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An emerging threat within blockchain systems is the malicious tactic known as eclipse attacks, wherein attackers aim to deceive and gain control over targeted nodes. Despite the increasing popularity of blockchain technology, effective defence mechanisms against eclipse attacks have been lacking. A novel and dynamic defence model designed explicitly for Proof-of-Work (PoW) consensus blockchain systems is proposed to address this critical issue. The model relies on a node-to-node evaluation mechanism to ensure robust protection. By leveraging mutual evaluations conducted between clients and incorporating the renowned Kademlia algorithm, a ranking value is assigned to each node within the defence model. These rankings empower nodes to prudently select trustworthy peers as neighbours based on a threshold comparison, effectively mitigating the risk posed by malicious nodes. Notably, the proposed approach significantly enhances the security of blockchain systems without necessitating modifications to existing protocols or network structures. The effectiveness of the proposed defence model in countering eclipse attacks is extensively validated through a series of experiments. Furthermore, the approach surpasses previous defence strategies, offering a higher probability of successful defence while maintaining minimal overhead. With its straightforward implementation and operational efficiency, the dynamic defence model is an ideal solution for real-world deployment scenarios. This research presents a compelling and robust defence model against eclipse attacks in PoW blockchain systems, addressing the existing gap in defence mechanisms. Furthermore, this advancement paves the way for the wider adoption of blockchain applications across various domains by providing enhanced security, reliability, and trustworthiness. [ABSTRACT FROM AUTHOR]

In today's world of wireless communication, the prime point of concentration lies on data security. This depends mainly on proper authentication of users who are intended to connect to the network. with modern day technology, the credentials (password), which the legitimate user send to the access points for his/her authorization, can be sniffed and used to enter the system, compromising the system security. WPA2/PSK (Wireless Protected Access/Pre-Shared Key) has a vulnerability which allows an attacker to perform Man-in-the-middle attack by capturing the handshake sent by the legitimate user for authentication. The captured handshake can be used to recover the password using dictionary attack or can be brute forced. To overcome the short comings of the current system, the proposed method uses Frequency Hopping Technique to secure the MIC(Message Integrity Code) before transmitting it. This method reduces the possibility of brute forcing the password, even if the handshake is captured. [ABSTRACT FROM AUTHOR]

Although the area of underwater acoustic networking is getting mature and critical for a wide variety of commercial applications, the lack of secure underwater communication standards presents a major impediment for adopting these networking technologies within NATO operations. The NATO Research Task Group IST-174 "Secure Underwater Communications for Heterogeneous Network-enabled Operations" aims to study and to demonstrate secure underwater communications in a holistic approach. In particular, this group's ambition is to define waveforms, network protocols and architectures that will enable underwater connectivity in a secure and interoperable way. To that effect, this paper presents various security concepts and communication systems currently under development that could be included in those standardisation efforts. [ABSTRACT FROM AUTHOR]

The purpose of this research is to investigate the use of a communication network utilizing Long Range (LoRa) low-power wide-area network protocol for the telemetry of detected target chemicals. The sensor platform under development allows traditional electrochemical techniques to be executed with a low Size, Weight, and Power (low SWaP) system that is deployable using an autonomous or remote-controlled vehicle. Once in the field, the sensors communicate target chemical concentrations to a centralized gateway through LoRa to an Internet of Things (IoT) network. Researchers are currently deploying the prototype network for field testing of each node's sensing, meshing, and communication capabilities throughout all weather climates. Developing a robust and dynamic sensor network to monitor the environment and provide a live data feed to detect chemicals of interest in the environment eliminates the need for direct human interaction. The low power consumption of LoRa allows the network nodes to be deployed for an extended amount of time on a single battery supply. [ABSTRACT FROM AUTHOR]

Geocast routing aims the transmission of a message to a community of vehicles in the same geographical area. The GPS information of vehicles, especially taxis, in a city gives reliable information about the traffic pattern of a city. With the help of this information smart models can be created to use when making routing decisions. In this paper, a smart geocasting protocol, GeoAKOM, is introduced and implemented by using the GPS data of taxis in Bursa city, Turkey. In GeoAKOM, the mobility pattern of city is analized in two levels as in GeoMobCon introduced earlier. In the macroscopic level analysis, the city is segmented into clusters using k-means clustering and optimal paths for a message is generated using these clusters. In the microscopic level, mobility based likelihood value is used to make routing decision. The message is transmitted if the encountered vehicle has a larger mobility based likelihood or contact history based likelihood value than the carrying vehicle as in GeoMobCon. Moreover, in GeoAKOM, the next cluster of a vehicle is predicted with the help of all k-order Markov model (AKOM) by using GPS records of all vehicles. Mobility based likelihood calculations are performed by using this prediction. With these features, GeoAKOM provides a robust solution for the vehicles which do not have large GPS record history and which are relatively new in the system. Simulations on real world taxi GPS data are compared for various number of clusters in terms of delivery ratio, average delay, and hop count by using the ONE simulator. Simulation results show that, GeoAKOM provides promising results when compared with GeoMobCon and the First Contact routing algorithms. [ABSTRACT FROM AUTHOR]

