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In this paper, the outage performance of wireless networks with unstructured topologies is investigated. The network reliability perspective of graph theory is used to obtain the network outage polynomial of generalized wireless networks for both uncorrelated and correlated wireless channels. A relationship is established between the max-flow min-cut theorem and key communication performance indicators. The diversity order is equal to the size of the minimum cut-set between source and destination, and the coding gain is the number of cut-sets with size equal to the minimum cut. An ergodic capacity analysis of arbitrary network topologies based on the network outage polynomial is also presented. Numerical results are used to illustrate the technical definitions and verify the derivations. [ABSTRACT FROM AUTHOR]

Wireless Ad Hoc Networks (WANETs) are predicted to be prevalent networks in coming future because of their infrastructure-less characteristics that result in self-organization, self-healing, and self-configuration of such networks. Routing means the process of selecting a path along which data can be transferred from source to destination that plays a significant role in the performance of ad hoc networks. There are many routing protocols developed for wireless ad hoc networks. One of such protocols, developed by C. E. Perkins, is Ad Hoc On-demand Distance Vector (AODV) routing protocol, which is a reactive routing protocol, AODV is used to establish route(s) between source node(s) and destination node(s) as and when routes are required. Performance of AODV routing protocol depends heavily on choice of values of a set of predefined attributes. One of such attributes of AODV is Node Traversal Time (NTT) which is supposed to play significant role in establishing route(s) between source node(s) and destination node(s). In this paper, we have investigated the performance of AODV in a linear wireless ad hoc network using different values of NTT using as well as without using Hello messages. The performance of the network has been measured using several metrics like Route Error Overhead, Routing Overhead, Normalized Routing Load, Average Hop Count, Total Number of Received Data Packets, Packet Delivery Ratio, Average End-to-End Delay and Throughput. It is observed that choice of value of NTT has a significant effect on establishment of route(s) between source node(s) and destination node(s) that eventually affects the performance of the linear wireless ad hoc network under consideration. The insights gained through this work could be useful in analysis of more realistic and complex networks. [ABSTRACT FROM AUTHOR]

In this paper, we propose a joint transceiver beamforming design method for hybrid full-duplex (FD) and half-duplex (HD) ad-hoc networks to cancel co-channel interference, thereby to improve system spectral efficiency. To characterize network performances, we derive a general expression of transmission capacity upper bound (TC-UB) plus its two compact versions by using a stochastic geometry model. Due to the proposed beamforming design and hybrid-duplex consideration, the exact TC and conventional methods to obtain TC-UBs are not applicable. This motivates us to exploit the UB of the largest eigenvalue of desired signals, Alzer’s inequality for the incomplete gamma function, and dominating interference region to formulate one general TC-UB and two of its compact versions. The numerical results show that the proposed beamforming method outperforms the existing beamforming strategies in terms of exact TC, especially when the number of transmit antennas is larger than the number of receiver antennas per node pair. In addition, the derived general TC-UB can provide relatively close TC performance as the exact ones, and its two compact versions can at least give order-wise TC performance. Moreover, we find the break-even points, where FD outperforms HD with different system configurations. [ABSTRACT FROM AUTHOR]

Previous work has demonstrated the feasibility of Bluetooth Low Energy (BLE) as an alternative technology for data transfers in inter-vehicular communication (IVC) scenarios. Bluetooth 5.x core specifications enhance the trade-off between energy requirements, communication range and flexibility. In this paper, we aim to analyse the potential of Bluetooth 5 features for VANET applications, proposing a connectionless communication system. By means of field experiments, we evaluate long range and 2 × speed features, defining a set of communication scenarios. This allows us to test both Bluetooth 5.x range and application throughput. The evaluation includes experiments of V2I communications carried out under real highway traffic conditions. The experiments conducted demonstrate that communication ranges up to 300 m may be achieved depending on the communications scenario. The results also show how throughput degrades as the distance between devices increases. The results obtained are used to discuss future work, aimed at deeper analysing Bluetooth 5 features for VANET applications, completing the development of our prototype and evaluating VANET connectionless communications with the features included in the latest Bluetooth 5.2 specification. [ABSTRACT FROM AUTHOR]

Recently, unmanned aerial vehicles (UAVs) have been utilized to extend the coverage and capacity of terrestrial wireless networks. In such a UAV-aided wireless network, we can exploit the more favorable line-of-sight (LOS) propagation in the UAV-user wireless link to achieve better coverage and higher capacity. Furthermore, the flexible deployment of UAVs makes them ideal for catering to ad hoc demand. Due to the lack of fixed-line backhaul, UAVs act like relays with wireless backhaul links in UAV-aided wireless networks. Unlike the conventional relays in terrestrial wireless networks, the positions of UAV-Rs can be optimized to maximize the system performance. Although the optimal UAV positioning problem has been studied under simple LOS/probabilistic channel models, the joint optimization of UAV positions, user association, and wireless backhaul capacity allocation remains unsolved under realistic channel models, which will be addressed in this paper. The joint optimization problem is a challenging mixed non-convex and combinatorial problem. Combining the block coordinate descent and successive convex approximation (SCA) methods, we propose a sparse parallel block SCA algorithm, which can find a near-optimal solution by exploiting the structures of the propagation model. The simulations verify the significant gain of the proposed solution over existing solutions. [ABSTRACT FROM AUTHOR]

The problem of routing security in vehicular ad hoc networks has become a major concern for researchers. Compared with cryptography-based solutions, trust-based solutions are considered to be more acceptable as a promising approach, which mainly define two operations: trust computing and security application. In this paper we first study trust properties and construct a novel trust inference model, where two trust attributes named subjective trust and recommendation trust, are selected to quantify the trust level of a specific vehicle. The SCGM(1,1)-weighted Markov prediction algorithm based on fluctuation recognition is utilized to calculate the subjective trust accurately, meanwhile a new evaluation method of recommendation credibility based on the feedback mechanism is introduced for the calculation of recommendation trust. We subsequently exploit the advantages of mesh structure and design a light-weight trust-aware multicast routing protocol (i.e., LTMRP), which can establish secure and reliable communication paths by selecting trusted relay vehicles. To further improve the routing efficiency, two mechanisms including forwarding nodes reuse mechanism and trust-aware route handoff mechanism are proposed. Simulation verification and comparison of the relevant trust models and trust-based protocols are accomplished by three simulation platforms (i.e., Netlogo, SUMO, and NS-2).The convincing results show that our trust model obtains strong resistibility to multiple malicious attacks. Moreover, examined in four routing metrics, the experimental results indicate that LTMRP performs better than the other relevant protocols. [ABSTRACT FROM AUTHOR]

