Abstract— Machine-to-Machinecommunications comprise a
large number of intelligent devices sharing information and making cooperative decisions without any human intervention. To support M2M requirements and applications which are in perpetual evolution, many standards are designed, updated and rendered obsolete. Among these, arises from The European Telecommunications Standards Institute (ETSI) a promising standard for M2M communications. The ETSI M2M provides in particular a standardized framework for interoperable M2M Services. As most of its peer, this standard does not, however, address the issue of dynamic reconfiguration or provide a suitable model for the reasoning required to build self-managed M2M architectures. In our paper, we propose a graph-based approach built on top of the ETSI standard, including rules for reconfiguration management, to enforce self- management properties of M2M communications.
the message. In asynchronous random access, the reduction of multiple access interference compensates the increased number of interfering packets, and in our reference, scenario TFA shows a twofold increase of capacity over PA. These encouraging results show that the Doppler effect experienced with LEO satellite communications actually increases the performance of TFA with UNB signals, and the advantages offered by the UNB technique could thus also profit satellite networks. In future work, it could be interesting to investigate more deeply how UNB signal with frequency drift behaves with high throughput random access scheme and how advanced signal processing technique such as successive interference cancelation can improve the performance. Regarding interference, the second part of the paper investigates the legitimacy of replacing multiuser interference by a white Gaussian noise in BER analysis. A metric measuring the discrepancy of the BER predicted by the GIA and the exact BER is defined to gauge the accuracy of the GIA. By evaluating this metric taking into account the frequency shift and the frequency drift, it appears that multiuser interference can only be considered Gaussian distributed in restricted cases: low SINR, low INR, and large number of interference. It could be interesting in the future to test more scenarios, with different pulse shaping filters, power imbalance, fading, and check when multiuser interference can be considered Gaussian distributed or not. Even though the numerical results of this study are focused on Gaussian approximation, we proposed general exact model that served as a reference for BER comparisons. Furthermore, the methodology employed to assess the accuracy of Gaussian approximation can also be used to study other distributions and, in particular, generalized Gaussian distribution, 𝛼-stable distribution, or distributions with heavier tail.
C HAPTER 1
Machine type communications (or machinetomachinecommunications), for example: re- mote monitoring, smart city management, and e-health, plays an important role in the infor- mation and communications technology (ICT). Fig. 1.1 shows the evolution of machine type communications (MTC); we can see that machine type communications evolves from Radio- frequency identification (RFID) to Internet of Things (IoT), where anything that can benefit from network connection is connected. Moreover, MTC is now evolving towards digital society, where life efficiency, in terms of economy, mobility, environment, living and gover- nance, is obtained based on the intelligent management, integrated ICTs, and active citizen participation. Of course, Operators are pushing for digital society as the mobile market is saturating and just seeking higher data rates will not create new revenue; they are seeking a paradigm shift to create new revenue. As shown in Fig. 1.2 [ 1 ], the number of MTC devices is 8-9 times larger than human population, and among which only 50 million machines are connected, thus there is great potential for MTC. There are two types of techniques to ac- commodate MTC: wired communication and wireless communications. Compared to wired communication technology, wireless communication has some advantages to enable MTC: mobility, ease of deployment, and robustness [ 2 ]. Specifically, Long Term Evolution (LTE) is seen as an promising technique to enable MTC due to its large coverage, low latency, and high spectral and energy-efficiency.
II.5.2.1 Fixed Packets Transmission Period
In this subsection, a decent comparison is performed between SF conﬁguration methods for a ﬁxed packet transmission interval. Each device randomly selects a time for trans- mission and then it periodically uploads a packet each 50s. Static − SF 12 scored the highest PLR percentage. By adopting this conﬁguration, packets transmitted occupy the spectrum for the longest time on air. Therefore, the highest impact on PLR% was reached due to congestion. Packets arrive at constant intervals and cannot be decoded due to gateway saturation. It is noteworthy to mention that no packets were lost due to lack of sensitivity because increasing the spreading factor increases at its turn the range and the probability for successfully decoding a packet. Unlike static − SF 12, devices with static − SF 7 conﬁguration lost more than half of the packets. However this time, the main loss was due to lack of sensitivity for packets that are mainly transmitted by edge nodes and cannot reach the gateway because SF7 oﬀers the shortest range capa- bility between SF conﬁgurations. Following these assumptions, one can now understand why static − SF 9 could be placed as a trade-oﬀ between range and spectrum occupation with the best overall PLR% between the measured static conﬁgurations. As previously mentioned, increasing SF conﬁguration also increases the spectrum time occupation of packets sent, which also increases the interference PLR% because the probability of receiving packets with the same SF conﬁguration at the same time will also increase.
