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In this study, the authors propose a backstepping‐based, distributed formation control method that is stable independent of time delays in communication among multiple unmanned aerial vehicles (UAVs). Centralised formation control of UAVs requires each agent to maintain a separation distance from other agents, which burdens the communication network of the UAVs. To overcome this problem, the authors consider a distributed control scheme wherein each agent updates its attitude and position based on the state information gathered through its neighbours. Instead of directly controlling the thrust generated by the propellers, they partition the mathematical model of the UAV into two subsystems, a linear attitude control loop and a non‐linear position control loop. A backstepping‐based outer position controller is then designed that interfaces seamlessly with the inner attitude controller of the cascaded control system. The closed‐loop stability is established using a rigorous Lyapunov–Krasovskii analysis under the influence of distributed network time delays. Using the directed graph topology and a distributed backstepping structure, it is shown that the stability criterion is delay‐independent. The proposed control algorithms are verified in simulation and then implemented in hardware, and actual flight test experiments prove the validity of these algorithms. [ABSTRACT FROM AUTHOR]

This paper studies a leader-following consensus problem of continuous-time double-integrator multi-agent systems with measurement noises and time-varying communication delays under directed topology. By utilising the neighbour position and velocity information, which are delayed and disturbed by measurement noises whose intensities are considered a function related to the neighbour position and velocity of agents, a distributed consensus protocol is presented, sufficient conditions of the tracking consensus in the sense of mean square are derived. Finally, the effectiveness of the proposed consensus protocol is proved by some simulations. [ABSTRACT FROM AUTHOR]

A new general hybrid neural networks with inertial term and mixed time-varying delays are proposed here by using the memristors connections. Then by building appropriate Lyapunov functionals and inequality technique, some new conditions assuring the global exponential stability of the hybrid neural networks are derived. The circuit implementation of the proposed hybrid neural networks are also presented here. In addition, the new proposed results here enrich and extend the earlier publications on neural networks. Lastly, numerical simulations show the effectiveness of our results. [ABSTRACT FROM AUTHOR]

Most of the existing work on topology control is to minimize the interference or delay separately. However, minimizing the interference and reducing the delay are two conflicting goals; therefore, considering a trade-off between them is necessary. In this paper, our goal is to minimize the interference while guaranteeing the end-to-end delay under a constraint. We take into account three optimization objectives, including the maximum interference, average interference and average path interference. We propose a centralized algorithm with a greedy strategy that can minimize the maximum interference while satisfying the delay constraint. A distributed algorithm (LDMST) is proposed to minimize the average interference. In LDMST, each node builds a delay-constrained minimum spanning tree (DMST). To minimize the path interference, a localized delay-constrained Bellman–Ford (LDBF) algorithm is proposed. LDBF employs an improved Bellman–Ford algorithm to find the optimal path, which has the minimum interference and satisfies the delay constraint. The final topology is composed of these optimal paths. The simulation results illustrate that the proposed topology control algorithms exhibit good performance in terms of the interference objectives and can also guarantee the end-to-end delay under the constraint. [ABSTRACT FROM AUTHOR]

To extend the network coverage to rural and remote areas, there are different solutions with their advantages and disadvantages. We propose to use a nanosatellite network and to exploit the ability to cope with large delays and disruptions provided by the delay- and disruption-tolerant networking (DTN) paradigm. The connection from remote areas is managed through ground stations called cold spots that collect data from rural nodes and address them to the nanosatellites. Nanosatellites carry and download data to hot spots that address them to the Internet destinations. On the reverse direction, Internet data are addressed to hot spots, uploaded on nanosatellites and delivered to the rural destinations through cold spots. The problem of choosing the “optimal’’ hot spot to address data from the Internet source is important because a wrong choice could lead to large delivery delays. In this paper, we propose “gRANteD’’: a Nanosatellite-DTN Network for rural and remote areas. gRANteD includes “HotSel,’’ a hot spot selection algorithm to minimize the delivery time of all data destined to rural users. The performance evaluation is carried out through a DTN module which implements gRANteD and HotSel, within the framework of Network Simulator 3. [ABSTRACT FROM PUBLISHER]