Applications of the Internet of Things (IoT) require validation considering many types of environments before their actual implementation. Generally, the validation of these systems may be conducted by software through the use of emulators and simulators. However, the validation by software has limitations that can prevent a realistic approximation of the system behavior in real environments. For this reason, the scientific community has dedicated a great deal of effort to develop experimental testbeds. In light of this, we present a review of the state-of-the-art related to the testbeds for wireless sensor networks and IoT applications. In addition, we carried out a comparative analysis considering the technical specifications of the selected testbeds and highlighted their capabilities. Finally, we conclude with a discussion of the advantages and limitations of the testbeds with regard to the key requirements needed for IoT experimentation. [ABSTRACT FROM AUTHOR]

As network resources are shared between many users, resource management must be a key part of any communication system as it is needed to provide seamless communication and to ensure that applications and servers receive their required Quality-of-Service. However, mobile environments also need to consider handover issues. Furthermore, in a highly mobile environment, traditional reactive approaches to handover are inadequate and thus proactive techniques have been investigated. Recent research in proactive handover techniques defined two key parameters: Time Before Handover (TBH) and Network Dwell Time (NDT) for a mobile node in any given networking topology. Using this approach, it is possible to enhance resource management in common networks using probabilistic mechanisms because it is possible to express contention for resources in terms of No Contention, Partial Contention, and Full Contention. This proactive approach is further enhanced by the use of a contention queue to detect contention between incoming requests and those waiting for service. This paper therefore presents a new methodology to support proactive resource allocation for future networks such as Vehicular Ad-Hoc Networks. The proposed approach has been applied to a vehicular testbed and results are presented that show that this approach can improve overall network performance in mobile heterogeneous environments. [ABSTRACT FROM AUTHOR]

This paper studies the beneficial combination of wireless power transfer and millimeter-wave (mmWave) communications in wireless sensor networks. In particular, an mmWave wireless powered sensor network is considered, where the access point (AP) employs beamforming techniques to transfer energy to the sensors of a selected sector of the cell. The served sensors harvest and store energy from the received signal, and use it to power their uplink transmissions. We consider a random energy beamforming scheme but also propose several intelligent schemes that steer the beam to specific areas of the cell by considering the sensors’ locations. This setup is investigated from a large-scale point-of-view where spatial randomness is considered with the aid of Poisson point processes. The performance of the network is described in terms of the energy outage probability and the beam outage probability. We show that, depending on the scenario, each of the considered energy beamforming schemes can provide significant gains to the network’s performance. Finally, we study an event monitoring application of our theoretical framework, where the active sensors observe a random event in the network and the AP attempts to estimate it based on the received information; this scenario is evaluated in terms of the estimation’s mean squared error. [ABSTRACT FROM AUTHOR]

Probabilistic flooding is commonly considered in vehicular ad-hoc networks (VANETs) to alleviate the celebrated broadcast storm problem. Heuristics and simulations have so far proved to be an efficient way with which to design probabilistic information dissemination solutions with demonstrated effectiveness. Supplementing with mathematical analysis for both design and evaluation is expected to generalize the results, and increase the confidence in the proposed solutions. So far, this has been limited due to the difficulties associated with the underlying stochastic dependencies. In this paper, we introduce simple models of single and multiple lane roads to design effective probabilistic flooding schemes for VANETs. The proposed analytical framework offers a novel and generic tool which can cover any number of lanes, vehicle transmission range, and density. We derive difference equations whose solutions yield the probability of all vehicles receiving the emergency warning message as a function of the rebroadcast probability, the number of neighbors of each vehicle, and the dissemination distance. The models are validated using simulations, realistically representing both the traffic and networking aspects, and are used as a baseline to design two schemes for information dissemination which employ probabilistic flooding. The one attempts direct calculation of the required parameters whereas the other adaptively regulates the rebroadcast probability based on the vehicle speed. The schemes are evaluated using simulations and are found to achieve significant performance improvements compared to blind flooding with respect to the achieved reachability, end-to-end delay, and number of rebroadcasts, comparable to the performance achieved by optimal flooding, obtained via brute force. [ABSTRACT FROM AUTHOR]

How to achieve reliable routing has always been a major issue in the design of communication networks, among which mobile ad hoc networks (MANETs) possess the most adversarial networking environment due to the absence of fixed infrastructure, the nature of open transmission media and the dynamic network topology. These characteristics also make the design of routing protocols in MANETs become even more challenging. In this paper, we propose an evolutionary self-cooperative trust (ESCT) scheme that imitates human cognitive process and relies on trust-level information to prevent various routing disruption attacks. In this scheme, mobile nodes will exchange trust information and analyze received trust information based on their own cognitive judgment. Eventually, each node dynamically evolves its cognition to exclude malicious entities. The most attractive feature of ESCT is that they cannot compromise the system even if the internal attackers know how the security mechanism works. In this paper, we evaluate the performance of ESCT scheme under various routing disruption attack situations. Simulation results affirm that ESCT scheme promotes network scalability and ensures the routing effectiveness in the presence of routing disruption attackers in MANETs. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the request routing delay of opportunistic routing for cache-enabled wireless networks considering uncorrelated and temporally correlated wireless channels. We model wireless channel variation at different time scales via two approaches: an abstract modeling approach where we model the variation considering Rayleigh fading and shadowing channel models and an empirical approach where the variation is modeled directly using signal strength measurements. We develop Markovian models to analyze the performance of opportunistic forwarding, leverage the wireless channel models to determine the packet transmission success probabilities and then utilize them to obtain the request routing delay. We first perform numerical experiments and simulations considering Rayleigh fading and shadowing channel models and then conduct a trace-based evaluation using signal strength measurements collected over a wireless sensor network testbed. Our experiments demonstrate the validity and effectiveness of our Markovian model in determining the request routing delay in real-world settings. Our work takes a step forward in providing network operators a tool for analyzing network performance before deploying their networks. [ABSTRACT FROM AUTHOR]

In this paper, we consider a network reconstruction problem using unmanned aerial vehicles (UAVs) where stationary ad hoc networks are severely damaged in a post-disaster scenario. The main objective of this paper is to repair the network by supplementing aerial wireless links into the isolated ground network using UAVs. Our scheme performs network probing from the air and finds out crucial spots where both local and global routing performance can significantly be recovered if deployed. First, we propose a novel distributed coverage path planning algorithms with independent and computationally lightweight navigation based on adaptivezigzagpatterns. Second, we present route topology discovery schemes that capture both local andnon-local network connectivity by extracting inherent route skeletons via stitching partial local paths obtained from the simple packet probing by UAVs. Finally, we find the optimal UAV relay deployment positions that can improve network-wide data delivery most effectively based on three novel approaches of an optimization technique, an iterative heuristic algorithm, and a topology partitioning ofstrongly connected component. Simulation results demonstrate that our distributed traversing algorithms reduce the complete coverage time, the travel distance, and the duplicate coverage compared to other counterpart algorithms. Our deployment algorithms recover severely impaired routes, incurring reasonable computational overhead. [ABSTRACT FROM AUTHOR]

