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Opportunistic routing is a promising technique that has been proposed for wireless mesh networks. It achieves significant performance gains under unstable wireless links since it can take advantage of the broadcast nature of the wireless medium. Many protocols of opportunistic routing have been proposed to increase transmission reliability and network throughput. Instead of using a dedicated next hop, opportunistic routing can consider multiple downstream nodes as potential forwarders. The decision of which nodes being chosen to forward packets is made by the coordination schema. Although the coordination helps opportunistic routing to deliver opportunistic gains, it requires a batch-based schedule to minimize the cost, which may prevent spatial channel reuse and thus under utilize wireless media. In this paper, we explain the fundamental idea of opportunistic routing and propose a discrete-time Markov chain as a general model to map the transmission process. It demonstrates how to map batch-based packet transmissions in the network with state transitions in a Markov chain. Our model considers the pipelined data transfer and evaluates opportunistic routing under different wireless networks in terms of the expected number of transmissions and time slots. It shows both the pros and cons of opportunistic routing and thus helps in the design of future protocols of opportunistic routing. [ABSTRACT FROM AUTHOR]

Software-defined networking (SDN) is a representative next generation network architecture, which allows network administrators to programmatically initialize, control, change, and manage network behavior dynamically via open interfaces. SDN is widely adopted in systems like 5G mobile networks and cyber-physical systems (CPS). However, SDN brings new security problems, e.g., controller hijacking, black-hole, and unauthorized data modification. Traditional firewall or IDS based solutions cannot fix these challenges. It is also undesirable to develop security mechanisms in such an ad hoc manner, which may cause security conflict during the deployment procedure. In this paper, we propose OSCO (Open Security-enhanced Compatible OpenFlow) platform, a unified, lightweight platform to enhance the security property and facilitate the security configuration and evaluation. The proposed platform supports highly configurable cryptographic algorithm modules, security protocols, flexible hardware extensions, and virtualized SDN networks. We prototyped our platform based on the Raspberry Pi Single Board Computer (SBC) hardware and presented a case study for switch port security enhancement. We systematically evaluated critical security modules, which include 4 hash functions, 8 stream/block ciphers, 4 public-key cryptosystems, and key exchange protocols. The experiment results show that our platform performs those security modules and SDN network functions with relatively low computational (extra 2.5% system overhead when performing AES-256 and SHA-256 functions) and networking performance overheads (73.7 Mb/s TCP and 81.2Mb/s UDP transmission speeds in 100Mb/s network settings). [ABSTRACT FROM AUTHOR]

The characteristics of MANET such as decentralized architecture, dynamic topologies make MANETs susceptible to various security attacks. Sequence number attacks are such type of security threats which tend to degrade the network functioning and performance by sending fabricated route reply packets (RREP) with the objective of getting involved in the route and drop some or all of the data packets during the data transmission phase. The sequence number adversary attempts to send a fabricated high destination number in the RREP packet which attracts the sender to establish a path through the adversary node. This paper proposes a proactive secure routing mechanism which is an improvement over the authors previously proposed scheme. It makes use of linear regression mechanism to predict the maximum destination sequence number that the neighboring node can insert in the RREP packet. As an additional security checkpoint, it uses a bait detection mechanism to establish confidence in marking a suspicious node as a malicious node. The proposed approach works in collaboration with the ad hoc on-demand distance vector routing (AODV) protocol. The simulation results depict that the approach improves the network performance in the presence of adversaries as compared to previously proposed scheme. [ABSTRACT FROM AUTHOR]