This paper addresses the dynamic output feedback control problem for a class of discrete system with uncertainties and multiple time-delays. First, the system is decomposed into two subsystems based on the output matrix and input control matrix. Secondly, a dynamic compensator is employed for the first subsystem, and then, given the multiple uncertainties, the output feedback controller is designed based on the second subsystem and the dynamic compensator. Thirdly, by choosing the Lyapunov-Krasovskii function, it can be seen that the developed controller makes the closed-loop system convergent to an adjustable region, which can be rendered arbitrary small by adjusting design parameters. Compared with the previous researches, the proposed controller is not only smooth and memoryless, but also only dependent on the system output. Furthermore, with the given dynamic compensator, the controller design conditions are relaxed, while the approach is extended to the conventional nonlinear system. Finally, numerical example is given to illustrate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

This paper deals with the problem of delay-dependent robust $$H_\infty $$ control for uncertain systems with time-varying delays and norm-bounded parameter uncertainties. Firstly, some new delay-dependent stability criteria are proposed by exploiting a new Lyapunov-Krasovskii functional and free-weighting matrices method. Secondly, based on the criteria obtained, a delay-dependent criterion for the existence of a memoryless state feedback $$H_\infty $$ controller that ensures asymptotic stability and a prescribed $$H_\infty $$ performance level of the closed-loop system for all admissible uncertainties is proposed in terms of linear matrix inequalities (LMIs). These developed results enjoy much less conservatism than the existing ones due to the introduction of delay segmentation approach to estimate the upper bound of the derivative of Lyapunov functional without ignoring some useful terms that take into account information of the time-delay. Finally, numerical examples are provided to demonstrate the effectiveness and benefits of the proposed method. [ABSTRACT FROM AUTHOR]

Cyber-Physical Systems (CPS) present the greatest challenges but also the greatest opportunities in several critical industrial segments such as electronics, automotive and industrial automation. Governing the complexity and design correctness issues of CPS software requires methodologies and tools that address the problems of intrinsic concurrency and timing constraints over a large spectrum of CPS architectures. In this paper we present DTRON, a framework for model-based testing that addresses the issues of distributed execution and real-time constraints imposed by the design of networked CPS. DTRON extends the Uppaal model checking tool and online test execution tool TRON enabling coordination, synchronization, and online distributed testing. The notion of Δ-testability required to guarantee the controllability of distributed tests is one of the main design considerations for DTRON. The core part of the paper presents the architectural solutions for implementing DTRON and then special focus is put on the performance evaluation of the tool taking into account the communication and test adapter delays in networked systems. We demonstrate that the co-use of Spread message serialization service and Network Time Protocol allows reducing Δ down to the 1 ms range, which is sufficient for testing timing properties of a substantial class of networked CPS. We exemplify the applicability of DTRON with three distributed testing case studies, namely, city street light controller network, interbank trading system, and robot navigation system. [ABSTRACT FROM AUTHOR]

Although there is a plethora of literature dealing with Phasor Measurement Unit (PMU) communication delay, there has not been any effort made to generalize empirical delay results by identifying the distribution with the best fit. The existing studies typically assume a distribution or simply build on analogies to communication network routing delay. Specifically, this study provides insight into the characterization of the communication delay of both unprocessed PMU data and synchrophasors sorted by a Phasor Data Concentrator (PDC). The results suggest that a bi-modal distribution containing two normal distributions offers the best fit of the delay of the unprocessed data, whereas the delay profile of the sorted synchrophasors resembles a normal distribution based on these results, the possibility of evaluating the reliability of a synchrophasor application with respect to a particular choice of PDC timeout is discussed. [ABSTRACT FROM AUTHOR]

In this article, a delayed complex network model with non-identical nodes is established, where the mismatched uncertain parameters are involved in each node. The concept of approximate synchronization is proposed. A linear feedback controller is designed and a sufficient condition for boundedness of the synchronous error is presented in terms of linear matrix inequalities. A pseudoconvex optimization problem for minimizing the upper bound of the synchronous error is proposed. Furthermore, an iterative algorithm involving convex problem is designed to solve this pseudoconvex optimization problem and obtain the globally optimal solution, by which the approximate synchronization is achieved. At last, two numerical examples are given to show the effectiveness of the proposed criterion. [ABSTRACT FROM AUTHOR]

Abstract: This paper’s aim is to present a novel distributed estimation technique for linear time-invariant systems with network-induced delays and packet dropouts. The methodology is based on local Luenberger-like observers in combination with consensus strategies. Only neighbors are allowed to communicate and the observer design contemplates the possibility of sharing only a subset of the estimates. The design problem is solved via linear matrix inequalities and an asymptotic stability proof is provided. [Copyright &y& Elsevier]