This paper studies finding the secure path according to the secrecy connectivity probability (SCP) in the multihop ad hoc networks in the presence of inhomogeneous eavesdropper clusters. We consider both random and fixed eavesdropper clusters, where the former case assumes that there is no knowledge of the locations of the clusters and the latter case assumes that the locations of the clusters can be estimated accurately. First, we derive the end-to-end SCP to characterize the secrecy performance of a given path in a general multihop wireless network with half-duplex randomize-and-forward relaying. Then, we consider a full-duplex scheme at the legitimate receiver, which receives the useful information while broadcasting a jamming signal to the potential eavesdroppers to further enhance the secrecy connectivity. Then, a novel secure routing algorithm that can provide the maximum SCP for any legitimate transmitter/receiver pair in a distributed manner is proposed. The theoretical analysis is verified by Monte Carlo simulation results. The results show that our secure routing algorithm provides similar results compared to an exhaustive search. For the random eavesdropper cluster case, the optimal route is independent of the knowledge of the cluster, which is the same as the homogeneous eavesdropper case. However, for the case where eavesdropper clusters are fixed and their locations are knowna priori, the optimal path selection depends on the radii and locations of the eavesdropper clusters and the average number of eavesdroppers in each cluster. [ABSTRACT FROM AUTHOR]

This paper develops a stochastic geometry-based approach for the modeling and analysis of single- and multi-cluster wireless networks. We first define finite homogeneous Poisson point processes to model the number and locations of the transmitters in a confined region as a single-cluster wireless network. We study the coverage probability for a reference receiver for two strategies; closest-selection, where the receiver is served by the closest transmitter among all transmitters, and uniform-selection, where the serving transmitter is selected randomly with uniform distribution. Second, using Matern cluster processes, we extend our model and analysis to multi-cluster wireless networks. Here, two types of receivers are modeled, namely, closed- and open-access receivers. Closed-access receivers are distributed around the cluster centers of the transmitters according to a symmetric normal distribution and can be served only by the transmitters of their corresponding clusters. Open-access receivers, on the other hand, are placed independently of the transmitters and can be served by all transmitters. In all cases, the link distance distribution and the Laplace transform (LT) of the interference are derived. We also derive closed-form lower bounds on the LT of the interference for single-cluster wireless networks. The impact of different parameters on the performance is also investigated. [ABSTRACT FROM AUTHOR]

In this paper, we consider the problem of joint secure routing and transmit power optimization for a multi-hop ad-hoc network under the existence of randomly distributed eavesdroppers following a Poisson point process. Secrecy messages are delivered from a source to a destination through a multi-hop route connected by multiple legitimate relays in the network. Our goal is to minimize the end-to-end connection outage probability under the constraint of a secrecy outage probability threshold, by optimizing the routing path and the transmit power of each hop jointly. We show that the globally optimal solution could be obtained by a two-step procedure where the optimal transmit power has a closed-form and the optimal routing path can be found by Dijkstra’s algorithm. Then a friendly jammer with multiple antennas is applied to enhance the secrecy performance further, and the optimal transmit power of the jammer and each hop of the selected route is investigated. This problem can be solved optimally via an iterative outer polyblock approximation with 1-D search algorithm. Furthermore, suboptimal transmit powers can be derived using the successive convex approximation method with a lower complexity. Simulation results show the performance improvement of the proposed algorithms for both non-jamming and jamming scenarios, and also reveal a non-trivial tradeoff between the numbers of hops and the transmit power of each hop for secure routing. [ABSTRACT FROM AUTHOR]

Estimating communication latency is a challenging task in the applications of industrial Internet of things (IIoT). Mobile convergecast, as a many-to-one communication pattern, has been recently explored in mobile sensor networks for IIoT, where sensor nodes are usually in mobile status, and report the sensed data regularly or randomly to one or more stationary sinks through the multihop routing path. As convergecast becomes increasingly relevant for industrial sensing and monitoring, a critical part of empowering information aggregation is to maintain consistent transmission. Path duration is one important component of end-to-end delay for communications along the path. In this paper, a probabilistic model for mobile convergecast has been proposed and evaluated to capture path duration times, by considering parameters including network models, sensor network scope, and mobility patterns of network elements. Through experiments, it has been verified that the proposed model can provide a feasible analysis of end-to-end delays in industrial networks implementing convergecast. [ABSTRACT FROM AUTHOR]

Cache-enabled wireless networks have gained increasing popularity in recent years for facilitating the delivery of content. Most existing works assumed that the network is static without the change of users and content, which is not the case in the real world. In this paper, we study the content delivery in cache-enabled wireless networks, where the network evolves in terms of users and content. We adopt the affiliation network model to reveal the network evolution process, where new users and content are added into the network randomly and connected with existing nodes via the preferential attachment. Users with strong social relations tend to request the same content objects, thus content popularity is sharply concentrated. Therefore, caching technique is more effective. To maximize the content delivery rate, we formulate the optimization problem of caching replication jointly with routing strategy. We show that network evolution can greatly improve the content delivery rate. In particular, when per-user cache capacity is in the order of $\Theta (1)$ , per-user delivery rate can achieve constant, i.e., the network can scale. Finally, theoretical results are validated based on a real-world data set from Facebook. [ABSTRACT FROM AUTHOR]

Network location is one of the critical issues and a challenge in wireless sensor and ad hoc networks, in particular when networks are sparse. However, even in highly sparse networks, there exist well-connected subgraphs while the distribution of the networks is random. This paper introduces weighted component stitching (WCS) to find redundantly rigid components with high redundant ratios, which can be used to generate reliable local realization. Finding and ranking the redundantly rigid components is an NP-hard problem (a reduction from maximum quasi-clique). Here, we introduce a series of theorems and algorithms to carry out WCS efficiently. More precisely, we prove that each graph has a determinant number of redundantly rigid components, each redundantly rigid component is covered by a set of basic redundant components (BRCs), and each BRC contains one redundant edge. We apply constraints to merge the BRCs to form components with higher redundancy ratio and develop a greedy algorithm to merge BRCs to form locally mostly redundant components (LMRCs). Finally, we give the approximation ratio. The local coordinates of nodes are calculated by optimization in each LMRC and are synchronized with weights to produce the global coordinates of nodes in the network to overcome the sparseness of subgraphs. Extensive experiments demonstrate significant improvements in accuracy (45%–64%) using our WCS method over the state-of-the-art algorithms under various settings of network sparseness and ranging noises. [ABSTRACT FROM AUTHOR]