Due to the dynamism of topology, sharing of bandwidth and constraint of resources in wireless nodes, the provision of quality of service (QoS) for routing in mobile ad hoc networks (MANETs) presents a great challenge. Security is another crucial aspect of providing QoS since the existence of malicious nodes present all kinds of threats to MANETs. Although a number of mechanisms have been proposed for protecting MANETs, most of the solutions are only effective for a particular kind of attacks or provide security at the cost of sacrificing QoS. In this paper, we propose a trust-based secure QoS routing scheme by combining social and QoS trust. The primary approach of the proposed scheme relies on mitigating nodes that exhibit various packet forwarding misbehavior and on discovering the path that ensures reliable communication through the trust mechanism. The scheme would select the best forwarding node based on packet forwarding behavior as well as capability in terms of QoS parameters, such as residual energy, channel quality, link quality, etc. We will present an adversary model for packet dropping attack against which we evaluate the proposed scheme. Simulation experiment using Network Simulator-2 (NS2) and under various network conditions show that mixing social and QoS trust parameters can greatly improve security and quality of service routing in terms of overhead, packet delivery ratio and energy consumption. [ABSTRACT FROM AUTHOR]

Due to the absence of infrastructure support, secure data dissemination is a challenging task in scalable mobile ad hoc networks (MANETs) environment. In most of the traditional routing techniques for MANETs, either security has not been taken into account or only one aspect of security concern has been addressed without optimizing the routing performance. This paper proposes Flooding Factor based Framework for Trust Management (F3TM) in MANETs. True flooding approach is utilized to identify attacker nodes based on the calculation of trust value. Route Discovery Algorithm is developed to discover an efficient and secure path for data forwarding using Experimental Grey Wolf algorithm for validating network nodes. Enhanced Multi-Swarm Optimization is used to optimize the identified delivery path. Simulations are carried out in ns2 to assess and compare the performance of F3TM with the state-of-the-art frameworks: CORMAN and PRIME considering the metrics including delay, packet delivery ration, overhead and throughput. The performance assessment attests the reliable security of F3TM compared to the state-of-the-art frameworks. [ABSTRACT FROM AUTHOR]

In order to guarantee the QoS of multimedia applications in a mobile ad hoc network (MANET), a reliable packet transmitting mechanism used in MANETs is developed. In this paper, we synthesize the geographical information, bit error rates of the links and 2-hop routing information to elaborate a most durable routing path between the source node and the destination node. In route discovery phase, all the possible paths from the source node to the destination node are checked on the basis of path reliability and number of hops. Meanwhile, 2-hop routing tables are created. Aided by the geographical information, our mechanism can reduce broadcast packets significantly in RREQ phase compared with other flooding-based protocols. The 2-hop routing information is employed just like backup node information used in other stable routing protocols. Once the path breaks, it can be repaired locally and rapidly by setting up a short path to a 2-hop neighboring node. Compared with other four stable mechanisms with excellent performance, our mechanism (B2RP) exhibits a slightly better in terms of packet delivery ratio, average route lifetime and end-to-end delay. [ABSTRACT FROM AUTHOR]

In large scale mobile ad hoc networks (MANETs), it is effective to reduce the load of routing by introducing hierarchical routing, and it is conducted by clustering of nodes. A clustering mechanism based on the diffusion equation is a typical autonomous clustering in MANETs, and gives appropriate clustering if all the node degrees are uniform. However, node degrees in MANETs are heterogeneous in general, the fact causes the difference in the strength of diffusion effect. This difference causes that the position of cluster head tends to be around the boundary of networks and degrade battery efficiency of nodes. In this paper, by introducing an asymmetric diffusion depending on node degree, we propose a new clustering method independent of heterogeneity of node degrees. We show that the proposed method has efficient characteristics for battery consumption. In addition, we show the comparison of the proposed method with the conventional method with respect to the efficiency of routing. [ABSTRACT FROM AUTHOR]

AODV and DSR are normally taken as a standard in reactive routing protocols for Mobile Ad-Hoc Network (MANETs). Both of these protocols are widely used in different applications of MANET because of their simple design and better performance. AODV does not provide optimal results in the scenarios where we have heavy traffic with large number of connections and higher routing load. In this paper, we have introduced a novel idea of 'Reliability Factor' to determine reliable links between the intermediate nodes; based on this factor a reactive routing protocol is proposed, the simulation results of Reliability Factor Based Routing Protocol show that it outperforms AODV and SP-AODV in terms of better packet delivery fraction, routing load and end-to-end delay. [ABSTRACT FROM AUTHOR]