In view of the security threats posed inside and outside the network due to the weaknesses of network protocols and systems, power line and wireless converged communications have security problems in communication connections that appear in environments where heterogeneous networks overlap. In order to cope with the problems of network delay and data transmission security in smart grid, this paper proposes an online monitoring security protection method based on edge nodes, which manages user trust under the premise of not leaking grid user data, and establishes a personalized machine learning model. This method not only guarantees users a secure communication experience, but also ensures users' real-time network connection and content acquisition, and can obtain a fast and personalized user experience. [ABSTRACT FROM AUTHOR]

As the use of Wireless Sensor Networks grows, many challenging issues with these networks arise. The utilization of power consumption is one of the most significant issue due to the limited energy constraints of the individual sensor nodes. This limitation imposes a challenge to design the best energy-efficient routing mechanism. This work presented an Energy-Efficient Gossiping protocol (EEGossip) that routes data to the sink by choosing the optimal next node. EEGossip uses Chebyshev distance, residual energy and the sink distance as factors when determining the optimal next node. The result of the proposed work has shown that the proposed protocol improves the total energy consumption of the network and leverages the network lifetime since it decreases the computational overhead and ensures that the best next node is chosen. [ABSTRACT FROM AUTHOR]

Wireless sensor networks is made up of many tiny nodes that has the ability to measure physical phenomena and send the collected measurements to the sink node using multiple-hop protocol with short range transmission. One of the main factors that can be considered to increase the sensor network life is routing protocol. The main goal of routing protocol is to select the most optimal path and make decision of sending the gathering data to the sink node. Inefficient routing protocol leads to more re-transmission of data which consume more energy.Thus, a careful and comprehensive performance analysis of the routing protocols used in any wireless sensor network is required. The main goal of this paper is to study the performance of the RPL protocol under three different MAC protocols named; ContikiMac, CXMAC, NullRDC in terms of end-to-end delay, packet delivery ratio and power consumption to find the best behaviour of the RPL routing protocol under the MAC protocols effect. The results show that NullRDC is better in terms of latency while the ContikiMac outperforms the others in terms of power consumption. [ABSTRACT FROM AUTHOR]

Application of health-care networks is becoming more and more attractive. Electronic-monitoring and movable cameras are the key parts of health - care information collection by mobile electronic devices. Healthy public domain is developed by intellectual approaches. A wide variety of data from electronic-monitoring and movable camera will be stored and shared with continued demand for health-care service demands (e.g., ECG service, personal pulse service information). However, health-care networks and devices usually share the same frequency spectrum that results in inflexible access sharing. Frequency spectrum access sharing makes the challenge of how best to use electronic health-care information and commutation protocol. We design an priority considerations health-care networks and commutation protocol to enhance quality of access sharing and the users' health-care accuracy by stochastic sharing and protocol optimization. The numerical results show that the health-care networks and protocol can enhance capacity of access sharing for users and spectrum utility of networks. [ABSTRACT FROM AUTHOR]

As the use of Wireless Sensor Networks grows, many challenging issues with these networks arise. The utilization of power consumption is one of the most significant issue due to the limited energy constraints of the individual sensor nodes. This limitation imposes a challenge to design the best energy-efficient routing mechanism. This work presented an Energy-Efficient Gossiping protocol (EEGossip) that routes data to the sink by choosing the optimal next node. EEGossip uses Chebyshev distance, residual energy and the sink distance as factors when determining the optimal next node. The result of the proposed work has shown that the proposed protocol improves the total energy consumption of the network and leverages the network lifetime since it decreases the computational overhead and ensures that the best next node is chosen. [ABSTRACT FROM AUTHOR]

Wireless sensor networks is made up of many tiny nodes that has the ability to measure physical phenomena and send the collected measurements to the sink node using multiple-hop protocol with short range transmission. One of the main factors that can be considered to increase the sensor network life is routing protocol. The main goal of routing protocol is to select the most optimal path and make decision of sending the gathering data to the sink node. Inefficient routing protocol leads to more re-transmission of data which consume more energy.Thus, a careful and comprehensive performance analysis of the routing protocols used in any wireless sensor network is required. The main goal of this paper is to study the performance of the RPL protocol under three different MAC protocols named; ContikiMac, CXMAC, NullRDC in terms of end-to-end delay, packet delivery ratio and power consumption to find the best behaviour of the RPL routing protocol under the MAC protocols effect. The results show that NullRDC is better in terms of latency while the ContikiMac outperforms the others in terms of power consumption. [ABSTRACT FROM AUTHOR]

Abstract Intelligent Transportation Systems use Vehicular Ad-hoc Networks to improve road safety. Dedicated Short Range Communications (DSRC or IEEE 802.11p) and Wireless Access in Vehicular Environments (WAVE or IEEE 1609 protocol suite) are the two important standards that govern communication in VANETs. However, DSRC based VANETs cannot guarantee to achieve the Quality of Service (QoS) requirements like reliability and latency under high vehicle density scenario due to network congestion. This paper studies the congestion behavior of IEEE802.11p/1609.4 based Medium Access Control by varying vehicle density in urban and highway conditions. Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) is the default medium access mechanism in WAVE MAC. The metrics chosen for evaluating the performance of CSMA/CA are the average end-to-end delay, average throughput, packet delivery ratio, packet loss ratio and the number of packets lost. The simulation is carried out for both urban and highway scenario under varying vehicle density and communication load. The Simulation is performed using Omnet++ and SUMO based veins framework. The simulation results show that under high vehicle density and high communication load, CSMA/CA fails to meet the required QoS. [ABSTRACT FROM AUTHOR]

