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Multi-channel cognitive radio ad hoc networks (CRAHNs) and information-centric networking (ICN) will be indispensable for enabling envisioned multimedia-based smart services within the umbrella of smart cities. Cognitive radios enable the efficient and opportunistic use of spectrum bands by using vacant licensed channels, whereas information- centric networking improves content distribution by decoupling producers and consumers. In this work, we discuss the design of information-centric cognitive radio-based networking for multimedia- based applications in smart cities. We examine the potential of the joint design of CRAHNs and ICN, and thoroughly review fundamental aspects and challenges of CR and ICN for smart cities. Subsequently, we qualitatively study the capability of information-centric cognitive radio-based networking for improving network connectivity, content search and distribution, reliability and confined delay in smart city safety and infotainment-based applications. Finally, we highlight future research directions for the design of protocols for this envisioned network that will support smart cities. [ABSTRACT FROM AUTHOR]

Background: Recently, next-generation sequencing techniques have been applied for the detection of RNA secondary structures, which is referred to as high-throughput RNA structural (HTS) analyses, and many different protocols have been used to detect comprehensive RNA structures at single-nucleotide resolution. However, the existing computational analyses heavily depend on the experimental methodology to generate data, which results in difficulties associated with statistically sound comparisons or combining the results obtained using different HTS methods. Results: Here, we introduced a statistical framework, reactIDR, which can be applied to the experimental data obtained using multiple HTS methodologies. Using this approach, nucleotides are classified into three structural categories, loop, stem/background, and unmapped. reactIDR uses the irreproducible discovery rate (IDR) with a hidden Markov model to discriminate between the true and spurious signals obtained in the replicated HTS experiments accurately, and it is able to incorporate an expectation-maximization algorithm and supervised learning for efficient parameter optimization. The results of our analyses of the real-life HTS data showed that reactIDR had the highest accuracy in the classification of ribosomal RNA stem/loop structures when using both individual and integrated HTS datasets, and its results corresponded the best to the three-dimensional structures. Conclusions: We have developed a novel software, reactIDR, for the prediction of stem/loop regions from the HTS analysis datasets. For the rRNA structure analyses, reactIDR was shown to have robust accuracy across different datasets by using the reproducibility criterion, suggesting its potential for increasing the value of existing HTS datasets. reactIDR is publicly available at https://github.com/carushi/reactIDR. [ABSTRACT FROM AUTHOR]

To realize the automatic matching and automatic dispatching of ocean-going cargo in international logistics, a design scheme of automatic matching system for ocean-going cargo in international logistics based on fuzzy scheduling and wireless sensor communication networking technology is proposed. The automatic matching model of ocean-going cargo in international logistics is constructed, and the MVB bus controller is used to schedule the automatic matching of ocean-going cargo in international logistics. Based on PID fuzzy neural network control, the automatic matching dispatching control model of ocean-going cargo in international logistics is constructed. According to the IEC61375 protocol, the wireless sensor communication network design for the automatic matching of ocean-going cargo in international logistics is carried out. According to the results of auto-correlation feature detection, fuzzy scheduling and optimal control of ocean-going cargo auto-matching in international logistics are carried out by extracting the associated features of ocean-going cargo auto-matching in international logistics. In the application layer, the real-time transport protocol is used for automatic scheduling of ocean-going cargo in international logistics. Based on DSP and RAM as the core processors, the hardware development and design of the automatic matching system for ocean-going cargo in international logistics is carried out. The test results show that the automation level of automatic matching device scheduling for ocean-going cargo in international logistics is high, and the throughput performance of scheduling process is better. [ABSTRACT FROM AUTHOR]

Abstract Boosted by trends such as Industrial IoT and Industry 4.0, industrial Ethernet networks (EtherNet/IP, EtherCAT and PROFINET IRT as top-3 players) have been commonly deployed in industrial automation. The aim of this paper is to provide a practical guideline for selecting the right protocol in industrial networked control systems (NCSs) by comparing the performance of these protocols. Communication delays are discussed, formulated and evaluated with a study of a typical NCS. Simulation results demonstrate that with different frame packing, media access scheme, etc., EtherNet/IP, EtherCAT and PROFINET IRT offer different levels of real-time capabilities which lead to different control performance. Highlights • EtherCAT, PROFINET IRT and EtherNet/IP offers various real-time capabilities. • A generic process is established to evaluate communication and control performance. • A guideline to choose the right protocol for a networked control system is provided. [ABSTRACT FROM AUTHOR]

Abstract This paper describes the overlay protocol Chord using the formalism of Abstract State Machines. The formalization concerns Chord actions that maintain ring topology and manipulate distributed keys. We define a minimal set of deterministic constraints and prove that they guarantee the stability of the topological structure of the network and the consistency of data handling. [ABSTRACT FROM AUTHOR]

Abstract Bit commitment is an important tool in the design of many secure cryptographic protocols, such as coin flipping, zero-knowledge proof, and secure computation. In this paper, we present a computationally light-weight bit commitment protocol over a noisy channel. For the security of the proposed protocol, we show that the receiver has almost no information about the committer's secret due to unpredictability of the noises in the communication channel. Hence, the security of our bit commitment protocol does not depend on hard problems; it is information-theoretically secure. Furthermore, the protocol needs only exclusive-or operations. Thus, it is computationally light-weight, and it can be used in the devices whose computing resources are limited. [ABSTRACT FROM AUTHOR]

Underwater wireless sensor networks (UWSNs) will pave the way for a new era of underwater monitoring and actuation applications. The envisioned landscape of UWSN applications will help us learn more about our oceans, as well as about what lies beneath them. They are expected to change the current reality where no more than 5% of the volume of the oceans has been observed by humans. However, to enable large deployments of UWSNs, networking solutions toward efficient and reliable underwater data collection need to be investigated and proposed. In this context, the use of topology control algorithms for a suit-able, autonomous, and on-the-fly organization of the UWSN topology might mitigate the undesired effects of underwater wireless communications and consequently improve the performance of networking services and protocols designed for UWSNs. This article presents and discusses the intrinsic properties, potentials, and current research challenges of topology control in underwater sensor networks. We propose to classify topology control algorithms based on the principal methodology used to change the network topology. They can be categorized in three major groups: power control, wireless interface mode management, and mobility assisted-based techniques. Using the proposed classification, we survey the current state of the art and present an in-depth discussion of topology control solutions designed for UWSNs. [ABSTRACT FROM AUTHOR]

