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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.

LoRa is a new low data-rate modulation technology for wireless communication, which uses spread spectrum communications to increase transmission distance. At present, sub-GHz LoRa is mainly used to build LoRaWAN and is applied to the monitoring and data collection of the Internet of Things (IoT). Focusing on the latest 2.4 GHz LoRa technology, this study introduces the characteristics of 2.4 GHz LoRa in the physical layer and experimentally analyzes the basic performance of communication, energy consumption, and ranging. Meanwhile, for the deficiencies of time on air in the evaluation of effective data rate, this study proposes the concepts of time on PHY and time of transmission (ToT). Then, the ToT duration of 2.4 GHz LoRa under different parameter configurations is calculated. Finally, combined with the physical-layer characteristics of 2.4 GHz LoRa, four potential networking topologies of the 2.4 GHz LoRa are listed, and their characteristics and application scenarios are analyzed. Compared with sub-GHz LoRa, 2.4 GHz LoRa is more applicable for building self-organized networks and worldwide IoT solutions.

The Mobile Ad Hoc Networks (MANETs) are useful in many applications environments and do not need any infrastructure support. Much work has been done on routing in MANETs. However, the proposed routing solutions only deal with the best effort data traffic. Connections with Quality of Service (QoS) requirements, such as voice channels with delay and bandwidth constraints, are not supported. The QoS routing has been receiving increasingly intensive attention in the wireline network domain. However, these QoS routing algorithms can not be applied directly to MANETs, because of the bandwidth constraints and dynamic network topology of MANETs. Searching for the shortest path with minimal cost and finding delay constrained least-cost paths are NP-complete problems. For this reason, approximated solutions and heuristic algorithms should be developed for multi-path constraints QoS routing. Also, to cope with changing of MANET topology, routing methods should be adaptive, flexible, and intelligent. In this paper, we propose a Genetic Algorithm (GA) based routing method for Mobile Ad-hoc Networks (GAMAN). Robustness rather than optimality is the primary concern of GAMAN. The GAMAN uses two QoS parameters for routing. The performance evaluation via simulations shows that GAMAN is a promising QoS routing algorithm for MANETs.

In this paper, we consider the behavior of a wireless ad-hoc sensor network for different radio models. By means of simulations, we analyze the performance of three protocols: AODV, DSR, and DSDV considering two radio models TwoRayGround and Shadowing.

In difference with other works, we generalize the type of radio model by allowing the path loss randomnesses to be present in the service environment of the network. We study the perceived Goodput and Depletion of the ad-hoc sensor network and compare the performance of three protocols for different scenarios. The simulation results confirm the fact that the shadowing phenomena, by destroying the regularity of the network, reduce the mean distance among nodes and at the same time increase the interference level and the latency of packet transmission. In particular, we found a maximum relative difference of 70%. On the other hand, for the proactive DSDV routing protocol the energy consumption rate seems to be independent of the radio model, at least for moderate size of the network (256 nodes). Also, we found that the packet delivery ratio of AODV and DSR routing protocols are more stable than DSDV protocol.

Symmetric Dicke states are a generalization of W-states that display interesting properties. These properties enable one to generate arbitrarily large symmetric Dicke states using operations on finite (2k) number of qubits. This paper formulates explicitly some basic results needed for this purpose. These results are synthesized into a generic Scalable Entangling Protocol. Examples are provided to illustrate the approach generality. A concomitant graphical representation allows fast comprehension of the protocol inputs, operations and outcomes.

This paper presents a distributed and concurrent multiple access-based collision avoidance MAC scheme to increase spatial reuse and hence the overall throughput of wireless networks. We make use of location information and power capture techniques to realize this protocol. While other wireless MAC protocols have used power capture technique in a general manner to reject the interfering signals during the entire reception of a packet, we exploit the additional capability of power capture to "lock-on" to the intended packet during a period known as "capture time" to admit other parallel transmissions. Simulation results show that our protocol can outperform the IEEE 802.11 throughput performance by a factor of 2 or more when there are short and medium range transmissions within a given area.

Multicasting protocols deliver data packets from a source node to multiple receivers, and serve a very important function in mobile ad-hoc networks (MANETs). In this paper, a novel receiver-initiated soft-state probabilistic multicasting protocol (RISP) for MANETs is proposed. RISP is inspired by the ant colony's route-seeking mechanism, in which an individual ant chooses the optimal path to its destination through cooperation with others in a totally distributed manner. Imitating the behaviour of ants in nature, RISP introduces probabilistic forwarding and soft-state for making relay decisions that are automatically adaptive to node mobility in MANETs. Compared with other protocols, we show by computer simulations that RISP has lower delivery redundancy, while achieving higher delivery ratio at all mobility scenarios. Furthermore, RISP has lower control overhead.

In this paper, we describe a novel architecture to enable a secure communication among mobile devices using different wirelesstechnologies like wireless LAN, Bluetooth, cellular systems or even infrared. Making use of the combination of these technologies for the data transmission and for the signaling of the communication, we analyze several scenarios with increasing complexity. The complete picture appears in the last scenario where all technologies are involved and the network is composed of heterogeneous mobile nodes. The paper also presents a solution for the setup of a secured communication channel (i.e. a Virtual Private Network connection) between several heterogeneous mobile nodes controlled by the cellular network operator. The mobile nodes can be either cellular aware or non-cellular aware in this framework. We propose to setup the heterogeneous network communications via the cellular network using the cellular aware nodes.

In the Broadcast Scheduling Problem (BSP), a finite set of stations are to be scheduled in a time division multiple access (TDMA) frame. In a TDMA frame, time is divided into equal length transmission slots. Unconstrained message transmission can result in a collision of messages, rendering them useless. Therefore, the objective of the BSP is to provide a collision free broadcast schedule which minimizes the total frame length or maximizes the slot utilization within the frame. In this chapter, we introduce the BSP as a NP-complete combinatorial optimization problem and discuss several heuristics which have been applied to the problem. The heuristics are tested on over 60 networks of varying sizes and densities and the results compared.