Abstract Wireless Sensor Networks (WSNs) have emerged as one of the prominent area of research in the recent times. Sensor-MAC (S-MAC) protocol is one of the Medium Access Control(MAC)protocols, which follows the idea of periodic listen and sleep. In other words, node is active till the time it receives the data packets, otherwise it goes in sleep mode by turning its radio off. However, this protocol lacks in energy conservation due to unnecessary listening to the channel in idle mode. In this paper, we have proposed a new analytical model in which energy is reduced on the basis of the activities it performs in the active mode. A comparison is made between all the different possibilities which can occur at a node, when it listens unnecessarily to the medium. Various energy consuming modes of S-MAC protocol such as transmission, reception, sensing and listening are considered. The proposed work results in the minimizing the energy and reducing the delay in time as compared to that of basic S-MAC protocol. [ABSTRACT FROM AUTHOR]

Major modern day computing and communication rely upon the underlying network used for data transportation. A strong and robust network is a prerequisite for communication oriented applications. One kind of communication networks used for data transportation known as Mobile ad hoc Networks (MANET) have been discussed in this paper and work has been done on their capability enhancement. Mobile ad hoc networks have evolved at a fast pace and provide efficient communication solutions when fixed communication infrastructure is not available and are easily deployable. Traditional mobile ad hoc network works on single wireless communication channel which limits their capacity and capability to handle very large or voluminous data. This limitation can be resolved using multiple physical communication channels. Number of protocols and techniques has been invented to incorporate multi-channel communication capabilities in wireless mobile ad hoc networks each with some pros and cons. In this paper a novel multi-channel wireless communication framework has been presented together with associated techniques and mechanisms. The proposed framework and protocols have been rigorously tested, evaluated and compared with existing benchmarked multi-channel ad hoc network protocols to establish the credibility of the framework. [ABSTRACT FROM AUTHOR]

In modern era WSN, data aggregation technique is the challenging area for researchers from long time. Numbers of researchers have proposed neural network (NN) and fuzzy logic based data aggregation methods in Wireless Environment. The main objective of this paper is to analyse the existing work on artificial intelligence (AI) based data aggregation techniques in WSNs. An attempt has been made to identify the strength and weakness of AI based techniques. In addition to this, a modified protocol is designed and developed. And its implementation also compared with other existing approaches ACO and PSO. Proposed approach is better in terms of network lifetime and throughput of the networks. In future an attempt can be made to overcome the existing challenges during data aggregation in WSN using different AI and Meta heuristic based techniques. [ABSTRACT FROM AUTHOR]

Wireless Sensor Networks (WSNs) are harshly challenged by limited energy. It’s essential to use available energy in efficient manner to maintain sustainability in networks. Sensor nodes once after deployment start depleting their energy in various roles; some may on sensing; some may on communication, some may on aggregating etc. After intense survey its proven fact that communication is the biggest reason of energy consumption. To reduce communication energy requirements clustering plays a very important role. Clustering employs that only cluster heads will participate for communicating aggregated information to far located base station. Challenge comes when cluster heads are managing both roles as heads as well as relay nodes. The role of relay node may require that they are aggregating and communicating their own data as well as other data received due to multi hop communication. This paper focuses on how relay nodes can strengthen clustering. Cluster Heads can save their energy and have prolonged life if sensor networks are optioned with separate relay nodes. This paper has proposed modified Mutual Exclusive Distributive Clustering (MEDC) protocol along relay node. Proposed solution will work to chase relay nodes different from cluster heads and will improve network lifetime further. [ABSTRACT FROM AUTHOR]

The Internet of Things (IoT) is common platform provide connectivity between various type of devices are having communication capability. Main objective of IoT is to deploy effective and high-quality smart services which offer different type services. Therefore, IoT need an advanced protocol stack which provides inter-communications between different types of devices have differet service requirements. IoT uses TCP and UDP as transport layer protocols to achieve the quality of service (QoS) required by different IoT devices. The XMPP (Extensible Messaging and Presence Protocol), MQTT (MQ Telemetry Transport) and RESTful HTTP are IoT application protocols which use TCP as a transport layer protocol. The transport layer protocol offers service point addressing, flow control, congestion control and segmentation, reassembling. As a number of different types of device increases over the Internet, network congestion also increases. In current internet scenario, TCP is responsible for congestion control over the Internet. However, current available TCP versions are not enough capable to handle different type of devices to fulfil the need of IoT. Therefore, this paper provides a survey of various congestion control algorithms used at transport layer. This paper includes available congestion control algorithms, their advantages, disadvantages and existing problems with TCP in IoT domains. [ABSTRACT FROM AUTHOR]

Infrastructures create many problems in the security, economic or health sector. The high level of connectivity on Internet of Things (IoT) field is at the center of new networks and requires interoperable solutions that promote redundancy, and that fault tolerance. Many standard protocols currently allow extensive exchanges between different IoT groups. In this paper, we are interested in reconfigurable links management between sets of IoT linked by Message Queue Telemetry Transport (MQTT). This approach is based on the use of multi-agent systems in charge of arranging network topologies. [ABSTRACT FROM AUTHOR]