A secret-key agreement for in-band full-duplex (FD) technology can be regarded as a valuable method for establishing security at the physical layer level. In this paper, we study an FD system model in conjunction with a secret-key agreement. The legitimate users interact through two-way channel probing and one-way reconciliation. We first introduce two complementary key generation models for FD and half-duplex (HD) settings, and compare their performances by introducing the key-reconciliation function. Furthermore, we study the impact of probing-reconciliation tradeoff and the role of a strong eavesdropper, and analyze the system performance in the high-signal-to-noise ratio regime. We show that under certain conditions, the FD mode negatively affects the capabilities of the eavesdropper and offers several advantages in terms of secret-key rate over the conventional HD setups. Our analysis reveals that the perfect self-interference cancelation is not necessary to obtain performance gains over the HD mode. [ABSTRACT FROM AUTHOR]

There are many marketing methods used to attract customers' attention and customers search for special discounts and conduct research to get products cheaper. Using discount coupons is one of the widely used methods for obtaining discounts. With the development of technology, classical paper-based discount coupons become e-coupons and then turn into mobile coupons (m-coupons). It is inevitable that retailers will use m-coupon technology to attract customers while mobile devices are used in daily life. As a result, m-coupon technology is a promising technology. One of the significant problems with using m-coupons is security. Here it is necessary to ensure the safety of the seller's and retailer's data and to prevent unnecessary loss of income. In this study, a new m-coupon protocol is proposed and analyzed against well-known attacks: impersonation, man-in-the-middle, eavesdropping, replay, data modification, unauthorized coupon copying/generation, and multiple cash-in attacks. Then, to show that both the client and the retailer's data are at the highest level of security, the protocol is subjected to security analysis with a powerful protocol analysis tool, Scyther. Thus, the proposed protocol is proved to meet all safety criteria. To the best of our knowledge, this protocol is the first m-coupon protocol for which formal security analysis is conducted by the protocol's developers. [ABSTRACT FROM AUTHOR]

With the development of vehicle networks, the information transmission between vehicles is becoming increasingly important. Many applications, particularly regarding security, are based on communication between vehicles. These applications have strict requirements for factors such as the quality of communication between vehicles and the time delay. Many theoretical communication protocols ignore the presence of buildings or other obstacles that are present during practical use, especially in urban areas. These obstacles can cause a signal to fade or even block direct communication. Many vehicles are often parked at the roadside. Because of their location, these parked vehicles can be used as relays to effectively reduce the shadowing effect caused by obstacles and even solve communication problems. In this paper, we study the problem of parked-vehicle-assistant relay routing communication in vehicle ad hoc networks. We propose an efficient parked vehicle assistant relay routing algorithm that is composed of four parts: a periodic Hello packet exchange mechanism, candidate relay list update, communication link quality evaluation, and candidate relay list selection. Simulation results reveal obvious advantages for indexes such as the quality of communication, success rate, and time delay. [ABSTRACT FROM AUTHOR]

The design of an efficient medium access control (MAC) protocol for multichannel ad hoc cognitive radio networks is an important problem and has been the topic of extensive recent research. In this paper, we present the design and performance evaluation of a protocol, group MAC (GMAC), which is customized for a situation that commonly arises in ad hoc networks: The network consists of multiple groups of nodes such that a large fraction of the traffic of each node needs to be sent to other nodes of its own group. Some examples are 1) units (e.g., platoons) in a military ad hoc network; 2) divisions in an emergency or disaster relief network; and 3) departments in a corporate or university network. Our protocol requires each secondary node to have only one narrowband transceiver, does not rely on a control channel, and incorporates a novel technique for dynamically balancing the traffic load of secondary nodes across the set of free channels. We formulate the problem of partitioning the network nodes into groups based on the volumes of data traffic to be sent between different pairs of nodes, which we call the group formation problem (GFP). We show that the GFP is NP-complete and propose a greedy algorithm to solve it. We analyze the stability region of the GMAC protocol using a queuing theoretic framework. Our extensive simulations show that a large fraction of the bandwidth unoccupied by primary users is utilized by the GMAC protocol for data transmissions. [ABSTRACT FROM AUTHOR]

Content caching on the edge of 5G networks is an emerging and critical feature to quench the thirst for content of future connected cars. However, the tight packaging of 5G cells, the finite storage capacity at the edge, and the need for content availability while driving motivate the need to develop smart edge caching strategies adapted to the mobility characteristics of connected cars. In this paper, we propose a scheme called RoadsIde CacHe (RICH), which optimally caches content at edge nodes where connected vehicles require it most. In particular, our scheme is designed to ensure in-order delivery of content chunks to end users. Unlike blind popularity decisions, the probabilistic caching used by RICH accounts for the user mobility information that the system can realistically acquire. Furthermore, we provide a complete system architecture and define the protocols through which the different system entities can interact. We assess the performance of our approach against state-of-the-art solutions, under realistic mobility datasets and system scenarios. Our RICH edge caching scheme improves significantly the content availability at the caches and reduces the required backhaul bandwidth, with beneficial effects for both the end users and the network operators. [ABSTRACT FROM AUTHOR]

The portfolio of models offered by car manufacturing groups often includes many variants (i.e., different car models and their versions). With such diversity in car models, variant management becomes a formidable task. Thus, there is an effort to keep the variants as close as possible. This simple requirement forms a big challenge in the area of communication protocols. When several vehicle variants use the same signal, it is often required to simultaneously schedule such a signal in all vehicle variants. Furthermore, new vehicle variants are designed incrementally in such a way as to maintain backward compatibility with the older vehicles. Backward compatibility of time-triggered schedules reduces expenses relating to testing and fine-tuning of the components that interact with physical environment (e.g., electromagnetic compatibility issues). As this requirement provides for using the same platform, it simplifies signal traceability and diagnostics, across different vehicle variants, besides simplifying the reuse of components and tools. This paper proposes an efficient and robust heuristic algorithm, which creates the schedules for internal communication of new vehicle variants. The algorithm provides for variant management by ensuring compatibility among the new variants, besides preserving backward compatibility with the preceding vehicle variants. The proposed method can save about 20% of the bandwidth with respect to the schedule common to all variants. Based on the results of the proposed algorithm, the impact of maintaining compatibility among new variants and of preserving backward compatibility with the preceding variants on the scheduling procedure is examined and discussed. Thanks to the execution time of the algorithm, which is less than one second, the network parameters like the frame length and cycle duration are explored to find their best choice concerning the schedule feasibility. Finally, the algorithm is tested on benchmark sets. [ABSTRACT FROM AUTHOR]