This paper examines a new application of the well-known ARP spoofing (or ARP cache poisoning) attack. Traditionally, ARP spoofing has been applied in local area networks to allow an attacker to achieve a man-in-the-middle position against target hosts, or to implement a denial-of-service by routing messages to non-existent hardware addresses. In this paper, we introduce a variant of ARP spoofing unique to multi-hop ad hoc networks in which routing loops are created among target wireless hosts. The routing loops not only results in a denial-of-service against the targeted hosts, but creates a resource consumption attack, where the targets waste power and occupy the channel, precluding its use by legitimate traffic. The paper identifies the network topology pre-conditions under which routing loops are possible, and discusses how ARP spoof messages can be used to create routing loops of arbitrary size. We show experimental results of an implementation and provide suggestions as to how to prevent, detect, or mitigate the attack. [ABSTRACT FROM AUTHOR]

Emergence of various types of wireless applications has brought about fast growing and diversified traffic in cellular networks. To gain a comprehensive understanding of the influences caused by the differentiated and dynamic traffic is vital for the design of the next-generation wireless networks. In this paper, we develop a mathematical framework for meta-distribution analysis by utilizing queueing theory and stochastic geometry to capture the spatial (geographical location) and temporal randomness (queue status) of traffic. We derive the ${k}$ -th moment of the conditional successful transmission probability (STP) and the closed-form expressions of the meta distribution for the cell-center users (CCUs) and the cell-edge users (CEUs), respectively. The results are further extended to obtain the analytical expression of the meta distribution by taking the temporal random arrival of traffic into consideration. Moreover, the mean local delays for the CCUs and CEUs are derived. Finally, the impact of key network parameters on the meta distribution and the corresponding mean local delay is investigated. [ABSTRACT FROM AUTHOR]

Shannon showed that to achieve perfect secrecy in point-to-point communication, the message rate cannot exceed the shared secret key rate giving rise to the simple one-time pad encryption scheme. In this paper, we extend this work from point-to-point to networks. We consider a connected network with pairwise communication between the nodes and assume that each node is provided with a certain amount of secret bits before communication commences. An eavesdropper with unlimited computing power has access to all communication and can hack a subset of the nodes not known to the rest of the nodes. We investigate the limits on information-theoretic secure communication with end-to-end encryption for this network. We establish a tradeoff between the secure channel rate (for a node pair) and the secure network rate (sum over all node pair rates) and show that information-theoretic secrecy can be achieved asymptotically if and only if the sum rate of any subset of unhacked channels does not exceed the shared unhacked-secret-bit rate of these channels. We also propose a practical scheme that achieves a good balance of network and channel rates with information-theoretic secrecy guarantee. This work has a wide range of potential applications for which strong secrecy is desired, such as cyber-physical systems, distributed-control systems, and ad-hoc networks. [ABSTRACT FROM AUTHOR]

This paper considers the time evolution of a queue that is embedded in a Poisson point process of moving wireless interferers. The queue is driven by an external arrival process and is subject to a time-varying service process that is a function of the SINR that it sees. Static configurations of interferers result in an infinite queue workload with positive probability. In contrast, a generic stability condition is established for the queue in the case where interferers possess any non-zero mobility that results in displacements that are both independent across interferers and oblivious to interferer positions. The proof leverages the mixing property of the Poisson point process. The effect of an increase in mobility on queuing metrics is also studied. Convex ordering tools are used to establish that faster moving interferers result in a queue workload that is smaller for the increasing-convex stochastic order. As a corollary, mean workload and mean delay decrease as network mobility increases. This stochastic ordering as a function of mobility is explained by establishing positive correlations between SINR level-crossing events at different time points, and by determining the autocorrelation function for interference and observing that it decreases with increasing mobility. System behaviour is empirically analyzed using discrete-event simulation and the performance of various mobility models is evaluated using heavy-traffic approximations. [ABSTRACT FROM AUTHOR]

Routing is a fundamental problem and has been extensively studied in various networks. However, in highly dynamic networks (e.g., wireless ad hoc networks), nodes have limited transmission opportunities due to high mobility, noise and interference, where traditional routing is often not the best approach. Opportunistic routing (OR), on the other hand, can effectively minimize the routing cost (e.g., the number of hops) and improve the success of routing by utilizing link metrics. However, the link metrics are usually unknown in advance and changing. In this paper, we design an adaptive algorithm called Thompson sampling-based opportunistic routing (TSOR) motivated by the distributed Bellman-Ford algorithms. TSOR is able to learn the link metrics and route packets simultaneously to reduce the overall cost. Theoretically, we show a lower bound and an upper bound of the cumulative regret (i.e., performance gap) between TSOR and the optimal routing algorithm that knows all link metrics in advance. The regret increases sublinearly with respect to the number of packets, and has a lower order in terms of the network size than the best-known results. Furthermore, we compare TSOR with the state-of-the-art algorithms, and the evaluation results show that TSOR has a lower regret and a faster convergence rate to the optimal policy than the state-of-the-art algorithms. [ABSTRACT FROM AUTHOR]

The object of research is the military radio communication system. Effective operation of routing protocols is possible only if there is reliable information about the network topology for network nodes, given that the mobility of individual nodes is insignificant in special purpose wireless networks. Because nodes in the network demonstrate the mobility property of the node groups. This paper solves the problem of the analysis (decomposition) of methods of protocols efficiency increase of dynamic routing in telecommunication networks with a possibility to self-organization. In the course of the research, the authors used the main provisions of the queuing theory, the theory of automation, the theory of complex technical systems and general scientific methods of cognition, namely analysis and synthesis. This research analyzes various methods to increase the efficiency of dynamic routing protocols. Energy efficiency methods focus on three main components in energy management: battery management, transmission energy management and system energy management methods. Reliable multicast has become indispensable for the successful deployment of special purpose wireless networks, such as in tactical military operations and emergency operations. The results of the research will be useful in: – development of new routing algorithms; – substantiation of recommendations for improving the efficiency of the route selection process in networks with the possibility of self-organization; – analysis of the electronic situation during hostilities (operations); – while creating promising technologies to increase the efficiency of mobile radio networks. Areas of further research will focus on the development of a methodology for the operational management of interference protection of intelligent military radio communication systems. [ABSTRACT FROM AUTHOR]