Over the next few years, the Industrial Wireless Sensor Network (IWSN), which is a major part of the Industrial Object Internet (IIoT), will play a crucial role in transforming the industrial world by opening a new era of economic and competitive growth in the Industrial Revolution known as "Industry 4.0". IIoT is able to help organizations achieve better benefits in industrial manufacturing markets by increasing productivity, reducing costs and developing new services and products. In this paper we present a wireless industrial communication system based on Node-RED platform using Modbus protocol for smart factories. [ABSTRACT FROM AUTHOR]

Many Wireless Sensor Networks (WSN) protocols such as lot of localization protocols rely on the accuracy of the Received Signal Strength Indicator (RSSI). This RSSI metric is sensitive to different factors which lead to its disturbance. Other works have already proved that temperature and humidity have important impact on RSSI in outdoor environment. It is evident that temperature and humidity vary more importantly on outdoor than on indoor. In this paper, we aim to answer at this question: Does the slight modification of temperature and humidity in indoor environment have a significant impact on RSSI value? We have conducted various experiments to study this impact. [ABSTRACT FROM AUTHOR]

Wireless sensor networks (WSNs) have astounding advantages for monitoring environmental properties and object movement. The small size of sensors in a WSN is used very craftily and is ideal for obscured observations. However, for these observations, the sensor clocks should be synchronized within a few microseconds of each other to accurately determine the point of origin. This paper shows the performance analysis of different time synchronization protocols over different mote platforms. Time synchronization protocols like Reference Broadcast Synchronization (RBS), Timing-Sync Protocol for Sensor Networks (TPSN), Hybrid Energy-Aware protocol and Minimum Distance Clustering Hybrid Synchronization (MDCHS) protocol are simulated over different mote platforms viz., MICA2Dot433, MICA2Dot916, MICAz and TelosB. Different performance metrics like Energy Usage and Synchronization Time are used to analyse the performance of these protocols. The model is simulated using MATLAB. The effects of changes in network topology and node density are also studied. [ABSTRACT FROM AUTHOR]

A lot of research is being done on the development of effective Network Intrusion Detection Systems. Anomaly based Network Intrusion Detection Systems are preferred over Signature based Network Intrusion Detection Systems because of their better significance in detecting novel attacks. The research on the datasets being used for training and testing purpose in the detection model is equally concerned as better dataset quality can advance offline Intrusion Detection. Benchmark datasets like KDD99 and NSL-KDD cup 99 are outdated and face some major issues, which make them unsuitable for evaluating Anomaly based Network Intrusion Detection Systems. This paper presents the statistical analysis of labelled flow based CIDDS-001 dataset using k-nearest neighbour classification and k-means clustering algorithms. The analysis is done with respect to some prominent evaluation metrics used for evaluating Network Intrusion Detection Systems including Detection Rate, Accuracy and False Positive Rate. [ABSTRACT FROM AUTHOR]

We investigate the pairwise error probability (PEP) performance degradation of dual phase multiple relay C(0) cooperation protocol due to imperfect channel state information (CSI) and mobility of nodes. We analyze PEP performance of C (0) protocol over time selective independent, but not identically distributed MIMO channel fading links. Our analysis reveals that because of the mobility of nodes, the PEP performance is severely degraded and in some specific system conditions, encounter asymptotic floor. Moreover, when both the destination-node (DN) and the source-node (SN) are static, the PEP upper union bound performance does not experience error floor limit regardless of the fact that the relay-nodes (RNs) are mobile. In addition, except the scenario when the RNs are static, the mobility of either the DN or the SN basically influences the performance of the wireless network due to error floors limits. Simulation outcomes prove that system achieves full diversity order (DO) when all nodes are static and perfect CSI. Simulation outcomes confirm the accuracy of the derived theoretical formulations. [ABSTRACT FROM AUTHOR]

With rapidly increasing interest in distributed real-time database systems (DRTDBS), data conflicts amongst distributed transactions have become a crucial factor which negatively influences the system performance. To address above issue, an I mproved Data Lending based D istributed R eal-Time C ommit (IDRC) protocol has been developed. IDRC reduce the negative impact of data conflicts on the DRTDBSperformance by increasing the data accessibility as compared to the earlier protocols. It allows the commit dependent borrower participant node (who has already lent the data item to the abort dependent borrower participant node) to lend the same data item in read mode to more than one borrower participant nodes. The simulation results show that the proposed commit protocol outperforms. [ABSTRACT FROM AUTHOR]

The main goal of the research consists in the elaboration of a system concerning the investigation of security communication, which regards a set of security factors, such as: the degree of encryption, the freshness of nonces, intruder activation, the lifetime of keys, secrets, etc. This paper is devoted to the presentation of systematization formalisms describing the functioning of a security model. In our variant, we investigate the changes of all chosen factors (security attributes) during the realization of protocol operations. The security attributes should be systematically corrected in this process. It changes the general security level of communication. The audit system strategy leads us to one of the most noticeable security in fluence characteristics that refer to time parameters. We can introduce the notation concerning the lifetime of elements (key, message, nonces, secret, etc.). When the value of time activity of an element exceeds its lifetime, then the communication security is definitely threatened. By using special rules presented in the works of Burrows, and Needham 2 , among other authors, and by creating additional logic formulas, we can estimate intermediate security probability parameters. Finally, we propose a certain kind of probability time automata in order to investigate and predicate different types of communication threats. These automata are built on the basis of a colored Petri net. In addition, this investigation consists in checking communication security (or a kind of threats) and making a threat prediction about possible cases that are connected with losing information. We also included in the model a procedure of security modification with respect to time (the activity of some parameters depends on time). We define the finite set of states by using the LU - technique (interval attribute activity) of a date notation. The proposed system resolves security problem in more comprehensive (multifaceted) way. Ingredient security factors can be grouped in different combinations. This approach increased the range of investigated threaten structures to even unknown hacker algorithm inventions. [ABSTRACT FROM AUTHOR]