Recent advances in multi-rotor vehicle control and miniaturization of hardware, sensing, and battery technologies have enabled cheap, practical design of micro air vehicles for civilian and hobby applications. In parallel, several applications are being envisioned that bring together a swarm of multiple networked micro air vehicles to accomplish large tasks in coordination. However, it is still very challenging to deploy multiple micro air vehicles concurrently. To address this challenge, we have developed an open software/hardware platform called the University at Buffalo's Airborne Networking and Communications Testbed (UB-ANC), and an associated emulation framework called the UB-ANC Emulator. In this paper, we present the UB-ANC Emulator, which combines multi-micro air vehicle planning and control with high-fidelity network simulation, enables practitioners to design micro air vehicle swarm applications in software and provides seamless transition to deployment on actual hardware. We demonstrate the UB-ANC Emulator's accuracy against experimental data collected in two mission scenarios: a simple mission with three networked micro air vehicles and a sophisticated coverage path planning mission with a single micro air vehicle. To accurately reflect the performance of a micro air vehicle swarm where communication links are subject to interference and packet losses, and protocols at the data link, network, and transport layers affect network throughput, latency, and reliability, we integrate the opensource discrete-event network simulator ns-3 into the UB-ANC Emulator. We demonstrate through node-to-node and end-to-end measurements how the UB-ANC Emulator can be used to simulate multiple networked micro air vehicles with accurate modeling of mobility, control, wireless channel characteristics, and network protocols defined in ns-3. [ABSTRACT FROM AUTHOR]

Dynamic adaptive streaming over HTTP (DASH) has recently been widely deployed in the Internet and adopted in the industry. It, however, does not impose any adaptation logic for selecting the quality of video segments requested by clients and suffers from lackluster performance with respect to a number of desirable properties: efficiency, stability, and fairness when multiple players compete for a bottleneck link. In this paper, we propose a throughput-friendly DASH rate control scheme for video streaming with multiple clients over DASH to well balance the tradeoffs among efficiency, stability, and fairness. The core idea behind guaranteeing fairness and high efficiency (bandwidth utilization) is to avoid OFF periods during the downloading process for all clients, i.e., the bandwidth is in perfect-subscription or over-subscription with bandwidth utilization approach to 100%. We also propose a dual-threshold buffer model to solve the instability problem caused by the above idea. As a result, by integrating these novel components, we also propose a probability-driven rate adaption logic taking into account several key factors that most influence visual quality, including buffer occupancy, video playback quality, video bit-rate switching frequency and amplitude, to guarantee high-quality video streaming. Our experiments evidently demonstrate the superior performance of the proposed method. [ABSTRACT FROM AUTHOR]

The number of IoT devices has been growing significantly, and mobile network traffic is also increasing explosively. In order to meet the human desire to explore unknown areas, edgeless communications have always been one of the directions for the development of wireless networks. H-STIN is a promising solution to face the problem of large bandwidth requirement, massive machine type communication, and edgeless communication requirements. However, it is difficult to integrate communication protocols, routing problems, and resource allocation in the large-scale and heterogeneous network architecture. Therefore, this article proposes a potential H-STIN architecture based on the development trends of the Internet of Things, mobile networks, and satellite networks. Since TN has adequate computation resource and routing architecture, the backbone network is given to support an entire network, and AS is adopted to achieve regional self-optimization. The SSTIS is composed of the perception layer, the cognition layer, and the intelligence layer. It integrates IoT, SDN, and network functions virtualization technologies to achieve self-monitoring, crisis forecasting, and optimal control. Finally, the promising technical challenge, including integrated route planning and large-scale resource allocation, is given. [ABSTRACT FROM AUTHOR]

Existing CoAP primarily focuses on communication (i.e., client/server-based request/response interaction) between constrained devices in a constrained network. Constrained networks may have large latencies and constrained devices may not be able to respond in a timely manner. Therefore, incorporating delay awareness in the CoAP protocol may prove beneficial for communications between devices. This article presents a new method to support a delay-aware CoAP messaging model, where a Delay- Indicator is proposed to be contained in messages to reflect delay tolerance information. Furthermore, the DelayIndicator can be leveraged by CoAP Clients and CoAP Servers to improve their operations of entering sleep mode to save energy while not violating delay tolerances. With this new enabler, a timeout mechanism for CoAP Responses is put forward to enhance CoAP performance. Simulation results show that incorporating delay awareness in CoAP significantly improves messaging performance. [ABSTRACT FROM AUTHOR]

Multimedia cloud computing has appeared as a very attractive environment for the business world in terms of providing cost-effective services with a minimum of entry costs and infrastructure requirements. There are some architecture proposals in the related literature, but there is no multimedia cloud computing architecture with hybrid features specifically designed for mobile devices. In this article, we propose a new multimedia hybrid cloud computing architecture and protocol. It merges existing private and public clouds and combines IaaS, SaaS and SECaaS cloud computing models in order to find a common platform to deliver real time traffic from heterogeneous multimedia and social networks for mobile users. The developed protocol provides suitable levels of QoS, while providing a secure and trusted cloud environment. [ABSTRACT FROM AUTHOR]

Fuel utilization efficiency and cost reduction are two major goals in designing in-vehicle networks. Aiming to address these two issues, we investigate in-vehicle networking protocols from both wired and wireless perspectives by first presenting representative solutions in each area, then identifying the challenges to current solutions, and finally advocating the use of the automotive Ethernet. Also, we propose a priority-based scheduler for the automotive Ethernet. Our preliminary experiments show that the proposed scheduler is effective and flexible, and thus is applicable to next-generation in-vehicle networks. We hope that further studies in this area can be inspired by our work and will be forthcoming in years to come. [ABSTRACT FROM AUTHOR]