This paper presents $\mathit {wChain}$ , a blockchain protocol specifically designed for multihop wireless networks that deeply integrates wireless communication properties and blockchain technologies under the realistic SINR model. We adopt a hierarchical spanner as the communication backbone to address medium contention and achieve fast data aggregation within $O(\log N\log \Gamma)$ slots where $N$ is the network size and $\Gamma $ refers to the ratio of the maximum distance to the minimum distance between any two nodes. Besides, $\mathit {wChain}$ employs data aggregation and reaggregation as well as node recovery mechanisms to ensure efficiency, fault tolerance, persistence, and liveness. The worst-case runtime of $\mathit {wChain}$ is upper bounded by $O(f\log N\log \Gamma)$ , where $f=\lfloor \frac {N}{2} \rfloor $ is the upper bound of the number of faulty nodes. To validate our design, we conduct both theoretical analysis and simulation studies. The results not only demonstrate the nice properties of $\mathit {wChain}$ , but also point to a large new space for the exploration of blockchain protocols in wireless networks. [ABSTRACT FROM AUTHOR]

To cope with an exponentially increasing demand on mobile data traffic in cellular networks, high-capacity WiFi and device-to-device networks can be exploited as a complementary means to offload and reduce the traffic load of cellular networks. This paper proposes a novel cooperative content dissemination strategy for a heterogeneous network consisting of different types of devices, such as WiFi access points (APs), smartphones, and intelligent vehicles. The proposed strategy offloads a significant proportion of data traffic from cellular networks to WiFi or device-to-device networks using ad hoc connections that opportunistically emerge when mobile devices move and meet one another. The strategy is particularly suited for dissemination of delay-tolerant content. Detailed analysis is provided for the content dissemination process in heterogeneous mobile networks adopting the proposed strategy. On this basis, the optimal parameter settings for the content dissemination strategy are discussed. Simulation and numerical results show that the proposed strategy significantly reduces the amount of data traffic for cellular networks while guaranteeing the successful delivery of content. [ABSTRACT FROM AUTHOR]

In this paper, an intrusion detection system (IDS) for vehicular ad hoc networks (VANETs) is proposed and evaluated. The IDS is evaluated by simulation in the presence of rogue nodes (RNs) that can launch different attacks. The proposed IDS is capable of detecting a false information attack using statistical techniques effectively and can also detect other types of attacks. First, the theory and implementation of the VANET model that is used to train the IDS is discussed. Then, an extensive simulation and analysis of our model under different traffic conditions is conducted to identify the effects of these parameters in VANETs. In addition, the extensive data gathered in the simulations are presented using graphical and statistical techniques. Moreover, RNs are introduced in the network, and an algorithm is presented to detect these RNs. Finally, we evaluate our system and observe that the proposed application-layer IDS based on a cooperative information exchange mechanism is better for dynamic and fast-moving networks such as VANETs, as compared with other techniques available. [ABSTRACT FROM AUTHOR]

In this paper, we study the asymptotic throughput capacity of a static multi-channel multi-interface infrastructure wireless mesh network (InfWMN) wherein each infrastructure node has m interfaces and c channels of unequal bandwidth are available. First, an upper bound on the InfWMN per-user capacity is established. Then, the feasible lower bound is derived by construction. We prove that both lower and upper bounds are tight. We limit our analysis for more practical case of \mathrmm \le \mathrmc . However, for the asymptotic upper bound, our analysis can be used for the general case in which there is no constraint on m and c. Our study shows that in such a network with Nc randomly distributed mesh clients, Nr regularly placed mesh routers, and Ng gateways, the asymptotic per-client throughput capacity has different bounds, which depend on the ratio between the total available bandwidth for the network and the sum of m first greatest data rates of c available channels, i.e., \sum \limits\mathrm{j = 1}^\mathrm{C} \mathrm{w}_\mathrm{j} / \sum \limits\mathrm{j = 1}^\mathrm{m} \mathrm{w}_\mathrm{j} . The results of this paper are more general compared to the existing published researches. In addition, in the case that \mathrmw_\mathrmi = \mathrmW/\mathrmc \forall \mathrmi,\mathrm1 \le \mathrmi \le \mathrmc , our results reduce to the previously reported studies. This implies that our study is comprehensive compared to the formerly published researches. [ABSTRACT FROM AUTHOR]

Despite extensive efforts on exploring the asymptotic capacity bounds for mobile ad hoc networks (MANETs), the general exact capacity study of such networks remains a challenge. As one step to go further in this direction, this paper considers two classes of Aloha MANETs (A-MANETs) \mathcalNA and \mathcalNC that adopt an aggressive traffic-independent Aloha and the conventional traffic-dependent Aloha, respectively. We first define a notation of successful transmission probability (STP) in \mathcalNA, and apply queuing theory analysis to derive a general formula for the capacity evaluation of \mathcalNA. We also prove that \mathcalNC actually leads to the same throughput capacity as \mathcalNA, indicating that the throughput capacity of \mathcalNC can be evaluated based on the STP of \mathcalNA as well. With the help of the capacity formula and stochastic geometry analysis on STP, we then derive closed-form expressions for the throughput capacity of an infinite A-MANET under the nearest neighbor/receiver transmission policies. Our further analysis reveals that although it is highly cumbersome to determine the exact throughput capacity expression for a finite A-MANET, it is possible to have an efficient and closed-form approximation to its throughput capacity. Finally, we explore the capacity maximization and provide extensive simulation/numerical results. [ABSTRACT FROM AUTHOR]

This paper studies the throughput capacity of wireless networks with social characteristics. We propose a simple model to reflect both the social relations between nodes and power-law node degree distribution, and then examine their impact on capacity. We show the fact that two features above lead to traffic locality and improve capacity. Moreover, multicasting may be employed to further enhance performance when information is desired to be published from the source to all its contacts, of which the number follows power-law distribution. In addition, we propose the corresponding capacity-achieving communication schemes, which optimally exploit the underlying structure. Our study is an attempt to understand how social relations may impact on network capacity from a theoretical perspective, and provides fundamental insight on the design and analysis of real wireless networks. [ABSTRACT FROM PUBLISHER]

In this paper, we study the effects of social interactions among nodes on the capacity of wireless networks. We consider three scenarios. In the first scenario, the size of the social group for all nodes is fixed while the frequency of communication within members of a social group follows power law distribution. In the second scenario, scale-free networks are studied where the size of the social group differs from node to node, and the destination in each group is selected uniformly among the members of that group. Further investigation in the second scenario reveals that traditional transport capacity definition provides misleading conclusions for such network models. We show that nodes with different social status impact the capacity differently. By separating nodes with different social status and allocating separate bandwidth to them, it is shown that majority of nodes scale in this network. In the third scenario, both the size of the social groups and the destination in each group are selected according to power law distributions. Our simulation results corroborate the analytical results. Further, we observe consistently that social interaction improves the capacity of wireless networks, which implies that the Gupta–Kumar results were pessimistic for practical networks. [ABSTRACT FROM PUBLISHER]