Changing the whole network into a software defined network (SDN) is impractical due to high replacement cost. Therefore, there exist SDN hybrid networks, where SDN switches and legacy switches coexist at the same time. In this paper, we propose an SDN hybrid network architecture which can discover existence of legacy switches by using the Spanning Tree Protocol and thus have a global view of the SDN hybrid network. We also enable OpenFlow switches to cooperate with legacy switches by using the Learning Bridge Protocol without requiring any modification on legacy switches. By utilizing the characteristics of SDN, SDN applications can dynamically find routing paths according to pre-defined QoS requirements and current network status. We also propose a simulated annealing based QoS-aware routing (SAQR) algorithm which can adaptively adjust weights of delay, loss rate and bandwidth requirements in a cost function to find the best fit path according to QoS requirements. We evaluate the proposed SAQR in a simulated SDN hybrid network which runs applications with different QoS requirements. Simulation results show that the SAQR performs better than related work MINA in terms of the fitness ratios of delay, loss rate and bandwidth, with 88%, 90.8% and 86.5% of flows meeting their respective QoS requirements, in contrast to MINA, with only 63%, 82.4% and 87.5% of flows meeting their respective QoS requirements. [ABSTRACT FROM AUTHOR]

Abstract: Over the last few years, the Internet of Things (IoT) has grown in protocols, implementations and use cases. In terms of communication protocols, the Constrained Application Protocol (CoAP) stands out among the rest. This is extremely lightweight and capable of running in resource constrained devices and networks. There exist many implementations of CoAP, each of these with its own particular features and requirements. Therefore, it is important to choose the CoAP implementation that suits better to the specific requirements of each application. This paper presents a feature and empirical comparison of several open source CoAP implementations. First of all, it surveys current CoAP implementations, and compares them in terms of built-in core, extensions, target platform, programming language and interoperability. Then, it analyzes their performance in terms of latency, memory and CPU consumption in a real testbed deployed in an industrial scenario. [ABSTRACT FROM AUTHOR]

Abstract: Full duplex wireless communication is one of the enabling technologies of the fifth generation (5G) mobile telecommunication networks. It boosts up the bandwidth by enabling simultaneous data transmission and reception on a single channel. In this paper, we design a suitable medium access control (MAC) protocol for 5G networks to realize the benefit of full duplex communication. We also develop an analytical model to evaluate the performance of our proposed MAC protocol. [ABSTRACT FROM AUTHOR]

Abstract: A high rate of historical accidents on public roads motivated the advent of the Wireless Acces in Vehicular Environment (WAVE) standard. The main objective of WAVE was to develop strategies and protocols to enable inter-vehicular communication in view to reduce accident on public roads. Moreover, a successful message exchange can only be possible if the transmission medium is collision free. Under the Intelligent Transportation System (ITS), the cooperative Awareness messages (CAM) have to be transmitted at the rate of 10 Hz as per standard. To account for congestion management, the Distributed Congestion Control (DCC) mechanism was proposed. However, under higher node density, the DDC becomes inefficient and dramatically contribute to the deterioration of the VANET environment. The present work proposes a Dynamic Broadcast Storm Mitigation Algorithm (DBSMA) which can be used to combat the broadcast storm problem in a Vehicular Network (VN). Results from several simulations confirmed that the DBSMA has a potentiality to conquer the effect of broadcast storm by offering higher robustness compared to DCC with about 130% improved efficiency. Beside its computational simplicity, the DBSMA is easy to implement. [ABSTRACT FROM AUTHOR]

Distributed computing infrastructures (DCI) play an important role in modern research by enabling the use of multiple computing resources for solving complex problems. Despite the expansion of large-scale DCIs, the rapid integration of resources into ad-hoc infrastructures for small research projects or personal use still remains a challenge. The paper describes the integration and combined use of resources with Everest, a web-based distributed computing platform. In contrast to existing solutions, Everest follows the PaaS model and can be used remotely by multiple users to seamlessly run computations on arbitrary combinations of external resources attached by users. The integration of Everest with standalone resources and EGI grid is described. The presented approach is demonstrated by running real-world applications on ad-hoc infrastructures consisting of resources of different types. [ABSTRACT FROM AUTHOR]

OBJECTIVE: The objective of this paper is to investigate the goals and variables employed in the machine learning and microsimulation studies for the prognosis of dementia. METHOD: According to preset protocols, the Pubmed, Socups and Web of Science databases were searched to find studies that matched the defined inclusion/exclusion criteria, and then its references were checked for new studies. A quality checklist assessed the selected studies, and removed the low quality ones. The remaining ones (included set) had their data extracted and summarized. RESULTS: The summary of the data of the 37 included studies showed that the most common goal of the selected studies was the prediction of the conversion from mild cognitive impairment to Alzheimer's Disease, for studies that used machine learning, and cost estimation for the microsimulation ones. About the variables, neuroimaging was the most frequent used. CONCLUSIONS: The systematic literature review showed clear trends in prognosis of dementia research in what concerns machine learning techniques and microsimulation. [ABSTRACT FROM AUTHOR]