Abstract: This paper considers the synchronization problem for coupled neural networks with interval time-varying delays and leakage delay. By construction of a suitable Lyapunov–Krasovskii’s functional and utilization of Finsler’s lemma, novel delay-dependent criteria for the synchronization of the networks are established in terms of linear matrix inequalities (LMIs) which can be easily solved by various effective optimization algorithms. Two numerical examples are given to illustrate the effectiveness of the proposed methods. [Copyright &y& Elsevier]

Abstract: A generalized model of the two-neuron network with mixed delays is studied. The main purpose of this paper is to explore the linear stability of the trivial solution and Hopf bifurcation of a two-neuron network with continuous and discrete delays. The general formula of the direction, the estimation formula of period and stability of bifurcated periodic solutions are also studied. Finally, the numerical simulations are given to illustrate the theoretical analysis. [Copyright &y& Elsevier]

Abstract: This paper proposes new results for the existence, uniqueness and global asymptotic stability of the equilibrium point for neural networks with multiple time delays under parameter uncertainties. By using Lyapunov stability theorem and applying homeomorphism mapping theorem, new delay-independent stability criteria are obtained. The obtained results are in terms of network parameters of the neural system only and therefore they can be easily checked. We also present some illustrative numerical examples to demonstrate that our result are new and improve corresponding results derived in the previous literature. [Copyright &y& Elsevier]

Machine-to-machine (M2M) networks could be connected by a wide range of wireless technologies (e.g., Bluetooth,WiFi, RFID). Due to some factors (e.g., mobility of machines, limited communication range), it is hard to maintain the connectivity of the network, that is, the network is disconnected and it is a specific application of delay tolerant networks (DTN). Communication in such network often needs nodes working in a cooperative way. However, due to selfishness, nodes have no incentive to help others. Therefore, if the source requests help from other nodes, it needs to pay certain fees to them. The main goal of this paper is to explore efficient ways for the source to maximize the average delivery ratio when the total fees are limited. First, we mathematically characterize the average delivery ratio under different policies. Then we get the optimal policy through Pontryagin's maximum principle, and prove that the optimal policy conforms to the threshold form when the fees that other nodes require satisfy certain conditions. Simulations based on both synthetic and real motion traces show the accuracy of our model. Through extensive numerical results, we demonstrate that the optimal policy obtained by our model is the best. [ABSTRACT FROM AUTHOR]

Due to intrinsic properties of aqueous environments, routing protocols for underwater wireless sensor network (UWSN) have to cope with many challenges such as long propagation delay, bad robustness, and high energy consumption. Basic ant colony optimization algorithm (ACOA) is an intelligent heuristic algorithm which has good robustness, distributed computing and combines with other algorithms easily. But its disadvantage is that it may converge at local solution, not global solution. Artificial fish swarm algorithm (AFSA) is one kind of intelligent algorithm that can converge at global solution set quickly but has lower precision in finding global solution. Therefore we can make use of AFSA and ACOA based on idea of complementary advantages. So ACOA-AFSA fusion routing algorithm is proposed which possesses advantages of AFSA and ACOA. As fusion algorithm has aforementioned virtues, it can reduce existing routing protocols' transmission delay, energy consumption and improve routing protocols' robustness theoretically. Finally we verify the feasibility and effectiveness of fusion algorithm through a series of simulations. [ABSTRACT FROM AUTHOR]

We propose a hybrid data delivery method for the large-scale heterogeneous sensor networks, which is a fast and reliable delivery protocol for the aggregated data from the sinks to the GW. We develop a new multicriteria-ranking algorithm which determines multiple forwarders for each hop by ranking neighbor nodes. To rank the nodes, we compute the fitness value using features for each node such as the received signal strength, nodal delay, and hop distance. We determine the time of sending among forwarders using the waiting time assignment algorithm. In the experimental section, we show that our method outperforms conventional data delivery protocols in terms of data delivery ratio and end-to-end delay. [ABSTRACT FROM AUTHOR]

Wireless sensors are battery-limited sensing and computing devices. How to prolong the lifetime of wireless sensors becomes an important issue. In order to reduce the energy consumptions when nodes are in idle listening, duty-cycle-based MAC protocols are introduced to let node go into sleep mode periodically or aperiodically. The long duty cycle makes sensors increase the transmission throughput but consumes more energy. The short duty cycle makes sensors have low energy consumption rate but increases the transmission delay. In this paper, a dynamic traffic-aware MAC protocol for energy conserving in wireless sensor networks is proposed. The proposed MAC protocol can provide better data transmission rate when sensors are with high traffic loading. On the other hand, the proposed MAC protocol can save energy when sensors are with low traffic loading. Simulation results show that the proposed protocol has better data throughput than other duty-cycle-based MAC protocols, for example, S-MAC and UMAC. We also developed a set of comprehensive experiments based on the well-known OMNET++ simulator and revealed that our proposed TA-MAC performs significantly outstanding than related schemes under various situations. [ABSTRACT FROM AUTHOR]