Verification of theoretical analysis is a vital step in the development of an application or a protocol for wireless networks. Most proposals are evaluated through mathematical analysis followed by either simulation or experimental validation campaigns. In this article, we analyze a large set of statistics in articles published (674 papers in total) in the top representative ad hoc and wireless sensor networks related conferences (i.e., ACM/ IEEE IPSN, ACM MobiCom, ACM MobiHoc, and ACM SenSys) during the period 2008?2013. We focus on the evaluation methodologies provided by researchers. More specifically, our goal is to explore the role of simulators and testbeds in the theoretical analysis of a model throughout the protocol development procedure. We show that there is a tendency for more and more researchers to rely on custom or open testbeds in order to evaluate the performance of their proposals. Simulators indeed fail to reproduce actual environmental conditions of deployed systems. Experimentation with real hardware allows our research community to mind the gaps between simulation and real deployment. Still, as the experimental apFproach through custom testbeds results in a low reproducibility level (i.e., 16.5 percent), we investigate to what extent such performance evaluation methods will be able to bridge those gaps. We finally discuss experimental testbeds and their potential to replace simulators as the cornerstone of performance evaluation procedures. [ABSTRACT FROM PUBLISHER]

This paper studies the delay constrained multicast capacity of large-scale mobile ad hoc networks (MANETs). We consider a MANET that consists of ns multicast sessions. Each multicast session has one source and p destinations. Each source sends identical information to the p destinations in its multicast session, and the information is required to be delivered to all the p destinations within D .1 We then propose a joint coding/scheduling algorithm achieving a throughput of \Theta (\min \{1,{({D}/{n_{s}})}^{1/2}\}) . Our simulation results suggest that the same scaling law also holds under random walk and random waypoint models.1

Given non-negative functions f(n)$ and g(n)$ : f(n)=O(g(n))$ means there exist positive constants c$ and m$ such that f(n) \leq cg(n)$ for all n\geq m;~f(n)=\Omega (g(n))$ means there exist positive constants c$ and m$ such that f(n)\geq cg(n)$ for all n\geq m;~f(n)=\Theta (g(n)) ; and f(n)=\omega (g(n))$ means that \lim _{n\rightarrow \infty } g(n)/f(n)=0 . [ABSTRACT FROM PUBLISHER]

Summary: A routing protocol for cognitive radio ad hoc networks (CRAHNs), namely, primary user supported routing (PSR) is demonstrated in this research. Unlike existing routing protocols for CRAHN, where routing of cognitive users (CUs) is accomplished within CUs, in this proposed protocol, some of the primary users (PUs) support CUs to communicate, by forwarding CU packets. This service provided by PU is of voluntary nature. However, such assistance shall be provided by the PUs, only when they are idle, thereby, preserving the principles of cognitive radio networks (CRNs), which indicates that the operation of PU should not be disturbed by the CU activities. The proposed work is compared with cognitive ad hoc on‐demand distance vector (CAODV) protocol. The performance parameters considered are routing overhead, rate of loss of packets, and e2e packet delay. PSR outperforms CAODV in all these performance parameters. There has been on average 26.25% improvement in routing overhead, 34.12% decrease in loss, and 27.01% improvement in e2e delivery in the proposed PSR. [ABSTRACT FROM AUTHOR]

Two-Way Ranging (TWR) is a widely used method for distance estimation in asynchronous wireless networks, but the deviation between the clocks can lead to errors in distance estimation. The ultra-wideband (UWB) technology provides the best accuracy in distance estimation, but total emission time is drastically limited by harmonized standards. Localization accuracy, latency and network scalability are key performance metrics in wireless location characterization. This article advances a new sequencing of the localization process, called Double-Beacon Two-Way Ranging (DB-TWR) algorithm, and presents the related time-of-flight (ToF) estimation formula, which is able to compensate for clock error and to reduce the localization period. The Fine Time Measurement (FTM) protocol, specified by the Wireless LAN (WLAN) standard, uses the TWR method and as a result the clock deviation leads to systematic errors in ToF estimation. The paper proposes two additional timestamp s captures and a new ToF computation formula which compensates for clock deviation. The article provides a theoretical analysis and extensive simulations of errors propagation in the ranging process, both as a mean and as an uncertainty, and proves that the designed algorithms cancel the clock offsets entirely. [ABSTRACT FROM AUTHOR]

Vehicular social networks (VSNs) are considered as an emerging class of vehicular ad hoc networks (VANETs) with social attributes. In contrast to the traditional randomly distributed human social networks, vehicles normally only move along fıxed paths. As such, information sharing and forwarding become challenging because of the high speed of vehicles, complicated propagation environment, and quickly changing network topologies. The social characteristics and human behavior features are used to improve the effıciency of information delivery among vehicles in VANETs. In this paper, we propose a dynamic periodic location encounter network (DPLEN) model that considering both time-varying and location-varying characteristics of vehicles. We calculate the line similarity for each encountered pair of vehicles based on the periodic time and location information of the encounter event, and analyze social attributes based on the network model, such as the Community structure, Betweenness Centrality and K-shell. We also use the similarity to design two routing protocols for unicast and multicast patterns. After testing the proposed model on empirically collected datasets of mobility traces, the results show that these two routing protocols are able to greatly improve the efficiency of information forwarding in the VSNs. [ABSTRACT FROM AUTHOR]

Routing protocols are responsible for providing reliable communication between the source and destination nodes. The performance of these protocols in the ad hoc network family is influenced by several factors such as mobility model, traffic load, transmission range, and the number of mobile nodes which represents a great issue. Several simulation studies have explored routing protocol with performance parameters, but few relate to various protocols concerning routing and quality of service (QoS) metrics. This paper presents a simulation-based comparison of proactive, reactive, and multipath routing protocols in mobile adhoc networks (MANETs). Specifically, the performance of AODV, DSDV, and AOMDV protocols are evaluated and analyzed in the presence of varying the number of mobile nodes, pause time, and traffic connection numbers. Moreover, Routing and QoS performance metrics such as normalized routing load, routing packet, packet delivery ratio, packet drop, end-to-end delay, and throughput are measured to conduct a performance comparison between three routing protocols. Simulation results indicate that AODV outperforms the DSDV and AOMDV protocols in most of the metrics. AOMDV is better than DSDV in terms of end-to-end delay. DSDV provides lower throughput performance results. Network topology parameters have a slight impact on AODV performance. [ABSTRACT FROM AUTHOR]

