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In this paper, we study broadcasting protocols where nodes use some of their neighbors to forward messages. We propose a new protocol based on a variant of neighbor elimination scheme using RNG graph to ensure a full coverage of the network. The computation of RNG uses two kinds of distance: a geometrical one and and neighborhood-based distance that permits to use our protocol without positioning system. This protocol, called RRS for RNG Relay Subset, provides a self-selecting forwarding neighbor operating mode which guarantees a fair broadcast loading. In RRS a node v is a relay for a node u if and only if v is a neighbor of u and v has a RNG-neighbor which is not covered by u transmission. Moreover, experiments with 802.11-like MAC layer show that RRS is efficient.

Location verification in wireless sensor networks (WSNs) is quite challenging in the presence of malicious sensor nodes, which are called attackers. These attackers try to break the verification protocol by reporting their incorrect locations during the verification stage. In the literature of WSNs, most of the existing methods of location verification use a set of trusted verifiers, which are vulnerable to attacks by malicious nodes. These existing methods also use some distance estimation techniques, which are not accurate in noisy channels. In this article, we adopt a statistical approach for secure location verification to overcome these limitations. Our proposed method does not rely on any trusted entities and it takes care of the limited precision in distance estimation by using a suitable probability model for the noise. The resulting verification scheme detects and filters out all malicious nodes from the network with a very high probability even when it is in a noisy channel.

Over the last few years, research has provided the cellular network system with the capability of fair channel access to multimedia users, while at the same time, insuring a given QoS and optimal utilization of network resources. Scheduling policies play a crucial role in achieving desired QoS goals and optimum utilization of limited resources. Many scheduling approaches have been proposed for the efficient utilization of the network resources. This paper deals with the experimental study of a new proposed scheduling policy for achieving fairness, QoS, and optimal use of resources. The proposed scheduling policy Code Division Multiple Access based on Generalized Processor Sharing with Dynamic Weights (CDMA/GPS-DW) is an improvement of a previous GPS policy. Simulation results show that the proposed policy achieves fairness of the specified QoS and makes efficient use of the network resources.

Nowadays, more and more federated learning algorithms have been implemented in edge computing, to provide various customized services for mobile users, which has strongly supported the rapid development of edge intelligence. However, most of them are designed relying on the reliable device-to-device communications, which is not a realistic assumption in the wireless environment. This paper considers a realistic aggregation problem for federated learning in a single-hop wireless network, in which the parameters of machine learning models are aggregated from the learning agents to a parameter server via a wireless channel with physical interference constraint. Assuming that all the learning agents and the parameter server are within a distance $\mathrm{\Gamma }$ from each other, we show that it is possible to construct a spanning tree to connect all the learning agents to the parameter server for federated learning within $O(log\mathrm{\Gamma })$ time steps. After the spanning tree is constructed, it only takes $O(log\mathrm{\Gamma })$ time steps to aggregate all the training parameters from the learning agents to the parameter server. Thus, the server can update its machine learning model once according to the aggregated results. Theoretical analyses and numerical simulations are conducted to show the performance of our algorithm.

We prove that any collection of n discs in which each one intersects at most k others, can be colored with at most O(log³ k) colors so that for each point p in the union of all discs there is at least one disc in the collection containing p whose color differs from that of all other members of the collection that contain p. This is motivated by a problem on frequency assignment in cellular networks, and improves the best previously known upper bound of O(log n) when k is much smaller than n.

Given a set of unit disks in the plane with union area A, what fraction of A can be covered by selecting a pairwise disjoint subset of the disks? Rado conjectured 1/4 and proved 1/4.41. Motivated by the problem of channel assignment for wireless access points, in which use of 3 channels is a standard practice, we consider a variant where the selected subset of disks must be 3-colourable with disks of the same colour pairwise-disjoint. For this variant of the problem, we conjecture that it is always possible to cover at least 1/1.41 of the union area and prove 1/2.09. We also provide an O(n²) algorithm to select a subset achieving a 1/2.77 bound. Finally, we discuss some results for other numbers of colours.