Abstract—As the number of machine type communications increases at an exponential rate, new solutions have to be found in order to deal with the uplink traffic. At the same time, new types of Base Stations (BS) that use a high number of antennas are being designed, and their beamforming capabilities can help to separate signals that have different angles of arrivals. In this paper, we consider a network where a BS serves a high number of nodes that lacks a receive chain, and we analyze the evolution of the outage probability as a function of the number of antennas at the BS. We then study the effect of an angle offset between the main beam and the desired node’s direction in order to provide realistic results in a beam-switching scenario.
MTCDs are subgrouped into two units: high-priority MTCDs and low-priority MTCDs. Under this model, MTCDs send RRC requests along with a counter value which indicates the number of RA attempts they had done before receiving the successful RAR message. By observing the counter value, the eNB estimates the RA congestion level. Depending on the congestion level and available uplink radio resources, the eNB either increases the RA resources, or decreases the access probability of low priority MTCDs, or takes both actions together. Finally, the new parameters of RA resources and access probability are broadcasted to the MTCD. To increase the reliability of M2M communications, some research works have proposed pre-reservation of some resources from the overall bandwidth for M2M communications only. As for example in (Madueño et al., 2014b), the authors proposed resource reservation for M2M application. Then they split theses resources into preallocated and common resources where the preallo- cated resources are used for sending intended short messages, while the common resources are used for excess messages and retransmission due to transmission errors. In their work all M2M communications are treated equally and are assumed to require resources periodically that does not address the real scenario. As for example, mission critical industrial control applications, communication may not report periodically. Therefore the equal treatment of the M2M de- vices may be detrimental. In (Abdalla & Venkatesan, 2013) suggested a different method to meet the requirements of different applications of M2M communications. They suggested an M2M-Aware schedular that dynamically allocates a fraction of the available resources for M2M devices according to the requirements of the applications so that the QoE of human users is not degraded. In their work, they proposed a new QoS class identifers (QCIs) to support end to end QoS for M2M communications. The allocated resource of M2M communication are then distributed among the M2M devices based on the M2M speciﬁc QCI.
The telecommunication industry is energetically supporting the spreading of the M2M technology as it is expected to be one of the most promising revenue- generating service. Nonetheless, from a standardization point of view, the M2M paradigm is still in its infancy . Both ETSI and 3GPP standards do not pro- vide a secure, fault-tolerant and self-managed M2M architecture, which is a sine qua none condition to the healthy and sustained development of the M2M mar- ket [3, 2, 22, 21]. If neither security nor reliability is provided for M2M commu- nications, this newly emerging paradigm will not be widely adopted. As M2M communication do not intrinsically require human intervention, they should be self-managed and fault-tolerant. Besides, as machines are generally low cost and unattended equipments, they are exposed to several attacks . Furthermore, M2M communications are expected to be primary used for monitoring and teleme- try applications such as in Advanced Metering Infrastructure (AMI) of the smart grids . Fadlullah et al. forecasts in  that AMI is the most promising M2M market growth. However M2M communications over AMI must be secure, fault- tolerant and self-managed to reach a healthy and sustained M2M market expansion. Several researcher have already pointed out this problem. Rongxing et al. noted in  that M2M communications reliability and security have not been well in- vestigated. Geng et al. stated in  that securing M2M communication will be of paramount concern. He also indicates that ”zero-touch” manageability is a serious challenge to an M2M network. Zhang et al. listed in  the challenges raised by M2M communications. Among the presented challenges, he stressed on the security and the self-organization issues. Hence, providing a secure, fault-tolerant and self-managed M2M communication is no more an option, it is a crucial neces- sity. For this purpose, we propose to build a secure and autonomic M2M overlay network over the Internet.