Vehicular Ad hoc Networks (VANETs) that are considered as a subset of Mobile Ad hoc Networks (MANETs) can be applied in the field of transportation especially in Intelligent Transportation Systems (ITS). The routing process in these networks is a challenging task due to rapid topology changes, high vehicle mobility and frequent disconnection of links. Therefore, developing an efficient routing protocol that satisfies restriction of delay and minimum overhead is faced with many difficulties and limitations. Also, the detection of malicious vehicles is a significant task in VANETs. To address these issues, using Unmanned Aerial Vehicles (UAVs) can be helpful to cope with these limitations. In this paper, operation of UAVs in ad hoc mode and their cooperation with vehicles in VANETs are studied to help in the process of routing and detection of malicious vehicles. A routing protocol named VRU is proposed that includes two distinct ways of routing of data: (1) delivering packets of data between vehicles with the help of UAVs using a protocol named VRU_vu, and (2) routing packet of data between UAVs using a protocol named VRU_u. The NS-2.35 simulator under Linux Ubuntu 12.04 is utilized in order to appraise the performance of VRU routing components in an urban scenario. Also, VanetMobiSim generator of mobility and MobiSim are used to produce the motions of vehicles and to produce the motions of UAVs, respectively. The performance analysis displays that VRU protocol can improve the packet delivery ratio by 16% and detection ratio by 7% compared to other reviewed routing protocol. Also, VRU protocol decreases end-to-end delay by an average of 13% and overhead by 40%. [ABSTRACT FROM AUTHOR]

RGBT tracking has attracted increasing attention since RGB and thermal infrared data have strong complementary advantages, which could make trackers all-day and all-weather work. Existing works usually focus on extracting modality-shared or modality-specific information, but the potentials of these two cues are not well explored and exploited in RGBT tracking. In this paper, we propose a novel multi-adapter network to jointly perform modality-shared, modality-specific and instance-aware target representation learning for RGBT tracking. To this end, we design three kinds of adapters within an end-to-end deep learning framework. In specific, we use the modified VGG-M as the generality adapter to extract the modality-shared target representations. To extract the modality-specific features while reducing the computational complexity, we design a modality adapter, which adds a small block to the generality adapter in each layer and each modality in a parallel manner. Such a design could learn multilevel modality-specific representations with a modest number of parameters as the vast majority of parameters are shared with the generality adapter. We also design instance adapter to capture the appearance properties and temporal variations of a certain target. Moreover, to enhance the shared and specific features, we employ the loss of multiple kernel maximum mean discrepancy to measure the distribution divergence of different modal features and integrate it into each layer for more robust representation learning. Extensive experiments on two RGBT tracking benchmark datasets demonstrate the outstanding performance of the proposed tracker against the state-of-the-art methods. [ABSTRACT FROM AUTHOR]

Cooperative communication can significantly enhance the efficient utilization of spectrum in wireless networks. The performance of wireless cooperative networks depends on careful medium access control (MAC) and resource allocation such as relay selection and cooperative link scheduling policy for interference management. Most of the previous centralized works rely on precise instantaneous channel state information (CSI). In this paper, considering the impact of multirelay link interference on relay selection and dynamic spectrum sharing, we propose a fully distributed relay MAC scheme for wireless cooperative networks based on a Stackelberg game framework with only one-hop local CSI, where source nodes that have their own information to send act as leader users and where the others act as follower users. In this scenario, each relay node prices its spectrum resource to the corresponding source node to maximize its revenue. In addition, the proposed scheme helps not only source nodes to find relay nodes by channel gains and obtain an optimal system performance but relay nodes to maximize their revenue by asking a suitable resource price as well. The interactions between the sources and relays iteratively lead to a Stackelberg equilibrium, in which the cooperation system achieves high throughput and low transmission delay. Simulation results are presented to show the effectiveness of the proposed approach. [ABSTRACT FROM PUBLISHER]

The infrastructure-less and dynamic nature of mobile ad hoc networks demands a new set of networking strategies to improve the performance of quality of service (QoS). Providing QoS is a major issue in Manets. The traditional layered approach does not fit well for ad hoc networks due to high mobility and dynamic topology. This paper implements the cross layer design approach on DYMO routing protocol in Manets by using Qualnet simulator in both traditional layered approach and proposed cross layer approach. The proposed methodology uses four QoS metrics: throughput, end-to-end delay, packet delivery ratio and jitter. The experimental result reveals that QoS performance is enhanced in CLD approach for DYMO. The throughput in traditional layered approach for DYMO is 1961 b/s, whereas in the CLD approach it is 2986 b/s. Finally this paper concludes that cross layer approach significantly improves the QoS performance when compared with layered approach. [ABSTRACT FROM AUTHOR]

In this paper, we study the impact of human mobility on throughput and delay for people-centric applications in mobile ad hoc networks (MANETs). We consider a general human mobility model for MANETs, which can capture important features of human mobility, such as time correlation, node correlation, location heterogeneity, and node heterogeneity. Multiple unicasts with general arrival processes are delivered, and nodes are equipped with infinite buffers. Under our system model, we first characterize the network stability region in terms of the probability of each node set visiting each location and the amount of transmission resources at each location. We show that the node correlation and heterogeneity of locations' popularity usually decrease the size of the network stability region, whereas the diversity of locations visited by a node usually increases the size of the network stability region. Then, by solving a stability-related optimization problem, we develop a throughput-optimal policy based on the obtained optimal solution. We obtain the upper and lower bounds of the delay performance under the proposed policy. Finally, using simulations based on a theoretical model and some real traces, we verify the analytical results and compare the performance of the proposed policy with some existing policies. [ABSTRACT FROM PUBLISHER]

The “first wave” of wireless ad hoc routing protocols was heavily influenced by the routing algorithms used in wired networks. However, their overheads due to topology changes and the implicit restriction to point-to-point control messages meant that extensive effort had to be expended in “fixing” them to fit the intricacies and opportunities offered by wireless environments. In this paper, we analyze and compare the most widely used routing protocols in mobile ad hoc networks (MANETs). In particular, we consider routing and control overheads, storage requirements, and network setup costs of these protocols to see how well they fit in MANETs with nodes that have scarce resources. [ABSTRACT FROM PUBLISHER]