Recent years have seen a surge of interest in the field of pervasive context-aware computing. In this framework we propose a novel real implementation of an adaptive self-configurable system, applied within the scope of wireless ad-hoc networks. WiDFuNC is an integrated system that consists of an intelligent unit implemented on a real PDA, a number of sensors and a remote server device to form an efficient prototype system that can be applied in various domains. This implementation of WiDFuNC focuses on pure classification problems with satisfactory experimental results, presenting great adaptability and context-awareness.

This paper tackles the issue of constrained multicast routing in wireless networks using a hybrid soft computing-based algorithm. Recent developments in multimedia applications and the dynamic and rapidly changed environment of the wireless networks make the constrained multicast routing a real challenge. The problem can be formulated as minimizing a multicast tree cost under several constraints or Quality of Service (QoS) metrics. This problem has been proven to be NP-complete. The proposed hybrid algorithm is based on a population based incremental learning algorithm that combines in an efficient way the features of genetic algorithms and competitive learning. Experimental results show that, in most cases, the proposed algorithm yields better solutions than other heuristic algorithms proposed in the literature.

A typical data mining approach to network intrusion detection mandates a training dataset of network events labeled as either normal or a particular attack category. Such a training dataset is usually very large since there are many events to track. This is particularly the case in a WLAN where the number of devices communicating with the WLAN can be large and with adhoc connectivity. The large size of the unlabeled training dataset creates a problem for the domain expert who is asked to label the records toward creating a training dataset. We present an effective approach by which the number of network records the expert has to examine is a relatively small proportion of the given training dataset. A clustering algorithm is used to form relatively coherent groups which the expert examines as an entity to label records as one of four classes: Red (definite intrusion), Yellow (possibly intrusion), Blue (probably normal), and Green (definite normal). Subsequently, an ensemble classifier-based data cleansing approach is used to detect records that were likely mislabeled by the expert. The proposed approach is investigated with a case study of a large real-world WLAN. In addition, ensemble classifier-based intrusion detection models built using the labeled training dataset demonstrate the effectiveness of the labeling process with good generalization accuracy over multiple test datasets.

Mobile ad hoc networks (MANETs) are ad hoc networks in which the nodes co-operatively route the traffic to the destination nodes which are beyond the wireless range of source nodes. The nodes in the network act as both end devices and routers. The routing mechanism in MANETs differentiates it from other wireless networks. Developing a routing protocol which is light on resources and efficient is a challenging task. Several routing protocols have been developed but the reactive routing protocols have found favor in most applications since these obtain the route when a node has data to send. This results in lower routing load and better conservation of meagre resources of the nodes. The two prominent reactive routing protocols for mobile ad hoc networks-Dynamic Source Routing (DSR) and Ad-hoc On-demand Distance Vector (AODV) routing. Both the protocols have similar on-demand behavior, but the differences in the protocol mechanism can lead to significant performance differentials. The performance differentials are analyzed using varying network load and mobility.

This paper compares the reliability performance of five adaptive and two fixed routing algorithms in the context of a simplified military wireless network. The network is abstracted as a circuit switched network where the connectivity can change. The five algorithms are shown to differ widely in their sensitivity to the gain parameter, transient behavior and response to increasing load or lost trunk capacity. All the adaptive algorithms had a higher transient call blocking ratio under general overload conditions than an optimized fixed algorithm where the originating switch retains supervision of the call. This is consistent with the philosophy of network design that adaptive routing is most valuable when the network configuration is not fully known or when local overloads exist but additional capacity is available elsewhere. These results are applicable to commercial as well as military wireless systems. Interference on a wireless connection can lead to changes in network topology, or a local overload may exist at a congested node, creating the conditions where adaptive routing algorithms are useful.

Ad hoc networks are useful for providing communication support where no fixed infrastructure exists or the deployment of a fixed infrastructure is not economically profitable, and movement of communicating parties is allowed. Therefore, such networks are designed to operate in widely varying environments, from military networks to low-power sensor networks and other embedded systems. Frequent topology changes caused by node mobility make routing in ad hoc wireless networks a challenging problem.