The IEEE 802.15.4 standard provides Guaranteed Time Slot (GTS) mechanism for reliable transmission. GTS mechanism is suitable for transmitting time-sensitive data because it allocates time slots to a specific node. However, the GTS mechanism in the standard can be used only for one-hop communication. This paper proposes and implements a multihop GTS mechanism for reliable transmission in multihop networks. Simulation results using NS-2 show that low delay and high delivery ratio can be achieved using the proposed mechanism. [ABSTRACT FROM AUTHOR]

Routing and spectrum allocation is an important challenge in cognitive wireless mesh networks. A distributed routing and spectrum allocation algorithm with cooperation (DRSAC-W) in cognitive wireless mesh networks is proposed in this paper. In order to show the decrease of the average end-to-end delay with cooperation in DRSAC-W, a distributed routing and spectrum allocation algorithm without cooperation (DRSAC-WO) is proposed in this paper. Minimizing the average end-to-end delay is the objective of DRSAC-W and DRSAC-WO. Simulation results show that the proposed algorithm DRSAC-W with cooperation can alleviate the high delay due to the heterogeneity of available channels of different nodes and achieve low average end-to-end delay. [ABSTRACT FROM AUTHOR]

Ubiquitous use of cell phones encourages development of novel applications with sensors embedded in cell phones. The collection of information generated by these devices is a challenging task considering volatile topologies and energy-based scarce resources. Further, the data delivery to the sink is delay tolerant. Mobility of cell phones is opportunistically exploited for forwarding sensor generated data towards the sink. Human mobility model shows truncated power law distribution of flight length, pause time, and inter-contact time. The power law behavior of inter-contact time often discourages routing of data using naive forwarding schemes. This work exploits the flight length and the pause time distributions of human mobility to design a better and efficient routing strategy. We propose a Human-Mobility-based Sensor Context-Aware Routing protocol (HMSCAR), which exploits human mobility patterns to smartly forward data towards the sink basically comprised of wi-fi hot spots or cellular base stations. The simulation results show that HMSCAR significantly outperforms the SCAR, SFR, and GRAD-MOB on the aspects of delivery ratio and time delay. A multi-sink scenario and single-copy replication scheme is assumed. [ABSTRACT FROM AUTHOR]

The paper proposes a routing scheme for IPv6-based all-IP wireless sensor networks. The paper creates the IPv6 address structure and the IPv6 address configuration algorithm for all-IP wireless sensor networks. Based on the IPv6 address structure, the paper proposes the routing algorithm in the link layer for all-IP wireless sensor networks. In the routing scheme, a sensor node stores the next channel-sampling time of its neighbor nodes. In this way, only during the next channel-sampling time, a sensor node keeps active. and during any other time it returns to sleep. Therefore, the routing performance is improved. and the power consumption is reduced. Finally, the paper discusses the reduced IPv6 protocol stack performing the routing scheme. The routing scheme's performance parameters are evaluated, including routing power consumption and delay, and the data results show the correctness and efficiency of the scheme. [ABSTRACT FROM AUTHOR]

We study the rendezvous data collection problem for the Mobile Element (ME) in heterogeneous sensor networks where data generation rates of sensors are distinct. The link quality is instable in our network model and the sensory data cannot be aggregated when transmitting. The Mobile Element is able to efficiently collect network wide data within a given delay bound; meanwhile the network eliminates the energy bottleneck to prolong its lifetime. For case study, we consider the trajectory planning for both Mobile Relay and Mobile Sink on a tree-shaped network. In the Mobile Relay case where the ME's trajectory must pass through a sink to upload sensory data for further processing, an O(n lg n) algorithm named RP-MR is proposed to approach (1) the optimal Rendezvous Points (RPs) to collect global sensory data; (2) the optimal data collection trajectory for the Mobile Relay to gather the cached data from RPs. In the Mobile Sink case where the Mobile Element can process the sensory on its motion, we develop an O(n lg2 n) algorithm named RP-MS to recursively investigate the optimal solution. Both the theoretical analysis and extensive simulations verify the correctness and effectiveness of proposals. [ABSTRACT FROM AUTHOR]