The evolution of Wireless Sensor Networks has led to the development of protocols that must comply with their new restrictions while being efficient in terms of energy consumption and time. We focus on a collision resolution protocol, the so-called Two Cell Sorted (2CS-WSN). We propose three different ways to improve its performance by minimizing the collision resolution time or the energy consumption. After evaluating these proposals and carrying out the comparison with the original protocol, we recommend an improvement to the protocol which reduces the elapsed time by early 8% and the number of retries and conflicts more than 40%. [ABSTRACT FROM AUTHOR]

Recent physical-layer designs capable of decoding multi-packet collisions demonstrate great potential for improving the network performance. Current network protocols, however, tailor the traditional physical layer to avoid collisions and thus cannot fully exploit the benefits of concurrent transmission techniques. In this paper, we propose an innovative generic concurrent transmission aware routing design called mShare. The mShare design exploits the benefits of these techniques by scheduling concurrent senders to utilize co-owned receiver(s) in parallel. This design significantly increases the available number of routing choices and thus improves the network performance. To illustrate the versatility of our design, we test mShare in three settings: unicast, opportunistic routing, and data collection (convergecast). The performance of mShare is evaluated with physical testbed experiments running on USRP and simulations. The experimental results show that compared to conventional designs, mShare: 1) improves 277% of the throughput in unicast; 2) saves 78% of transmissions in opportunistic routing; and 3) reduces 70% of the delivery delay in data collection. [ABSTRACT FROM AUTHOR]

We propose a vehicle-to-roadside communication protocol based on distributed clustering where a coalitional game approach is used to stimulate the vehicles to join a cluster, and a fuzzy logic algorithm is employed to generate stable clusters by considering multiple metrics of vehicle velocity, moving pattern, and signal qualities between vehicles. A reinforcement learning algorithm with game theory based reward allocation is employed to guide each vehicle to select the route that can maximize the whole network performance. The protocol is integrated with a multi-hop data delivery virtualization scheme that works on the top of the transport layer and provides high performance for multi-hop end-to-end data transmissions. We conduct realistic computer simulations to show the performance advantage of the protocol over other approaches. [ABSTRACT FROM AUTHOR]

The coherence protocol presented in this work, denoted MOSAIC, introduces a new approach to face the challenges of complex multilevel cache hierarchies in future many-core systems. The essential aspect of the proposal is to eliminate the condition of inclusiveness through the different levels of the memory hierarchy while maintaining the complexity of the protocol limited. Cost reduction decisions taken to reduce this complexity may introduce artificial inefficiencies in the on-chip cache hierarchy, especially when the number of cores and private cache size is large. Our approach trades area and complexity for on-chip bandwidth, employing an integrated broadcast mechanism in a directory structure. In energy terms, the protocol scales like a conventional directory coherence protocol, but relaxes the shared information inclusiveness. This allows the performance implications of directory size and associativity reduction to be overcome. As it is even simpler than a conventional directory, the results of our evaluation show that the approach is quite insensitive, in terms of performance and energy expenditure, to the size and associativity of the directory. [ABSTRACT FROM AUTHOR]

Network latency and reliability are becoming critical performance indicators for future mission critical services based on wireless connectivity. In this article we present a portable and low-cost measurement framework for quantifying the endto- end (E2E) latency and reliability of communication systems based on single or multiple links. The proposed framework is tailored for characterization of access diversity mechanisms, for example, multi-connectivity or hybrid access methods, which are expected to be essential for ultra-reliable wireless communications in 4G and 5G networks. An active-probe measurement approach is adopted, consisting of a client that transmits timestamped packets to a server, and vice versa, via one or multiple communication links under test. The setup allows us to measure the one-way latency performance in uplink and downlink separately, and allows fully synchronized measurements of multiple links in parallel to understand the benefits of multi-connectivity mechanisms. Traffic generation is flexible in terms of packet size, transport protocol (TCP or UDP), and inter-arrival time interval of the generated packets, hence being a powerful tool for benchmarking the performance for different application-specific message flows. Special emphasis is put on the tail of the latency distribution, that is, the latency that can be achieved with a certain probability constraint, for example, 99.9 percent or beyond. Given the challenge of measuring such rare events, we measure and validate the stability of the measurement equipment to ensure that the observed performance is not compromised by undesired behavior or malfunction of the equipment. The system has a measurement error below 400 μs with 99.9 percent confidence and below 3.1 ms with 99.999 percent confidence. The capability and applicability of the measurement framework is illustrated by a measurement test of two simultaneous LTE connections that provide robust communications to an aerial drone. [ABSTRACT FROM AUTHOR]

Nowadays, Wireless Sensor Networks (WSNs) are pondered as an exploration subject. Currently, progress in electronic communications has directed to multi-purpose Sensor Nodes (SNs) with less price and power consumption. Energy efficiency is a major concern in WSNs as the sensor nodes are battery-operated devices. Clustering based techniques are implemented through data aggregation to make equal energy consumption among SNs for energy efficient data transmission. The existing clustering techniques make use of distinct Harmony Search Algorithm (HSA), Low-Energy Adaptive Clustering Hierarchy (LEACH) and Particle Swarm Optimization (PSO) algorithms. However, these algorithms have exploration exploitation trade-off and local search constraint individually. In order to obtain a global search with faster convergence, Efficient Energy Clustering Protocol (EECP) based on Genetic Algorithm (GA) is recently proposed to detect their immediate neighbors, balance energy consumption load among data transmission routes and energy efficient cluster head selection. The proposed algorithm exhibited high search efficiency and dynamic capability that improves lifetime of SNs. The presentation of the proposed algorithm was assessed using throughput, packet delivery ratio, energy consumption and end to end delay. The proposed algorithm showed an improvement in energy consumption and throughput by 95 and 90 Mbps respectively than existing clustering algorithm. [ABSTRACT FROM AUTHOR]