In this paper, we propose an efficient ad hoc routing algorithm, which we refer to as GZRP, a hybrid protocol that makes use of the ZRP scheme and the Global Positioning System (GPS). As opposed to the ZRP original scheme, our GZRP scheme consists of propagating the routing (query) messages only to the nodes that are further away from the query source. We discuss the algorithm, its implementation, and report on the performance of GZRP scheme, and compare it to the ZRP routing protocol using an extensive simulation experiment. Our results indicate clearly that GZRP outperforms ZRP by reducing significantly the number of route query messages, and thereby increases the efficiency of the network load. Furthermore, we show that careful GPS screening angle is an important factor in the success of the GZRP ad hoc routing protocol.

We propose a novel medium access control protocol for ad hoc wireless networks data to send can contend simultaneously for the channel. Nodes contend for access using a synchronous signaling mechanism that achieves two objectives: it arbitrates contentions locally and it selects a subset of nodes across the network that attempt to transmit simultaneously. The subset of nodes that survive the signaling mechanism can be viewed as an orchestrated set of transmissions that are spatially reusing the channel shared by the nodes. Thus the 'quality' of the subset of nodes selected by the signaling mechanism is a key factor in determining the spatial capacity of the system. In this paper, we propose a general model for such synchronous signaling mechanisms and recommend a preferred design. We then focus via both analysis and simulation on the spatial and capacity characteristics of these access control mechanisms. Our work is unique in that it specifically focuses on the spatial capacity aspects of a MAC protocol, as would be critical for ad hoc networking, and shows SCR is a promising solution. Specifically, it does not suffer from congestion collapse as the density of contending nodes grows, it does not suffer from hidden or exposed node effects, it achieves high capacities with a spatial usage exceeding 1 (i.e. more than one packet exchange in the area covered by a transmission), and it facilitates the integration of new physical layer capacity increasing technologies.

We present Delay-Energy Aware Routing (DEAP) a novel protocol for heterogeneous wireless ad hoc networks. DEAP is a crosslayer scheme that: first, manages adaptively the energy control by controlling the wakeup cycle of sensors based on the experienced packet delay; and second, rout packet in each hoc by distributing the load a group of neighboring nodes. The primary result of DEAP is that it enables a flexible and wide range of tradeoffs between the packet delay and the energy consumption. Therefore, DEAP supports delay sensitive applications of heterogeneous networks that include sensors and actors. DEAP is scalable to the change in network size, node type, node density and topology. DEAP accommodates seamlessly such network changes, including the presence of actors in heterogeneous sensor networks. Indeed, while DEAP does not count on actors, it takes advantage of them, and uses their resources when possible, thus reducing the energy consumption of sensor nodes. Through analysis and simulation evaluations, we show that DEAP improves the packet delay and network lifetime compared to other protocols.

The traditional teaching system uses local area network to realize online teaching, which leads to high stability and hardware load of the teaching system and makes it difficult to meet the teaching demand. To solve the above problems, a dance movement distance learning system based on wireless network communication technology is designed. On the B/S architecture, the hardware control module and communication module of the system are designed. The fuzzy set principle is used to evaluate the students’ dance cognitive ability, so as to personalize the recommended teaching contents. The teaching video is compressed according to H.264/AV compression standard to reduce the system transmission and processing load. The system functionality test results show that the maximum transmission packet loss rate of the designed system is 8.3%, and the lost data does not interfere with teaching, has low computer memory consumption, and has superior performance.

The work described in this paper proposes and evaluates an end-to-end communication approach in realizing terminal mobility in IP wireless access networks. The proposed network architecture also provides a solution to multi-homing in IPv4 and IPv6 networks. It concentrates on end-to-end abstraction and does not require any special service from the underlay network infrastructure. The multi-homing capability is used to achieve seamless handoff. Based on multi-homing we also propose and evaluate a handoff scheme that exploits the overlapping coverage area and speed of the mobile node between sub-networks. We describe the network architecture and show its mobility and multi-homing capability by prototype implementation and by performance evaluation. Our implementation does not have any significant bad performance impact on plain versions of IPv4 and IPv6. The evaluation of handoff scheme shows that packet loss and handoff latency can be reduced significantly even with the end-to-end design, depending upon the characteristics of underlay wireless access network.