Mobile ad hoc network, is nowadays becoming extremely famous in research vicinity. A range of protocols and methodology is coming into account to resolve an assortment of issues associated with a mobile ad hoc network. The nodes in mobile ad hoc network are present in ad hoc fashion i.e.; they are connecting to each other without using wires. In addition, they do not necessitate any central authority for performing their tasks. This thing creates mobile ad hoc network active and disseminated in character. In this paper, we implemented improved Watchdog protocol called as I-Watchdog protocol with Destination-Sequenced Distance-Vector Routing (DSDV) routing protocol that provides efficient and secure routing with prevention of denial of service attack as well as detection of congestion in the network background. In this paper, proposed I-Watchdog procedure does proficient recognition of the presence of malicious nodes in a mobile ad hoc network as well as it finds the genuine reason of the happening of loss of packets. Additionally, we will analysis the improved performance of mobile ad hoc network in the presence of DSDV with I-Watchdog protocol in provisions of packet drop ratio (PDR), throughput along with end-to-end delay. [ABSTRACT FROM AUTHOR]

The various applications of Delay Tolerant Networking (DTNs) require a suitable routing protocol for urban environment. In general, the mobile node trajectory is associate with its social relations and regular life in urban areas, and existing DTN routing protocols cannot incorporate in urban environments. This study aims to improve the key targets, such as delivery ratio, latency and network overhead ratio, in urban environments by describing a routing algorithm based on Geographic Grid (GeoGrid). GeoGrid is suitable for a sensory data collection system in which a part of the mobile nodes generate data, and mobile relay nodes transport the data to a fixed sink station. Simulation experiments were carried out to verify the performance of the proposed GeoGrid under an urban scenario, and the results suggest that the GeoGrid outperforms both Epidemic and Prophet routing algorithms in successful delivery ratio, average delivery latency, and network overhead ratio. [ABSTRACT FROM AUTHOR]

Wireless sensor networks (WSNs) were envisaged to become the fabric of our environment and society. However, they are yet unable to surmount many operational challenges such as limited network lifetime, which strangle their widespread deployment. To prolong WSN lifetime, most of the existing clustering schemes are geared towards homogeneous WSN. This paper presents enhanced developed distributed energy-efficient clustering (EDDEEC) scheme for heterogeneous WSN. EDDEEC mainly consists of three constituents i.e., heterogeneous network model, energy consumption model, and clustering-based routing mechanism. Our heterogeneous network model is based on three energy levels of nodes. Unlike most works, our energy consumption model takes into account the impact of radio environment. Finally, the proposed clustering mechanism of EDDEEC changes the cluster head selection probability in an efficient and dynamic manner. Simulation results validate and confirm the performance supremacy of EDDEEC compared to existing schemes in terms of various metrics such as network life. [ABSTRACT FROM AUTHOR]

Delay-Tolerant Networks (DTNs) are characterized by time-varying and partially connected network topology. In such networks, mobility of node may be by virtue of its carrier. Social beings such as humans may act as a carrier of mobile nodes, and therefore mobility pattern of node follows a social-based movement model. Due to intermittent connectivity, end-to-end path between source and destination is rare and therefore message delivery is a challenge in such networks. In this paper, we present a new routing approach, context-aware community-oriented routing (CONCOR) that exploits the community and the context awareness of nodes, for efficient message delivery. Nodes with a common point of interest form a dynamic community. We have identified a set of node's attribute (context) and formulated a utility function to determine its capability to deliver a message. CONCOR is a multihop routing approach exploiting the nodes as message relays (store-carry-forward). Through simulation, we validated the effectiveness of node's attributes in estimation of message delivery probability. The simulations were done for our approach using the social movement-based data set on Opportunistic Network Environment (ONE) simulator. We compared our approach with dynamic social grouping (DSG)-based routing and context-aware routing(CAR) on three metrics viz. message delivery ratio, message traffic ratio and average message delay. We found that the results of our approach outperforms the DSG and CAR on all the three metrics. [ABSTRACT FROM AUTHOR]