In real-time systems, the application’s behavior has to be predictable at compile-time to guarantee timing constraints. However, modern streaming applications which exhibit adaptive behavior due to mode switching at run-time, may degrade system predictability due to unknown behavior of the application during mode transitions. Therefore, proper temporal analysis during mode transitions is imperative to preserve system predictability. To this end, in this paper, we initially introduce mode-aware data flow (MADF) which is our new predictable model of computation to efficiently capture the behavior of adaptive streaming applications. Then, as an important part of the operational semantics of MADF, we propose the maximum-overlap offset which is our novel protocol for mode transitions. The main advantage of this transition protocol is that, in contrast to self-timed transition protocols, it avoids timing interference between modes upon mode transitions. As a result, any mode transition can be analyzed independently from the mode transitions that occurred in the past. Based on this transition protocol, we propose a hard real-time analysis as well to guarantee timing constraints by avoiding processor overloading during mode transitions. Therefore, using this protocol, we can derive a lower bound and an upper bound on the earliest starting time of the tasks in the new mode during mode transitions in such a way that hard real-time constraints are respected. [ABSTRACT FROM AUTHOR]

In a distributed computing environment, real-time tasks communicate via a network infrastructure whose stability significantly impacts timing predictability. Network stability includes two aspects. First, the network has to guarantee the deadline requirements of real-time message transmissions in the absence of network failures. Second, the network needs to support dynamic recovery when network failures occur. This paper generalizes previous static routing approaches, which address the first aspect of the network stability, by developing a dynamic failure recovery policy and a protocol to address the second aspect of the network stability. We derive new real-time forwarding paths without compromising the capability of network devices to guarantee deadlines of concurrent real-time transmissions. We implement this mechanism on a network simulation platform and evaluate it on real hardware in a local cluster to demonstrate its feasibility and effectiveness. Experiments confirm the ability to bound recovery delays based on the network parameters. [ABSTRACT FROM AUTHOR]

Abstract The Threshold-based Low-energy Adaptive Clustering Hierarchy (T-LEACH) protocol declares that cluster heads do not have to turn over every round but rather every batch of rounds. In other words, nodes keep serving as cluster heads as long as their energy is higher than a threshold energy. This article imposes upon major drawbacks of T-LEACH protocol and presents a Modified Threshold-based Cluster Head Replacement (MT-CHR) protocol. In the MT-CHR protocol, a new probability of being a cluster head, for any node in any round, has been proposed which agrees fairly with the assumptions introduced in LEACH protocol. Moreover, a new expression for threshold energy is proposed in which delaying the first node death and avoiding any data loss are taken into consideration. The performance of MT-CHR is evaluated using alive nodes, network lifetime, as well as network utilization performance metrics. The results are further compared with those obtained importantly from LEACH and T-LEACH protocols and the contributions of MT-CHR protocol are extremely impressive. As far as the real sensor network is concerned, the MT-CHR protocol is highly applicable and very effective as long-lasting networks are ascertained. [ABSTRACT FROM AUTHOR]

Future Internet is expected to meet explosive traffic growth and extremely complex architecture, which tend to make the traditional NTC strategies inefficient and even ineffective. Inspired by the latest breakthroughs of AI and its power to address large-scale and complex difficulties, the network community has begun to consider shifting the NTC paradigm from legacy rule-based to novel AI-based. As an applied inter-discipline, design and implementation are important. Although there have been some preliminary explorations along this frontier, they are either limited by only envisioning the prospects, or too scattered to provide high-level insight into a general methodology. To this end, we start with the domain knowledge relationships of AI and NTC, summarizing a baseline workflow toward deep reinforcement learning, which will be the dominant method for the AI-NTC paradigm. On top of that, we argue that AI-NTC training and running must be carried out in online environments in closed-loop fashion for the purpose of putting ti into practice. A series of challenges and opportunities are discussed from a realistic viewpoint, and a set of new architecture and mechanism to enable the online and closed-loop AI-NTC paradigm are proposed. Hopefully, this work can help the AI community to better understand NTC and the NTC community to better live with AI. [ABSTRACT FROM AUTHOR]

IoVs have been envisioned to improve road safety and efficiency, and provide Internet access on the move, by providing a myriad of safety and infotainment applications to drivers and passengers. However, with limited spectrum resource, harsh wireless channel, and variable vehicle density, IoV communication faces severe challenges to achieve scalability, efficiency, and reliability. In this article, we propose a context-aware IoV paradigm design to enhance the communication performance, where the high-level contextual information is utilized to bring intelligence in the design. Specifically, through big data analytics on large-scale IoV communication traces collected from an extensive experiment conducted in Shanghai, we investigate the impacts of different contextual information on V2V communication performance. We reveal that among many types of contextual information, the NLoS link condition is a major one that significantly affects V2V link performance. Based on that observation, we discuss three critical but challenging communication paradigm designs with context awareness of V2V link conditions: smart medium resource allocation, efficient routing establishment, and reliable safety message broadcasting. Furthermore, we present a case study of a cooperative beaconing scheme, where machine learning methods are utilized to learn the real-time link contextual information, and vehicles in deep NLoS condition choose helpers to enhance the overall beaconing reliability. [ABSTRACT FROM AUTHOR]

At present, soft real-time data center applications are in a booming development and impose stringent delay requirements on internal data transfers. In this context, many recently proposed data center transport protocols share a common goal of minimizing Flow Completion Time (FCT), and the Shortest Remaining Processing Time (SRPT) scheduling algorithm has attracted widespread attentions for its superior performance in average FCT. However, SRPT suffers from the instability problem, incurring more and more flows left uncompleted even if the traffic load is within the fabric capacity, which implies unnecessary bandwidth waste. To solve the problem, this paper proposes a backlog-aware flow scheduling algorithm (BASRPT) for both giant switch and general topologies. Because of taking into account queue backlogs other than flow sizes at scheduling, we prove that BASRPT is stable and still maintains good FCT performance. To overcome the huge computation overhead and enable distributed implementation, a fast and practical approximation algorithm called fast BASRPT is also developed. Extensive flow-level simulations show that fast BASRPT indeed stabilizes the queue length and obtains a higher throughput while being able to push the FCT arbitrarily close to the optimal value in the condition of feasible traffic loads. [ABSTRACT FROM AUTHOR]