One of the crucial aspects of the Internet of Things that influences the effectiveness of communication among devices is the communication model, for which no universal solution exists. The actual interaction pattern can in general be represented as a directed graph, whose nodes represent the “Things” and whose directed edges represent the sent messages. Frequent patterns can identify channels or infrastructures to be strengthened and can help in choosing the most suitable message routing schema or network protocol. In general, frequent patterns have been called motifs and overrepresented motifs have been recognized to be the low-level building blocks of networks and to be useful to explain many of their properties, playing a relevant role in determining their dynamic and evolution. In this paper triadic motifs are found first partitioning a network by strength of connections and then analyzing the partitions separately. The case study is the World Trade Web (WTW), that is the directed graph connecting world Countries with trade relationships, with the aim of finding its topological characterization in terms of motifs and isolating the key factors underlying its evolution. The WTW has been split based on the weights of the graph to highlight structural differences between the big players in terms of volumes of trade and the rest of the world. As test case, the period 2003-2010 has been analyzed, to show the structural effect of the economical crisis in the year 2007. [ABSTRACT FROM AUTHOR]

Mobile Ad hoc Network (MANET) is a rapidly growing wireless technology with wide range of applications. MANET routing faces challenges due to their Ad hoc nature, and many routing algorithms have been proposed. Reactive routing protocols are preferred due to less control overhead and scalability, but they suffer from frequent link breakages due to the high-mobility of the nodes. To reduce the link breakages and get a stable route, a new reactive routing protocol is proposed that is tree-based mobility-aware. The proposed Mobility and Direction Aware Ad-hoc On Demand Distance Vector routing protocol (MDA-AODV) aims to handle the mobility and direction factors in ad-hoc networks. MDA-AODV guides the route discovery and route reply depending on the speed of the participating nodes and their directions. Qualnet simulator version 7.1, using two offered load simulations (packet-rate and CBR connections), was used to investigate the effect and the advantages of MDA-AODV over AODV protocol. The simulation results show that the proposed scheme decreases control overhead by (4.6 ÷ 5.2%). It also accomplishes (37 ÷ 41%) lower route losses compared to AODV. The delivery ratio is increased by (29 ÷ 47%). The consumed energy and end-to-end delay of the proposed protocol is also compared to that of AODV. [ABSTRACT FROM AUTHOR]

Many of the communication protocols developed for the resource constrained devices are rarely subjected to protocol verification. Design flaws like deadlocks, livelocks, non-progressive cycles etc. may come into view during the realization and can cause catastrophic effects in safety-critical applications. Formal specification of the protocol represented as a model helps to describe and analyse the conformability of the implementation to its specification and subsequently reveal design flaws, if any in the system. The formal model is subject to verification by inserting correctness and safety properties of the protocol and validating logical correctness using a model checking tool. All model checkers suffer from state explosion problem due to enormous states of the model being created. The key contribution of the present work is the introduction of a method to develop a compact verification model which is amenable to full state space search by abstracting the key elements of a protocol. Moreover, many protocol verification works presented in the existing literature consider only a single layer of a communication protocol. To correctly model the overall behaviour of a protocol, interactions between the layers have to be incorporated. The proposed method has been proven useful by considering verification of an application protocol, CoAP for constrained devices by abstracting out the aspects of the underlying routing protocol RPL. Reliable message exchanges among various entities are modeled and its safety and correctness properties were analysed and verified. The results obtained show that the model performs the full state space search by considering all possible routing paths and are free from design flaws. The method described has been implemented by building a validation model in PROMELA and the model is verified by using SPIN model checker. The methodology used in this paper can be used to verify any application layer protocol for constrained devices in IoT scenario that run on top of routing layer. [ABSTRACT FROM AUTHOR]

This paper presents the design and implementation of a lightweight node authentication protocol which comprises of node registration, node authentication and key establishment phases. The solution leverages the low computational overheads associated with cryptographically secure one-way hash chains and Elliptical Curve Crytography (ECC) without using any digital signature algorithm or any public key cryptography. The usage of hidden generator point derived from hash-chains provides defense against a man-in-the-middle attack which is prominent in ECDH (Elliptical Curve Diffie-Hellman) due to lack of entity authentication. The authentication protocol has been simulated on Tossim and its performance bench marking has also been carried out. [ABSTRACT FROM AUTHOR]

Many applications of Wireless Sensor Networks such as Airborne Ad-hoc Networks (AANETs) or Underwater Wireless Sensor Networks (UWSNs) require the network architecture to be three-dimensional. In this paper, we present a terrestrial three-dimensional network architecture as well as protocol stack deployment for static sensor nodes placed at varying heights. A Dynamic Cluster-Based TDMA MAC (DCB-TDMA MAC) protocol has been developed for this network and simulated using Cooja platform. Cluster-Head nodes are rotated based on residual energy in order to maximize the lifetime of the network. Detailed working of protocol involving Time Synchronization, MAC, Cluster-Head rotation, Dynamic Routing is provided in this paper along with simulation results and analysis. [ABSTRACT FROM AUTHOR]