Wireless ad hoc networks are self-organized groups of mobile devices that are able to communicate with each other using a wireless physical medium. A critical issue in ad hoc networks is how to maintain network activities in order to achieve maximum lifespan despite energy constraints. The aim of power management of routing protocols is to prolong the lifetime of the entire network and to increase the delivery rate of transactions carried out through the mobile network.

We define a Quality-of-Power-Service (QoPS) metric to evaluate the efficiency of power-aware unicast routing protocols. The aim of these protocols is to increase the longevity of ad hoc networks. QoPS metric is applied to different position-based power-aware unicast routing protocols. Our simulation results confirm that power-relative distribution of data streams in multi-path unicast routing protocols distributes energy consumption to multiple nodes and thus increase the network's lifetime. Moreover, the experiments show that multi-path protocols provide excellent scalability and high delivery success rate. The locality distribution phenomenon discovered by the simulations explains, on the one hand, the improved scalability and the long lifetime of large, dense, and high-degree wireless networks, and on the other hand, the short lifetime of small, sparse, and low-degree networks.

In this paper, we study the connected r-hop k-dominating set problem in wireless networks. We propose two algorithms for the problem. We prove that algorithm I for UDG has (2r + 1)³ approximate ratio for k ≤ (2r + 1)² and (2r + 1)((2r + 1)² + 1)-approximate ratio for k > (2r + 1)². And algorithm II for any undirected graph has (2r + 1)ln(Δ_r) approximation ratio, where Δ_r is the largest cardinality among all r-hop neighborhoods in the network. The simulation results show that our algorithms are efficient.

In this paper, we address the problem of gathering information in one node (sink) of a radio network where interference constraints are present: when a node transmits, it produces interference in an area bigger than the area in which its message can actually be received. The network is modeled by a graph; a node is able to transmit one unit of information to the set of vertices at distance at most d_T in the graph, but when doing so it generates interferences that do not allow nodes at distance up to d_I(d_I ≥ d_T) to listen to other transmissions. We are interested in finding a gathering protocol, that is an ordered sequence of rounds (each round consists of noninterfering simultaneous transmissions) such that w(u) messages are transmitted from any node u to a fixed node called the sink. Our aim is to find a gathering protocol with the minimum number of rounds (called gathering time). In this article, we focus on the specific case where the network is a path with the sink at an end vertex of the path and where the traffic is unitary (w(u) = 1 for all u); indeed this simple case appears to be already very difficult. We first give a new lower bound and a protocol with a gathering time that differ only by a constant independent of the length of the path. Then we present a method to construct incremental protocols. An incremental protocol for the path on n + 1 vertices is obtained from a protocol for n vertices by adding new rounds and new calls to some rounds but without changing the calls of the original rounds. We show that some of these incremental protocols are optimal for many values of d_T and d_I (in particular when d_T is prime). We conjecture that this incremental construction always gives optimal protocols. Finally, we derive an approximation algorithm when the sink is placed in an arbitrary vertex in the path.

In this paper, we consider the problem of gathering information in a gateway in a radio mesh access network. Due to interferences, calls (transmissions) cannot be performed simultaneously. This leads us to define a round as a set of non-interfering calls. Following the work of Klasing, Morales and Pérennes, we model the problem as a Round Weighting Problem (RWP) in which the objective is to minimize the overall period of non-interfering calls activations (total number of rounds) providing enough capacity to satisfy the throughput demand of the nodes. We develop tools to obtain lower and upper bounds for general graphs. Then, more precise results are obtained considering a symmetric interference model based on distance of graphs, called the distance-$d$ interference model (the particular case $d=1$ corresponds to the primary node model). We apply the presented tools to get lower bounds for grids with the gateway either in the middle or in the corner. We obtain upper bounds which in most of the cases match the lower bounds, using strategies that either route the demand of a single node or route simultaneously flow from several source nodes. Therefore, we obtain exact and constructive results for grids, in particular for the case of uniform demands answering a problem asked by Klasing, Morales and Pérennes.