Wireless body area networks (WBANs) can be widely used in wireless medical, motion detection etc. However, the existence of interference results in the increase in energy consumption and delay. To mitigate interference, nodes are prevented from using the same or similar spectrum resources by adopting multi-channel media access control (MAC) protocols. Here, the authors propose a multi-channel MAC protocol towards energy efficiency and low interference (EIMAC). Firstly, the states of each channel are clarified by the channel mapping mechanism. A novel channel selection strategy, considering the unfairness between high or low priorities, then is carried out. After that, considering the characteristics of node including residual energy, user priority, and data volume, the authors propose a low energy consumption enabled transmission mechanism. Lastly, the authors utilise a novel collision avoidance mechanism to reduce the collision probability of packets. Numerical results show that EIMAC significantly enhance the performance of WBANs in terms of delay, throughput, and energy consumption. [ABSTRACT FROM AUTHOR]

Formation control problem for multiagent networks is investigated under the framework of leader-follower consensus. By utilizing the Lyapunov stability theory, two navigational protocols for multiagent network without and with nonlinear dynamics are derived to realize formation control, respectively. In order to achieve the expected formation, controller is adopted to each agent, and the design philosophies of control protocol are required to follow two rules: (i) the destinations of agent are required to be identified and communicating with each other through the network; (ii) at least one agent is needed to be navigator which can detect the difference between its current location and destination. Finally, the two numerical examples are provided to demonstrate the effectiveness of the proposed navigational protocols. [ABSTRACT FROM AUTHOR]

Non-orthogonal multiple access (NOMA) can improve the spectral efficiency by exploiting the power domain and successive interference cancellation, and in order to improve the throughput, it can be applied to random access that plays a crucial role in the Internet of Things to support connectivity for a number of devices with sparse activity. In this paper, we formulate a game when NOMA is applied to ALOHA to decide users’ access or transmission probabilities. We consider a payoff function based on an energy-efficiency metric and drive the mixed strategy Nash equilibrium (NE). Once the NOMA-ALOHA game is successfully formulated, we generalize it to take into account users’ different fading and multiple orthogonal channels, which might be necessary for NOMA-ALOHA to support a number of users in a realistic environment. A distributed algorithm based on gradient play is derived to find the mixed strategy NE (or transmission probabilities) of multichannel NOMA-ALOHA with fading. [ABSTRACT FROM AUTHOR]

1-D gridded design is one of the most promising solutions that can enable the scaling to 10 nm technology node and beyond. Line-end cuts are needed to fabricate 1-D layouts, where two techniques are available to resolve the conflicts between cuts: 1) cut redistribution and 2) cut mask assignment. In this paper, we consider incorporating the two techniques to enable the manufacturing of cut patterns in 1-D gridded design. We consider both 2-mask case (double patterning is performed on the cuts) and 3-mask case (triple patterning is performed on the cuts). We first present an accurate integer linear programming (ILP) formulation that can solve the co-optimization of cut redistribution and mask assignment optimally. In addition, we propose efficient graph-theoretic approaches based on a novel integrated graph model and a longest-path-based refinement algorithm. Experimental results demonstrate that our graph-theoretic approaches are orders of magnitude faster than the ILP-based method and meanwhile it can obtain very comparable results. For 2-mask case, comparing with the method that solves mask assignment and cut redistribution optimally but separately, our graph-theoretic approach that solves the two tasks simultaneously can achieve $95.0{\times }$ smaller cost on average. We also extend our graph-theoretic approach to 3-mask case. Comparing with the method that reduces the 3-mask problem to 2-mask problem and solves it indirectly, our innovative approach that solves the problem directly based on a novel framework of identifying and solving 4-cliques can achieve 7.6% smaller cost on average. [ABSTRACT FROM AUTHOR]

While having high bandwidth-efficiency, the ad-hoc on-demand distance vector (AODV) routing protocol suffers from high signaling overhead due to route request (RREQ) messages flooding, especially when the node density and the number of connections are increased. In order to resolve this broadcast storm problem of the AODV in a high node density mobile ad-hoc network, we propose a geographical on-demand route discovery scheme. Assuming a known location of the destination, the RREQ of the proposed routing protocol is propagated in a unicast manner by employing a novel parsing mechanism for possible duplicate RREQs. The routing overhead of the proposed routing protocol is greatly robust to the node density change. We derive the node density required for the proposed routing protocol to keep the same connectivity as the AODV under the circumstance where the nodes are uniformly distributed. In addition, we present an imaginary destination consideration method to incorporate the uncertainty of the destination’s location due to mobility. Computer simulations show that the proposed scheme enables the RREQ propagation to cover 95% of the one-hop communication area centered at the originally known location of the destination without sacrificing the unicast feature. [ABSTRACT FROM AUTHOR]

We present a unified fault-tolerance framework for task-parallel message-passing applications to mitigate transient errors. First, we propose a fault-tolerant message-logging protocol that only requires the restart of the task that experienced the error and transparently handles any message passing interface calls inside the task. In our experiments we demonstrate that our fault-tolerant solution has a reasonable overhead, with a maximum observed overhead of 4.5%. We also show that fine-grained parallelization is important for hiding the overheads related to the protocol as well as the recovery of tasks. Secondly, we develop a mathematical model to unify task-level checkpointing and our protocol with system-wide checkpointing in order to provide complete failure coverage. We provide closed formulas for the optimal checkpointing interval and the performance score of the unified scheme. Experimental results show that the performance improvement can be as high as 98% with the unified scheme. [ABSTRACT FROM AUTHOR]