5.8. Performance evaluation 102
188.8.131.52 Strategy space set using fuzzy logic
Diﬀerent from the PID controller where the MTD transmit power has been ad- justed through applying a mathematical model, fuzzy logic is proved to deal with uncertainties (multi-path loss, channel fading) and human perception while approximating the mathematical solution. The basic structure of a fuzzy con- troller is displayed in the previous chapter in Fig. 4.2 . Similarly to Section 4.7.1, we adjust eﬃciently the MTD transmit power using the fuzzy logic con- trol. This latter consists of four processes. In a ﬁrst step, measurements of all variables that represent the relevant conditions of the controlled process, called also antecedents (see Eq. 4.13 and Eq. 4.14 ), are taken. In a second step, the measurements are converted into appropriate fuzzy sets as shown in Fig. 4.4 to express measurements uncertainties which is called the fuzziﬁcation process. The third step consists of the fuzzy inference process that uses the fuzziﬁed measure- ments to evaluate control rules which are shown in table 4.1 . The fourth step is the defuzziﬁcation process where the output of this evaluation that is a fuzzy set is converted into a crisp value using the centroid method as the most popular method. Therefore, the fuzzy power controller dynamically adjusts the transmit power of the speciﬁc MTD in order to assure the QoS of H2H users, maximize the eﬃciency of the MTD spectrum usage and save the battery life of MTDs.
The standardized models for IPTV (ITU-T G.1071, 2015; ITU-T P.1201, 2012) and video te- lephony (ITU-T G.1070, 2012) aim to provide general purpose models for as many use cases as possible. They typically use a very small subset of the features that are available among many applications such as packet loss percentage, frame rate and compression rate, and content com- plexity for bitstream models. However, in this chapter, we have built audiovisual perceived quality estimation models using both the typical small subset of features used in standardized models and the correlated data that we have extracted from the datasets. Based on the results, we know that extracting additional correlated data from the dataset helps us to generate more accurate models when suitable machine learning algorithms are deployed. However, this correlated data depends on the audio and video codec used, the container format, the tools used to extract the features as well as any other features derived by additional computations. The type and the amount of correlated data also depend on what features are measurable within the network. For similar research, we recommend following the approach we have taken here rather than pinpointing specific parameters a priori.
Machine Type Communications (MTC) are automated applications which involve machines or devices that communicate through a network without any human intervention. They can be used today in almost everyday life applications from military to civil applications, such as: transportation, health care, smart energy, supply and provisioning, city automation... Those devices are generally spread in a wide area and should communicate through widely deployed networks. A good candidate to play the role of such a network could be cellular mobile networks. In fact, Cellular networks have been already deployed and offer a large coverage. Such a deployment is beneficial for both mobile network Operators (i.e. more revenues) and the application developers (i.e. more opportunities). Furthermore, LTE networks are all-IP networks and offer a good support for MTC. However, cellular networks are not designed for MTC applications. Consequently, such a deployment is challenging and rises new problems. The most important of them is congestion. In fact, in MTC, a huge number of devices are deployed. This leads to contention and congestion in the the different parts and nodes of the network when a lot of devices communicate at the same time. In the present work, we propose a novel Congestion-Aware Admission Control solution, which deals with the congestion in LTE networks. Our solution, which is based on control theory, effectively allows avoiding the core network congestion while saving the wireless scarce resources. We show its effectiveness through network simulations carried on the ns-3 simulator. In fact, the obtained results show that our solution is robust against different traffic patterns and accommodates huge amount of devices as expected in this particular case of MTC applications. It assures a targeted utilization of the resources in the network. Furthermore, it is completely compliant with the actual protocols and standards.
Abstract—Securing the Internet of Things, more precisely, the ETSI MachinetoMachine (M2M) architecture is a difficult task, since there is a need to secure heterogeneous wireless communications (cellular, wireless, wired), devices (sensor or mobile phone) and applications (programming language, framework, database). In this article, we present the state of the art concerning the security ontologies in various domains (Web, MANET, 2G/GSM, 3G/UMTS, 4G/LTE, Wi-Fi, Intrusion Detection System). Since, most of the ex- isting security ontologies are not published online or do not follow semantic web best practices, we have designed the STAC (Security Toolbox: Attack & Countermeasure) ontology-based security knowledge respecting the semantic web guidelines. The STAC ontology, dataset and application have been designed to help software developers or designers to choose security mechanisms fitting their needs to secure Internet of Things (IoT) applications. STAC is published online (http://sensormeasurement.appspot.com/?p=stac).