This work addresses a tough challenge of achieving two opposing goals: ensuring long lifetimes and supporting short end-to-end delays in sensor networks. Obviously, sensor nodes must wake up often to support short delays in multi-hop networks. As event occurs seldom in common applications, most wake-up are useless: nodes waste energy due to idle listening. We introduce a set of solutions, referred to as LETED (limiting end-to-end delays), which shorten the wake-up periods, reduce idle listening, and save energy. We exploit hardware features of available transceivers that allow early detection of idle wake-up periods. This feature is introduced on top of our approach to reduce idle listening stemming from clock drift owing to the estimation of run-time drift. To evaluate LETED and other MAC protocols that support short end-to-end delays we present an analytical model, which considers almost 30 hardware and software parameters. Our evaluation revealed that LETED reduces idle listening by 15x and more against similar solutions. Also, LETED outperforms other protocols and provides significant longer lifetimes. For example, nodes with LETED work 8x longer than those with a common TDMA and 2x-3x longer than with protocols based on preamble sampling, like B-MAC. [ABSTRACT FROM AUTHOR]

Exploitation of wireless communications in various automation applications brings indisputable benefits, which has proliferated research efforts in the field during the recent years. However, underlying wireless communication systems introduce problems to the wireless control systems, such as variable delays, information loss, and limited throughput. By using multiple frequency bands simultaneously, the performance of a wireless network can be enhanced. Since many control applications have strict requirements on delay and delay variations, it is important to understand the impact of communication systems on the performance of wireless automation systems with respect to delay. Hence, in this paper, we study how different communication parameters, such as packet arrival rate, number of channels, and packet size, affect the performance of control systems. We also derive bound on control system performance given the network properties. Our results show the tradeoff between the performance of the wireless multichannel communication system and the automation system. These results can, for example, be further exploited in system design to find out the maximum packet arrival rate with given control parameters. [ABSTRACT FROM AUTHOR]

As an important component of transportation system, public transportation accounts for a considerable proportion in the whole traffic flow. The public transportation vehicles can be categorized into two categories as follows: one with determinate trajectories and schedules such as bus, tramway, and light rail; the other with flexible and variable running paths, such as taxis. In this paper, we firstly present a destination-gathering-based driving path prediction method for taxis, which can make taxis' driving paths prescient in the initial stage of carrying passengers every time. Compared with ordinary vehicles, public transportation vehicles have such features as long time running on roads and no privacy-protection need, and thus their trajectories can be opened. Through utilizing the features above, we propose a novel public-transportation-assisted data delivery scheme (PTDD) used to improve the performance of data delivery of Vehicular Delay Tolerant Networks (VDTNs). Simulation results based on a real map demonstrate the effectiveness of the proposed scheme. [ABSTRACT FROM AUTHOR]

Routing protocol is an important topic in the wireless sensor networks. For MultiSink wireless sensor networks, the routing protocol designs and implementations are more difficult due to the structure complexity. The paper deals with the problem of a multiple-dimensional tree routing protocol for multisink wireless sensor networks based on ant colony optimization. The proposed protocol is as follows: (1) listening mechanism is used to establish and maintain multidimensional tree routing topology; (2) taking into consideration hops, packet losses, retransmission, and delay account, a distributed ant colony algorithm is proposed. When nodes select routes in the data transmission, the algorithm is utilized to realize the real-time optimization by coordination between nodes. The simulation results show that the proposed protocol can realize the QoS optimization for multisink wireless sensor networks, and its performance is better than the routing protocol of minimum hop numbers. [ABSTRACT FROM AUTHOR]

Wireless sensor networks (WSNs) can be used in a wide range of environments. Due to the inherent characteristics of wireless communications, WSNs are more vulnerable to be attacked than conventional networks. Authentication and data confidentiality are critical in these settings. It is necessary to design a useful key management scheme for WSNs. In this paper, we propose a novel key management scheme called MAKM (modular arithmetic based key management). The proposed MAKM scheme is based on the congruence property of modular arithmetic. Each member sensor node only needs to store a key seed. This key seed is used to compute a unique shared key with its cluster head and a group key shared with other nodes in the same cluster. Thus, MAKM minimizes the key storage space. Furthermore, sensor nodes in the network can update their key seeds very quickly. Performance evaluation and simulation results show that the proposed MAKM scheme outperforms other key-pool-based schemes in key storage space and resilience against nodes capture. MAKM scheme can also reduce time delay and energy consumption of key establishment in large-scale WSNs. [ABSTRACT FROM AUTHOR]