We propose a Context-aware Smallworld routing protocol for wireless ad-hoc networks which finds efficient routes to the destination nodes often through a very short chain of intermediate nodes, without using any routing table. This protocol exploits the “small-world” phenomenon of social networks where source-destination pairs typically get connected through few intermediate friends and the individuals can collectively discover such short paths. The key idea behind our routing protocol is that for forwarding an incoming packet to the destination, a node picks the next hop from among the one-hop neighbor from its one-hop neighborhood that is closest to the destination, and multiple randomly selected long-distance neighbor(s), i.e., from outside of its one-hop neighborhood, based on which of these neighbors is closest to the destination. The long-distance neighbors are selected by using their contextual information through a probabilistic mapping. We provide the theoretical foundations behind our protocol. This simple but effective algorithm can meet performance objectives for most scenarios by reducing loss and latency. Simulation results, using synthetic network topologies, have demonstrated that the routing performance of context-aware Smallworld is better than geographical (distance-based) Smallworld and other standard proactive routing protocols (e.g., OLSRv2) when metrics, such as packet losses, end-to-end delays, hop-counts, connectivity drops, and control traffic generated, are used as the key performance indicators. We also show that the proposed protocol is resilient to dynamic topology changes. [ABSTRACT FROM AUTHOR]

Background: In industrial disasters, early detection of problems and crisis management are critical for saving the lives of people and reducing the impact of disasters. Purpose: In this study, we design a special gateway system that bridges the gap between different communication protocols and enables legacy supervisory control and data acquisition systems to function early detection systems for potential industrial disasters. Methods: The system uses a new queue mechanism to substantially improve the problem of data loss found in conventional supervisory control and data acquisition systems and utilizes identification (ID) prioritization to enable early detection of problems. The proposed system is implemented and tested on a Linux-based, 3G-capable Modbus gateway system. Modbus is used as the communication protocol and 3G technology is utilized to provide high-speed wireless data transfer components. The Modbus gateway device uses an ARM-based EP9302 processor and has digital input/output, relay outputs, and RS485 outputs. Conclusion: This study is significant as it is the first work to show the application of the priority query execution method for Modbus gateway devices. [ABSTRACT FROM AUTHOR]

Physically Unclonable Functions (PUFs) represent a promising security primitive due to their unclonability, uniqueness and tamper-evident properties, and have been recently exploited for device identification and authentication, and for secret key generation and storage purposes. In this paper, we present PHEMAP (Physical Hardware-Enabled Mutual Authentication Protocol), that allows to achieve mutual authentication in a one-to-many communication scenario, where multiple devices are connected to a sink node. The protocol exploits the recursive invocation of the PUF embedded on the devices to generate sequences (chains) of values that are used to achieve synchronization among communicating parties. We demonstrate that, under reasonable assumptions, PHEMAP is secure and robust against man-in-the-middle attacks and other common physical attacks. We discuss PHEMAP performance in several operation conditions, by measuring the efficiency of the protocol when varying some of the underlying parameters. Finally, we present an implementation of PHEMAP on devices hosting an FPGA belonging to the Xilinx Zynq-7000 family and embedding an Anderson PUF architecture, and show that the computation and hardware overhead introduced by the protocol makes it feasible for commercial mid-range devices. [ABSTRACT FROM AUTHOR]

In this paper, a novel distributed approach, named GDSOM-P2P, for clustering distributed data resources is proposed by combining, an improved version of Silhouette algorithm, the dynamic Self-Organizing Map (SOM) neural network, and VICINITY protocol as a generic overlay management framework based on self-organization. The proposed GDSOM-P2P is adapted to the dynamic conditions of these networks. In the proposed GDSOM-P2P algorithm, at first, each node extracts a number of important data through the SOM and Silhouette algorithms. Then each of the nodes chooses one of its neighbors with the help of the VICINITY algorithm, and exchanges their important data with their neighbors. By doing this, over a period, the nodes’ data will be distributed over the entire network and the nodes in the network access the summary data model of the whole data. Finally, each node aggregates its internal data with a summary model and then performs the final clustering to cluster its internal data correctly. Evaluation results over a real P2P environment verify the efficiency of proposed GDSOM-P2P. Furthermore, the proposed GDSOM-P2P is also compared with the existing well-established distributed data clustering techniques. The results show a significant accuracy improvement of the proposed method. [ABSTRACT FROM AUTHOR]

We consider a binary hypothesis testing problem in a wireless sensor network, where a fusion center (FC) makes a final decision about the underlying hypothesis. We assume under hypothesis ${\mathcal H}_0$ , sensors’ observations are uncorrelated and identically distributed Gaussian, however, under ${\mathcal H}_1$ they are correlated and nonidentically distributed Gaussian and sensors are unaware of this correlation when making decisions. Sensors send their local binary decisions over power constrained fading channels. We consider both parallel access channel (PAC) and multiple access channel (MAC) models. To obtain the detection statistic in PAC, we assume that the FC utilizes a linear fusion rule, which linearly combines the signals received from all sensors, while in MAC, the signal received at the FC is naturally the coherent sum of the transmitted signals. For both PAC and MAC, we derive modified deflection coefficient (MDC) of the detection statistic at the FC with coherent reception. Choosing MDC as the detection performance metric, we formulate several constrained transmit power optimization problems. In these problems, MDC is the objective function to be maximized and there are three different sets of transmit power constraints: total power constraint, individual and total power constraints, and individual power constraints only. We refer to the solutions of these constrained optimization problems as MDC-based transmit power allocation. When analytical solutions to these constrained optimization problems are elusive, we discuss how these problems can be converted to convex ones. Our results show that, compared with equal power allocation, detection performance improvement provided by our proposed MDC-based power allocation is more significant in MAC. We quantify the improvement in terms of several factors, including the degree of correlation among sensors’ observations, reliability of local decisions (local detection performance indices), communication channel properties, and the type of transmit power constraint. We also study how the power allocation among sensors varies as these factors change. [ABSTRACT FROM AUTHOR]

The design of the media access control (MAC) layer protocol has been considered a key technical issue in ad hoc research in recent years. Considering the demands and feasibility of engineering practice, a new dynamic time-slot allocation (TSA) protocol based on the improved sequential vertex coloring (SVC) algorithm is proposed in this study according to the characteristics of the MAC protocol in ad hoc networks. We analysed the frame structure, interactive process of the protocol, and the dynamic time-slot allocation algorithm. The NS2 software was employed to simulate the performance of the system in three different scenarios. The results demonstrated that parameters such as slot utilisation, throughput, average delay, and fairness were better than those using the IEEE 802.11 and TDMA protocols. [ABSTRACT FROM AUTHOR]