As VLSI technology advances, the number of modules on a chip multiplies and thus the solutions for on-chip communication are evolving to support the new paradigm in inter-module communication on System on Chip (SOC). Those System on Chip, Current chip designs incorporate more complex multilayered and stack segmented interconnection buses with various routing architectures results in a Network on Chip. These, traditional solutions, which were based on a combination of shared-buses and dedicated module-to-module wires, scalability limit, and are no longer adequate for System on Chip/Network on Chip. On-chip architectures have been optimized for a non-chip environment before the multi-core challenge became the focus of processor chip architecture through the latency and the throughput. This evolution of on-chip interconnects may evoke feelings of among networking old-timers. The considerations that have driven data communication from shared buses to packet-switching networks and to routing protocols such as spatial reuse, multi-hop routing, flow and congestion control etc., will inevitably drive the challenges raised in the design of network interfaces with the segmented stack layered mechanism, and potentially managing the critical resources designed for on-chip modules. [ABSTRACT FROM AUTHOR]

Digital Signatures are primarily employed to achieve data integrity, data origin authentication and non-repudiation. In comparison to RSA-based digital signatures, the ECC (Elliptical Curve Cryptography) based Signature schemes like ECDSA (Elliptical Curve Digital Signature Algorithm) are more efficient and suited for a resource-constrained network like WSN. In a WSN, proper entity authentication is to be achieved before the sensor data is exchanged. The use of ECDSA is not suitable for achieving mutual authentication between the entities like the base station, cluster heads and nodes. Based on the study of ECDSA, the paper designs a mutual authentication protocol with the help of a computationally low signature scheme. To the best of our knowledge, this is the first digital signature based scheme which achieves mutual entity authentication. The paper also brings out performance parameters of the developed protocol. [ABSTRACT FROM AUTHOR]

Vehicular Sensor Network (VSN) emerged due to recent developments in Wireless Sensor Network (WSN) and functioning as a way for observing metropolitan environments and enabling vehicles to share relevant sensor data to assist safety, convenience and commercial applications. Data dissemination is an important aspect of these networks and requires timely delivery of important sensor information. In VSNs, rapid mobility of the vehicles causes recurrent topography modifications. The possibility of on-demand protocols that makes routing decisions reactively in Vehicular Networks are restricted owing to its structural instability and current routing protocols, operating in a table-driven fashion like OLSR are unable to cope up with the high demands imposed by vehicular applications. Furthermore, sensor data transmissions are accompanied by rapid fluctuations in the convention of licensed spectrum and acquire more number of channels to transmit huge bandwidth data and result in spectrum scarcity. Existing works on OLSR protocol failed to examine spectrum conditions and calculate utilization of channel. Cognitive Radio (CR) is a possible solution for guiding OLSR to discover unused frequency bands and utilize them opportunistically. This paper presents an optimal OLSR routing for efficient data communication using Cognitive Radio enabled Vehicular Sensor Networks (CR-VSNs). The proposed model was tested under simulated traffic of Chennai urban road map. Delay is observed to be minimal for data communications in CR-VSN. [ABSTRACT FROM AUTHOR]

This paper presents the design of triple band compact microstrip patch antenna with fractal elements. The antenna has been designed on FR4 substrate with thickness 1.6mm, dielectric constant 4.4 and resonant frequency of antenna is 3.2GHz. Gain of antenna is improved by addition of fractal elements to the nine corners of the nonagon patch. Introduction of fractal elements improved the gain from 1.24dB to 7.96dB and miniaturization takes place due to the decrease in resonant frequency from 3.38GHz to 2.88GHz on increasing the iteration number. The three iterations of antenna is designed and simulated by using HFSS V13 software and the designed antennas covers the frequency bands of WLAN, WiMax and other wireless applications which comes under the frequency ranges of S-band, C-band and X-band. [ABSTRACT FROM AUTHOR]

The CoRE working group at the IETF has proposed a Resource Directory (RD) solution to facilitate the discovery of the resources provided by constrained wireless sensor and actuator networks. For such a mechanism to be effectively deployable, nodes must first discover the existence of an RD in the network before being able to exploit its functionalities. This paper presents Proactive RD Discovery (PRD); a scalable, reliable, and effective mechanism to discover an RD. To achieve such qualities, the proposed mechanism deploys adaptive Trickle timers. PRD is implemented in Contiki OS and evaluated using emulated sensor/actuator nodes in the Cooja simulator. Simulation results show important performance enhancements in terms of energy consumption, generated traffic, RD discovery time, and reliability when compared with the default discovery mechanism bundled with the RD. [ABSTRACT FROM AUTHOR]

The increased application of wireless technologies including Wireless Sensor Actuator Networks (WSAN) in industry has given rise to a plethora of protocol designs. These designs target metrics ranging from energy efficiency to real-time constraints. Protocol design typically starts with a requirements specification, and continues with analytic and model-based simulation analysis. State-of- the-art network simulators provide extensive physical environment emulation, but still have limitations due to model abstractions. Deployment testing on actual hardware is therefore vital in order to validate implementability and usability in the real environment. The contribution of this article is a deployment testing of the Dual-Mode Adaptive MAC (DMAMAC) protocol. DMAMAC is an energy efficient protocol recently proposed for real-time process control applications and is based on Time Division Multiple Access (TDMA) in conjunction with dual-mode operation. A main challenge in implementing DMAMAC is the use of a dynamic superframe structure. We have successfully implemented the protocol on the Zolertia Z1 platform using TinyOS (2x). Our scenario- based evaluation shows minimal packet loss and smooth mode-switch operation, thus indicating a reliable implementation of the DMAMAC protocol. [ABSTRACT FROM AUTHOR]