Les réseaux actuels et la prochaine génération des réseaux sans fil cellulaires (5G) doivent garantir, non seulement, les communications entre les gens (aussi connu sous le nom d’humain à humain - H2H), mais aussi à un déploiement massif de communication de type machine (MTC). MTC, ou encore Machine à Machine (M2M), peut être considérée comme des appareils qui peuvent établir des communications avec d’autres appareils sans aucune intervention humaine. M2M est aussi vue comme la pierre angulaire de la vision des objets connectés (IoT). Elle attire beaucoup d’attention, car elle peut être considérée comme une nouvelle opportunité pour les opérateurs de réseau et service IoT. Il existe aujourd’hui plusieurs types d’applications se basant sur MTC couvrant plusieurs domaines. On peut citer comme examples les applications suivantes: la santé, les systèmes de transport intelligents (ITS), les compteurs intelligents et les réseaux intelligents, et la sécurité publique (PS).
Why, then, did the monarchy go to such lengths to engage science and expertise in support of colonization? Answers are not hard to find. First, colonial commerce was crucial for the French economy in general and govemment finances in particu lar. The economic principles of mercantilism guided Bourbon policy in colonial matters. On the eve of the Revolution, one person in eight in France lived off of colonial commerce, and 60 percent of 632 million livres of French foreign trade involved colonial products, with taxes, tolls, and duties (totaling up to 50 percent) bringing millions into state coffers. 79 Second, the colonies served as treasured pos sessions in contemporary geopolitics, especially vis-à-vis England, and from the 1660s to the French Revolution a driving purpose of the scientifico-technical appara tus of France was to develop the colonies as part of the country's international pres ence. France's loss of much of its first colonial empire after 1763 and defeat in the Seven Years' War embittered many, especially in the Marine Royale, and gave a new impetus for reform and expansion of the Marine, especially by scientifically inclined officers. 80 Needless to say, this movement found vindication in the victory over the
With the help of this project and after evaluating the system statistically, all Medical Centers that use Gauze could save budget and time for nurses and medical staff by using the developed Automatic Gauze Machine.
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artisans n’ont pas fait que réparer les machines mises sur le marché par d’autres entreprises, ils sont aussi – certes plus ponctuellement, soit dans le temps, soit parce qu’il s’agit d’activités de niche – producteurs de machines. Les fabricants des premiers avions ont pour la plupart été des artisans, à l’image des frères Wright à Dayton dans l’Ohio, qui construisaient eux-mêmes dans leur atelier de bicyclettes toutes les pièces de leurs engins « plus lourds que l’air » au tout début du XX e siècle (Olivier, 2017). Actuellement, les artisans de l’informatique ne se cantonnent pas tous à la réparation. Ils proposent d’assembler des machines sur mesure pour répondre aux besoins spécifiques de leurs clients. Autrement dit, l’évolution technique et l’invention de nouvelles machines ont donné naissance à des artisanats de la machine dont l’essor a contrebalancé le recul des métiers plus anciens et assuré la pérennité de l’artisanat sur la longue durée.
Si, comme Ricoeur le dit, «au sens ontologique, on entend par événement historique ce qui s'est effecti vement produit dans le passé»'", l'appareil cinémato graphique n'est alors rien d'autre qu'une machine histo riographique. La caméra est sans aucun doute une ma chine à enregistrer des événements passés et un récit filmique est composé de fragments d'événements passés enregistrés, c'est-à-dire les plans. C'est la raison pour laquelle il est impossible d'appliquer stricto sensu au récit filmique la règle qu'édicte Ricoeur à propos du récit scriptural : «le temps du récit de fiction est libéré des contraintes qui exigent de le reverser au temps de l'univers» 17 . Car, à certains égards, c'est en utili s ant des