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Widespread usage of unmanned aerial vehicles (UAVs) in new and emerging applications needs dynamic and adaptive networking. The development of routing protocols for UAV ad hoc networks faces numerous issues because of the unique characteristics of UAVs, such as rapid mobility, frequent changes in network topology, and limited energy consumption. The Optimized Link State Routing (OLSR) protocol seems to be a promising solution as it offers improved delay performance. It is expected that OLSR will satisfy the strict demands of real-time UAV applications such as "search and rescue" (SAR) missions as it involves the most recent update of routing information. The classical OLSR routing protocol and its enhanced versions, D-OLSR, ML-OLSR, and P-OLSR, use different techniques to make an appropriate decision for routing packets. These routing techniques consider the quality of a wireless link, type of antenna, load, and mobility-aware mechanism to select the best UAV to send the message to the destination. This study evaluates and examines the performance of the original and modified OLSR routing protocols in UAV ad hoc networks for three SAR scenarios: (1) increasing mobility, (2) increasing scalability, and (3) increasing the allowed space of UAVs. It analyzes and validates the performance of the four OLSR-based routing protocols. It determines the best OSLR routing protocol by taking into account the packet delivery ratio, latency, energy consumption, and throughput. The four routing protocols and the SAR scenarios were simulated using NS-3.32. Based on the simulation results, ML-OLSR outperforms OLSR, D-OLSR, and P-OLSR in the considered measures. [ABSTRACT FROM AUTHOR]

A mobile ad hoc network (MANET) has several intrinsic features that create unique queuing dynamics, and thus congestion control inside a MANET must be achieved under time-critical conditions. Meanwhile, the Named Data Networking (NDN) architecture ensures traffic optimization and has attracted renewed attention as part of the future internet. The synergy between NDN and MANETs can be exploited in order to improve the performance of dynamic content routing and congestion control mechanisms. This overview identifies the key concepts involved in congestion control for NDN-based MANETs. It also proposes some criteria for categorising existing congestion control solutions for NDN-based MANETs and discusses the advantages and disadvantages of each category. Future challenges regarding congestion control for NDN-based MANETs are also highlighted. [ABSTRACT FROM AUTHOR]

Mobile Ad-hoc NETworks (MANETs) allow wireless networks to exist where there is no or limited network infrastructure. They have attracted renewed attention as part of the 5G approach to device densification, while they remain very relevant to natural disaster response. The reader will benefit from the techniques concentrated upon in this overview article, in particular Multiple Description Coding (MDC) or Scalable Video Coding, with multipath delivery, with which it is feasible to stream video across MANETs. However, the article's two case studies demonstrate that video quality and Quality of Experience (QoE) depend on node density and node speed within a MANET. Higher node speeds are also relevant to Vehicular Ad Hoc Networks (VANETs) and Vehicle to Everything (V2X) technology, which the article also touches upon. This overview identifies the key concepts involved in video streaming over MANETs and VANETs, including as well a large number of relevant references. [ABSTRACT FROM AUTHOR]

and host. A packet might travel through multiple intermediary ad hoc nodes in order to arrive to its destination, while the nature of wireless multi-hop channel is bringing in various types of packet losses. This paper focuses on three main reasons of online packet losses in MANETs: (1) losses due to wireless link errors; (2) losses due to congestion; and (3) losses due to route alteration. It proposes a deep learning-based algorithm for packet loss discrimination. The algorithm uses the backpropagation neural network (BPNN) concept. We performed simulation experiments for evaluating the performance of the proposed loss discrimination algorithm under different network configurations. Through simulation results, we confirmed that the proposed algorithm improves packet loss discrimination and route alteration in the network. It also reduces congestion and increases network throughput. [ABSTRACT FROM AUTHOR]