Internet of vehicles (IoV) is a branch of the internet of things (IoT) which is used for communication among vehicles. As vehicular nodes are considered always in motion, hence it causes the frequent changes in the topology. These changes cause major issues in IoV like scalability, dynamic topology changes, and shortest path for routing. Clustering is among one of the solutions for such type of issues. In this paper, the stability of IoV topology in a dynamic environment is focused. The proposed metaheuristic dragonfly-based clustering algorithm CAVDO is used for cluster-based packet route optimization to make stable topology, and mobility aware dynamic transmission range algorithm (MA-DTR) is used with CAVDO for transmission range adaptation on the basis of traffic density. The proposed CAVDO with MA-DTR is compared with the progressive baseline techniques ant colony optimization (ACO) and comprehensive learning particle swarm optimization (CLPSO). Numerous experiments were performed keeping in view the transmission dynamics for stable topology. CAVDO performed better in many cases providing minimum number of clusters according to current channel condition. Considerable important parameters involved in clustering process are: number of un-clustered nodes as a re-clustering criterion, clustering time, re-clustering delay, dynamic transmission range, direction, and speed. According to these parameters, results indicate that CAVDO outperformed ACO-based clustering and CLPSO in various network settings. Additionally, to improve the network availability and to incorporate the functionalities of next-generation network infrastructure, 5G-enabled architecture is also utilized. [ABSTRACT FROM AUTHOR]

An industrial control system combined with IT is not a special thing; however, cyber security in this field does not mature. Therefore, vulnerability analysis techniques for protocols used in this field are clearly needed. In this paper, we propose a novel test case generation technique for a fuzzing test that can be used for various industrial control system protocols. The proposed fuzzing test is designed for generating a cross-field fuzzing test case because of field dependencies, a characteristic of industrial control system protocols. Additionally, we focus on multilayer testing because the weaknesses of lower layer protocols are inherited by upper layer protocols. [ABSTRACT FROM AUTHOR]

Progression of the internet technologies has led to the emergence of internet of things (IoT). One of the familiar deployment of IoT is through radio-frequency identification (RFID) technology. In recent times, RFID based systems are one of the most widely spread applications for tagging and keep tracking purposes in IoT deployment. This is due to their powerful features compared to their counterparts of similar techniques such as barcodes. In contrast, radio-frequency identification systems suffer from various attacks and security threats. The wireless channel used for communication is responsible for the majority of these vulnerabilities. In this paper, we propose a new radio-frequency identification authentication protocol based on elliptic curve cryptography (ECC) to eliminate these vulnerabilities. In addition, we use elliptic curve Diffie-Hellman (ECDH) key agreement protocol to generate a temporary shared key used to encrypt the later transmitted messages. Our protocol achieves a set of security properties likes mutual authentication, anonymity, confidentiality, forward security, location privacy, resistance of man-in-the-middle attack, resistance of replay attack and resistance of impersonation attack. We implement our proposed protocol in real RFID system using Omnikey smartcard reader (Omnikey 5421) and NXP Java smartcards (J3A040). Implementation results shows that our proposed protocol outperform in term of time complexity as compared to other similar protocols and requires less number of operations. [ABSTRACT FROM AUTHOR]

The Internet of Thing (IoT) provides a wide range of services for human convenience by linking the connectivity from different platform devices. The IoT service holds an unlimited potentials, because the knowledge extracted from the big data can be applied to a huge variety service areas such as smart homes, smart buildings and transportations as well. There are lots of IoT service platforms developed by several companies. Except some platforms, most of them have been only focused on the connectivity. As a result, they have some limits for supporting an intelligent service. For the reason, we design the intelligent IoT common service platform architecture and implement the basic operations in this paper. We also develop the IoT Broker for providing the connectivity as well. We hereby verify the usefulness of the proposed service platform by implementing the IoT service on the platform. [ABSTRACT FROM AUTHOR]

The world of connected devices has led to the rise of the Internet of Things paradigm, where applications rely on multiple devices, gathering and sharing data across highly heterogeneous networks. The variety of possible mechanisms, protocols, and hardware has become a hindrance in the development of architectures capable of addressing the most common IoT use cases, while abstracting services from the underlying communication subsystem. Moreover, the world is moving toward new strict requirements in terms of timeliness and low latency in combination with ultra-high availability and reliability. Thus, future IoT architectures will also have to support the requirements of these cyber-physical applications. In this regard, edge computing has been presented as one of the most promising solutions, relying on the cooperation of nodes by moving services directly to end devices and caching information locally. Therefore, in this article, we propose a modular and scalable architecture based on lightweight virtualization. The provided modularity, combined with the orchestration supplied by Docker, simplifies management and enables distributed deployments, creating a highly dynamic system. Moreover, characteristics such as fault tolerance and system availability are achieved by distributing the application logic across different layers, where failures of devices and micro-services can be masked by this natively redundant architecture, with minimal impact on the overall system performance. Experimental results have validated the implementation of the proposed architecture for on-demand services deployment across different architecture layers. [ABSTRACT FROM AUTHOR]

As multimedia services are gaining considerable popularity in the Internet of Things, providing QoE in smart mmIoT becomes a challenging issue. This article conceptualizes a new framework named SMP, to price the QoE rather than the binary data traffic in IoT multimedia services. By introducing PaaR in QoE-driven network scheduling in mmIoTs, a new dimension of price distortion is available in multimedia resource allocation, complementing traditional rate distortion and power distortion resource allocation approaches. This article also discusses open research challenges in SMP resource allocation, including the difficulty of numerical presentation of QoE, the unavailability of packet-level distortion information, and the non-concavity of the utility functions. A case study is presented to illustrate the PaaR potentials of improving QoE through the SMP framework in mmIoTs. [ABSTRACT FROM AUTHOR]

Pervasively implemented IoT systems are introducing unprecedented threats to our society. In this article, aiming to explore the security impact from the emerging and anarchistic IoT systems, we survey the state of the art of the security and privacy issues in the smart IoT world from a networking perspective. We predict that IoT systems will be extensively used by hackers to commit malicious actions given the features of IoT devices and systems. We also discuss the privacy issue caused by IoT systems. Finally, we present our understanding of counterattacks from both the application and theoretical aspects. We hope this article will shed light on the research field for interested readers. [ABSTRACT FROM AUTHOR]