In this work, we describe a security solution that can be used to securely establish mobile payment transactions over the Near-Field Communication (NFC) radio interface. The proposed solution is very lightweight one; it uses symmetric cryptographic primitives on devices having memory and CPU resources limitations. We show that our approach maintains the security of NFC communications and we further demonstrate that our solution is simple, scalable, cost-effective, and incurs minimal computational processing overheads. [ABSTRACT FROM AUTHOR]

Several studies in the past have revealed that network end user devices are left powered up 24/7 even when idle just for the sake of maintaining Internet connectivity. Network devices normally support low power states but are kept inactive due to their inability to maintain network connectivity. The Network Connectivity Proxy (NCP) has recently been proposed as an effective mechanism to impersonate network connectivity on behalf of high power devices and enable them to sleep when idle without losing network presence. The NCP can efficiently proxy basic networking protocol, however, proxying of Internet based applications have no absolute solution due to dynamic and non-predictable nature of the packets they are sending and receiving periodically. This paper proposes an approach for proxying Internet based applications and presents the basic software architectures and capabilities. Further, this paper also practically evaluates the proposed framework and analyzes expected energy savings achievable under- different realistic conditions. [ABSTRACT FROM AUTHOR]

This paper provides a comprehensive and rigorous study of a novel collision resolution algorithm for wireless sensor networks: 2CS-WSN. It is specifically designed to be used during the contention phase of IEEE 802.15.4. This algorithm has been modelled in terms of discrete time Markov chains (DTMCs) and, using the probabilistic symbolic model checker PRISM, correctness properties and different operation modes of the algorithm have been studied. Moreover, different model abstractions have been used in order to identify any inconsistencies or ambiguities, and to prove interesting properties for non-trivial, practical and relevant scenarios. Finally, since the biggest source of energy waste is the collision, this paper conducts a wide study of energy saving in this algorithm. [ABSTRACT FROM AUTHOR]

MANET stands for Mobile ad hoc network and is an infrastructure-less network and it is having ability to configure itself. The topology of network changes dynamically. It consists of wireless mobile nodes which communicate with each other without any centralized administration. In MANET different types of routing protocols are introduced. These protocols can be categorized into reactive, proactive and hybrid routing protocols. In this paper, AODV and DSDV protocols are analyzed in terms of routing overhead, packet delivery ratio, throughput and end to end delay. The performance of AODV is better than DSDV in terms of throughput, packet delivery ratio and routing overhead. As the DSDV is a proactive routing protocol, it is having a less end to end delay as compare to AODV. The performance of AODV gets affected by black hole attack. This paper gives the modification in AODV which helps to improve the performance of AODV in presence of black hole attack. [ABSTRACT FROM AUTHOR]

Opportunistic routing is a new paradigm in routing for wireless sensor network which chooses the node closest to the target node for forwarding the data. It uses the broadcasting nature of wireless sensor networks. Opportunistic routing has increased the efficiency, throughput and reliability of sensor networks. Many energy saving techniques has been introduced using opportunistic routing in wireless sensor networks for increasing the network lifetime. In this article we have elaborated the basic concept of Opportunistic routing, different areas in which it has been claimed to be beneficial, some protocols their metrics and their drawbacks. [ABSTRACT FROM AUTHOR]

Internet of Things is future trend that assure to enhance and upgrades our everyday living by utilizing intelligent objects and sensors collectively. These devices are supposed to make use of constrained application protocol (CoAP) to communicate at application layer. Communication security is mainstay of constrained environments. Confidential communication within constrained devices will be carried out by secure CoAP (CoAPs) which makes use of DTLS protocol. To cope with constrained devices we use integration of CoAP and DTLS compressed by following 6LoWPAN standards. Compressed DTLS minimizes packet size and possibly avoids fragmentation. In addition to this we used the raw public key concept over DTLS to authenticate the multivendor constrained devices. Evaluation results shows that CoAPs with Raw Public Key provides communication security and authentication portability in multivendor environment at minimal energy consumption. CoAPs with Raw Public Key improves the interoperability as well as lifetime of network. [ABSTRACT FROM AUTHOR]

For privacy protection, many architectures such as trusted third party, cryptography, client side privacy etc. have been proposed. These methods are neither fully support privacy nor efficient. We have proposed limited broadcast based application and one dynamic protocol for cloaking. We have simulated user broadcast model, to achieve location privacy where users are mobile and points of interests (POI) are stationary. Second experiment is a POI broadcast model to achieve location privacy. We have also presented dynamic cloaking protocol that considers speed, direction & location of mobile user for cloaking. We have experimentally recorded the results related to performance, energy and privacy strength. It shows that our system has more social and human value along with commercial attraction. [ABSTRACT FROM AUTHOR]

Security is an important issue in our everyday life. System based on different wireless protocol standards is vulnerable to security threats. This Paper is giving glance on security issues arises in object tracking system; and to deal with that, provide comparative analysis between various cryptographic techniques for selecting best one among all. The use of 128 bit PRNG and XOR protocol across RFID system and applying Binary ECC while sending data via GSM communication will surely boost up safety measures of object tracking system as depicted in this paper. [ABSTRACT FROM AUTHOR]