated in order to support both network functions and traditional data centre workloads, with an investigation of the need of hardware acceleration.

No abstract