This paper studies the performance of a general two-hop relay (2HR)- $(x,w,f) $ packet delivery scheme that combines both erasure coding and packet replication techniques in mobile ad hoc networks (MANETs). Under this packet delivery scheme, a group of $x$ packets is first encoded into $w(w\geq x) $ coded packets using erasure coding, and each coded packet is then replicated to at most $f$ distinct relay nodes that can help to forward the coded packets to its destination node. The original packets can be recovered when $x$ distinct coded packets reach the destination node. To understand the packet delivery process under the 2HR- $(x,w,f) $ scheme, we develop a multidimensional Markov chain framework, and based on this analytical expressions on the packet delivery ratio and corresponding expected packet delivery cost are further derived. Finally, extensive simulation and numerical studies are conducted to illustrate the efficiency of the developed theoretical models and to illustrate our findings. Our results indicate that the replication parameter $f$ should be carefully selected in order to obtain a high packet-delivery-ratio performance while maintaining a relatively low delivery cost. [ABSTRACT FROM PUBLISHER]

In this paper, we analyze the impact of network coding (NC) configuration on the performance of ad hoc networks with the consideration of two significant factors, namely, the throughput loss and the decoding loss, which are jointly treated as the overhead of NC. In particular, physical-layer NC and random linear NC are adopted in static and mobile ad hoc networks (MANETs), respectively. Furthermore, we characterize the goodput and delay/goodput tradeoff in static networks, which are also analyzed in MANETs for different mobility models (i.e., the random independent and identically distributed (i.i.d.) mobility model and the random walk model) and transmission schemes (i.e., the two-hop relay scheme and the flooding scheme). Moreover, the optimal configuration of NC, which consists of the data size, generation size, and NC Galois field, is derived to optimize the delay/goodput tradeoff and goodput. The theoretical results demonstrate that NC does not bring about order gain on delay/goodput tradeoff for each network model and scheme, except for the flooding scheme in a random i.i.d. mobility model. However, the goodput improvement is exhibited for all the proposed schemes in mobile networks. To our best knowledge, this is the first work to investigate the scaling laws of NC performance and configuration with the consideration of coding overhead in ad hoc networks. [ABSTRACT FROM PUBLISHER]

Mobile Ad-hoc NETworks (MANETs) is a set of mobile nodes that can move around arbitrarily, and communicate with others in a multi-hop fashion without any assistance of base stations. With recent advances in Cognitive Radio (CR) technology, it is possible to apply the Dynamic Spectrum Access model in MANETs. This introduces the concept of Cognitive Radio Ad Hoc Networks (CRAHNs). Applying CR techniques provides better throughput, even in congested spectrum along with better propagation characteristics. CRAHN is a kind of intelligent network that is aware of its surrounding environment, and adapts to the transmission or reception parameters to achieve efficient communication without interfering with primary users. Routing in CR environment is a challenging task as the availability of channel is constrained by the presence of primary user. The problem of routing in CRAHNs targets the creation and maintenance of wireless multi-hop paths among cognitive nodes by deciding both the spectrum to be used and the relay nodes of the path. This paper proposes a cognitive cross-layer multipath probabilistic routing for cognitive radio based networks. The proposed solution uses spectrum holes identified by MAC layer, decides the channel to be used and transmit power level for each hop in the path. The proposed solution is implemented in NS2, and performance of the proposed solution is compared with the existing solution from the literature. The paper also shows that the proposed solution outperforms existing solution in terms of packet delivery ratio, average end-to-end delay and energy consumed per data packet. [ABSTRACT FROM AUTHOR]

In this paper, we present a methodology employing statistical analysis and stochastic geometry to study geometric routing schemes in wireless ad hoc networks. In particular, we analyze the network-layer performance of one such scheme, the random 1\over 2disk routing scheme, which is a localized geometric routing scheme in which each node chooses the next relay randomly among the nodes within its transmission range and in the general direction of the destination. The techniques developed in this paper enable us to establish the asymptotic connectivity and the convergence results for the mean and variance of the routing path lengths generated by geometric routing schemes in random wireless networks. In particular, we approximate the progress of the routing path toward the destination by a Markov process and determine the sufficient conditions that ensure the asymptotic connectivity for both dense and large-scale ad hoc networks deploying the random 1\over 2disk routing scheme. Furthermore, using this Markov characterization, we show that the expected length (hop count) of the path generated by the random 1\over 2disk routing scheme normalized by the length of the path generated by the ideal direct-line routing, converges to 3\pi /4 asymptotically. Moreover, we show that the variance-to-mean ratio of the routing path length converges to 9\pi ^2/64-1 asymptotically. Through simulation, we show that the aforementioned asymptotic statistics are in fact quite accurate even for finite granularity and size of the network. [ABSTRACT FROM PUBLISHER]

A sequence of online messages for connections is given, each message is important and thide failure of delivering a message is a critical event. The maximum lifetime problem maximizes the total number of messages that can be successfully sent over the network. Given a $$h\ge 1$$ , this paper presents two new problems on ad hoc networks (called the min-max and min-sum cost online problems), which adjust the initial energies of nodes such that the network can send the first $$h$$ messages. We consider the min-sum and min-max norms for minimizing the cost of adjusting the initial energies. This paper presents an algorithm for these problems and computes upper bounds for the total cost of the min-sum and min-max norms. Mohanoor et al. (Ad hoc Networks 7: 918-931, ) presented three algorithms (called SWRP, SFWP and SWCRP algorithms) to online energy aware routing, which, in practice, are better than other algorithms on lifetime in the cases: the effect of session length, transmission radius and node density. This paper modifies these algorithms (the modifies algorithms are called TSWRP, TSFWP and TSWCRP) so that they compute the total cost of the min-sum and min-max norms. Then, we show, in practice, the total cost of the min-sum and min-max norms computed by our algorithm are smaller than the values computed by the TSWRP, TSFWP and TSWCRP algorithms in the cases: the transmission radius and node density. Also, in practice, the lifetime of our algorithm is more than the lifetime of the SWRP, SFWP and SWCRP algorithms in the cases: the effect of session length and node density. [ABSTRACT FROM AUTHOR]

The study of energy constrained routing protocols in mobile Ad Hoc Networks (MANET) is attracting more attention recently. The typical MANET routing protocols of IETF are shortest routing protocols, that is, the least hops but do not consider the energy aware problem. Because the ad hoc networks is an energy constrained system with the portable devices, it is a very important metric to evaluate the routing protocols whether which have a longer network lifetime or not. Based on the mobile node energy level and using the different forward tactics, this paper presents an energy level based routing protocol-ELBRP. The routing protocol not only makes the system energy consumption low but also prolongs the system lifetime and improves the delay characteristic. In this paper, the proof of correctness and complexity analysis of ELBRP are given. This paper compares the performance of existing protocols AODV, RDRP and proposed ELBRP via simulation. The simulation result shows that ELBRP has a better delay performance, a lower energy consumption and longer network lifetime than the other two and provides an available approach to as hoc networks routing. [ABSTRACT FROM AUTHOR]