In mobile ad hoc networks (MANETs), the IEEE 802.11 CSMA/CA is deployed as the primary medium access control (MAC) layer protocol to schedule the access to the wireless medium. The IEEE 802.11 standard was designed with the assumption that nodes would never deviate from the protocol. However, MANET nodes may purposefully show misbehavior at the MAC layer to obtain more bandwidth or degrade the network performance and disrupt the network services. This paper reviews and classifies the most important strategies generating MAC layer misbehavior based on their objectives and operating principles. Then, it examines some of the recent proposed solutions and mechanisms for detecting and preventing MAC layer misbehavior. A comparison of the studied solutions is carried out using a set of critical evaluation metrics. Finally, the paper concludes with a brief summary of key ideas and a general direction that can provide a basis for future work. [ABSTRACT FROM AUTHOR]

In the IEEE 802.11 standard, network nodes experiencing collisions on the shared medium need a mechanism that can prevent collisions and improve the throughput. Furthermore, a backoff mechanism is used that uniformly selects a random period of time from the contention window (cw) that is dynamically controlled by the Binary Exponential Backoff (BEB) algorithm. Prior research has proved that the BEB scheme suffers from a fairness problem and low throughput, especially under high traffic load. In this paper, we present a new backoff control mechanism that is used with the IEEE 802.11 distributed coordination function (DCF). In particular, we propose a dynamic, deterministic contention window control (DDCWC) scheme, in which the backoff range is divided into several small backoff sub-ranges. In the proposed scheme, several network levels are introduced, based on an introduced channel state vector that keeps network history. After successful transmissions and collisions, network nodes change their cw based on their network levels. Our extensive simulation studies show that the DDCWC scheme outperforms four other well-known schemes: Multiplicative Increase and Linear Decrease, Double Increment Double Decrement, Exponential Increase Exponential Decrease, and Linear/Multiplicative Increase and Linear Decrease. Moreover, the proposed scheme, compared with the IEEE 802.11 DCF, gives 30.77% improvement in packet delivery ratio, 31.76% in delay, and 30.81% in throughput. [ABSTRACT FROM AUTHOR]

By applying the principles of MANETs, a vehicular ad-hoc network (VANET) [2] can be established in an ad-hoc mode by vehicles. In the third paper [5], the authors introduce an epidemic algorithm (EPIC) for message dissemination in VANETs. From another perspective, existing routing protocols for VANETs often use several metrics to select the best route in a VANET. [Extracted from the article]

Mobile ad hoc networks (MANETs) possess numerous and unique characteristics, such as high channel error-rate, severe link-layer contentions, frequent link breakage (due to node mobility), and dissimilar path properties (e.g., bandwidth, delay, and loss rate) that make these networks different from the traditional ones. These characteristics seriously interfere with communication and hence, ultimately degrade the overall performance in terms of end-to-end delay, packet delivery ratio, network throughput, and network overhead. The traditional referenced layered strict architecture is not capable of dealing with MANET characteristics. Along with this, the most important apprehension in the intent of MANETs is the battery-power consumption, which relies on non-renewable sources of energy. Even though improvements in battery design have not yet reached that great a level, the majority of the routing protocols have not emphasized energy consumption at all. Such a challenging aspect has gained remarkable attention from the researchers, which inspired us to accomplish an extensive literature survey on power-aware optimization approaches in MANETs. This survey comprehensively covers power-aware state-of-the-art schemes for each suggested group, major findings, crucial structures, advantages, and design challenges. In this survey, we assess the suggested power-aware policies in the past in every aspect so that, in the future, other researchers can find new potential research directions. [ABSTRACT FROM AUTHOR]

Mobile ad hoc networks (MANETs) use algorithms that schedule transmissions in a fair and efficient manner. A multihop scheduler schedules transmissions so that the channel utilization is maximized while guaranteeing the quality of service (QoS) for all nodes. QoS-based scheduling in MANETs must be obtained under time-critical conditions as these networks have several features that produce unique queuing dynamics. Schedulers in MANETs take into account various QoS parameters such as end-to-end packet delay, packet delivery ratio, flow priority, etc. Also, scheduling in MANETs takes many forms such as distributed priority, fair, opportunistic, etc. This article provides a survey of scheduling techniques for MANETs and discusses the advantages and disadvantages of each category. [ABSTRACT FROM AUTHOR]