Maximizing network lifetime is an important objective for the target-coverage problem. With practicable manufacture and cost reduction, directional sensor has been widely used in wireless sensor networks to save energy. In this paper, we address the target Q-coverage (TQC) problem to prolong the network lifetime with bounded service delay constraint in directional sensor networks. We propose a protocol to find a collection of coverage sets that satisfy the coverage quality requirement and the bounded service delay constraint, where the target in each coverage set may not be served continuously but can be served with tolerant service delay. By steering some sensors' directional antennas, our protocol could deal with the changes of network topology or monitoring tasks. Simulation results show that the performance of our protocol is close to the upper bound of the optimal solution. [ABSTRACT FROM AUTHOR]

IEEE 802.16j is an amendment to the IEEE 802.16 broadband wireless access standard to enable the operation of multihop relay stations (RSs). It aims to enhance the coverage, per user throughput of IEEE 802.16e. Comparing with a base station (BS), RS does not need a wireline backhaul and has much lower hardware complexity. Moreover, using RSs can significantly reduce the deployment cost of the system. Unfortunately, there are some tradeoffs in the case of multi-hop RSs. Subscriber stations (SSs), located in a long distance, are suffered from the bottleneck of multi-hop, throughput degradation, and increasing of end-to-end delay. This paper proposes a network coding-based relay scheme for multi-hop relay networks, called NC-BR. It allows RSs to combine two wireless backhaul transmissions into one using the network coding technique. This paper also proposes an improved OFDMA frame structure design for the multi-hop relay network. This technique provides higher utilization for the relay zone by reorganizing the RSs transmission sequence. The analysis and simulation results confirm that the proposed scheme can enhance the throughput gain up to 140% and reduce the end-to-end delay by up to 83%. The simulation results also show that the proposed scheme can reduce the jitter by up to 58%. [ABSTRACT FROM AUTHOR]

Recently, underwater wireless sensor networks (UWSNs) have attracted much research attention from both academia and industry, in order to explore the vast underwater environment. UWSNs have peculiar characteristics; that is, they have large propagation delay, high error rate, low bandwidth, and limited energy. Therefore, designing network/routing protocols for UWSNs is very challenging. Also, in UWSNs, improving the energy efficiency is one of the most important issues since the replacement of the batteries of underwater sensor nodes is very expensive due to the unpleasant underwater environment. In this paper, we therefore propose an energy efficient routing protocol, named (energy-efficient depth-based routing protocol) EEDBR for UWSNs. EEDBR utilizes the depth of sensor nodes for forwarding data packets. Furthermore, the residual energy of sensor nodes is also taken into account in order to improve the network lifetime. Based on the comprehensive simulation using NS2, we observe that EEDBR contributes to the performance improvements in terms of the network lifetime, energy consumption, and end-to-end delay. A previous version of this paper was accepted in AST-2011 conference. [ABSTRACT FROM AUTHOR]

In a microgrid as an energy infrastructure, the vulnerability against jamming attacks is fatal. Thus, the ability to deal with jamming attacks and maintain an acceptable level of service degradation in presence of the attacks is needed. To solve the problem, we propose a traffic rerouting scheme in wireless communication infrastructure for islanded microgrid. We determine disjoint multiple paths as candidates of a detour path and then select the detour path among the candidates in order to reduce the effect of jamming attack and distribute traffic flows on different detour paths. Through performance comparison, we show that our scheme outperforms a conventional scheme in terms of packet delivery ratio and end-to-end delay. [ABSTRACT FROM AUTHOR]

Performance analysis is crucial for designing predictable and cost-efficient sensor networks. Based on the network calculus theory, we propose a flow-based traffic splitting strategy and its analytical method for worst-case performance analysis on cluster-mesh sensor networks. The traffic splitting strategy can be used to alleviate the problem of uneven network traffic load. The analytical method is able to derive close-form formulas for the worst-case performance in terms of the end-to-end least upper delay bounds for individual flows, the least upper backlog bounds, and power consumptions for individual nodes. Numerical results and simulations are conducted to show benefits of the splitting strategy as well as validate the analytical method. The numerical results show that the splitting strategy enables much better balance on network traffic load and power consumption. Moreover, the simulation results verify that the theoretic bounds are fairly tight. [ABSTRACT FROM AUTHOR]