The problems of hot spot and energy consumption of nodes in wireless sensor networks (WSNs) have been tackled by the adoption of hybrid energy efficient distributed (HEED) and unequal clustering algorithm to prolong the network lifetime (UCAPN) protocols. These have involved the implementation of unequally sized clusters that are based on the distance of cluster head (CH) from the base station (BS). The BS partitions the network area into several radially divided zones depending on the distance from centre of the field and CHs are independently selected in each zone. Clustering, on the other hand, controls how data are transmitted and allows for aggregation in the clusters. However, whereas these topologies have been able to improve network life time, the problem of network void still persists. To address this, a radially optimized zone-divided energy-aware WSN protocol using bat algorithm is proposed. This protocol considers not only the distance from the BS, but also the angle at which the WSN develops. It gives a unique and equal opportunity for each sensor network to have ambience area for communicating and sensing necessary for its routing operations. Besides, it divides the sensing area into radial zones and employs the unequal clustering method in these zones to resolve the hot-spot problem. Based on the merits of zone-divided networks, CHs with great residual energy present in the high-energy regions are selected as the relay node in the inter-cluster multi-hop routing stage. Simulation results show that the proposed technique outperforms both HEED and UCAPN protocols. Bat algorithm is capable of predicting most critical nodes and generates a scalable and feasible energy-efficient routing technique for radially optimized zone-divided energy-aware WSN. By exploiting the angle at which the WSN develops, this protocol avails equal opportunity for each sensor network to have enough fields for communicating and sensing necessary for its routing operations. Using bat algorithm not only gives a superior packet delivery ratio, hence reducing voids, but also saves on energy consumption at the nodes. Sensor nodes are grouped into clusters to improve network performance. [ABSTRACT FROM PUBLISHER]

Opportunistic or delay-tolerant networks (DTNs) may be used to enable communication in case of failure or lack of infrastructure (disaster, censorship, remote areas) and to complement existing wireless technologies (cellular, WiFi). Wireless peers communicate when in contact, forming an impromptu network, whose connectivity graph is highly dynamic and only partly connected. In this harsh environment, communication algorithms are mostly local search heuristics, choosing a solution among the locally available ones. Furthermore, they are routinely evaluated through simulations only, as they are hard to model analytically. Even when more insight is sought from models, these usually assume homogeneous node meeting rates, thereby ignoring the attested heterogeneity and nontrivial structure of human mobility. We propose DTN-Meteo, a new unified analytical model that maps an important class of DTN optimization problems over heterogeneous mobility/contact models into a Markov chain traversal over the relevant solution space. (Heterogeneous) meeting probabilities between different pairs of nodes dictate the chain's transition probabilities and determine neighboring solutions. Local optimization algorithms can accept/reject candidate transitions (deterministically or randomly), thus “modulating” the above transition probabilities. We apply our model to two example problems: routing and content placement. We predict the performance of state-of-the-art algorithms (SimBet, BubbleRap) in various real and synthetic mobility scenarios and show that surprising precision can be achieved against simulations, despite the complexity of the problems and diversity of settings. To our best knowledge, this is the first analytical work that can accurately predict performance for utility-based algorithms and heterogeneous node contact rates. [ABSTRACT FROM PUBLISHER]

Content-Centric Networks (CCNs) are fundamental evolutionary technologies that promise to form the cornerstone of the future Internet. The information flow in these networks is based on named data requesting, in-network caching, and forwarding, which are unique and can be independent of IP routing. As a result, common IPbased network tools such as ping and traceroute can neither trace a forwarding path in CCNs nor feasibly evaluate CCN performance. We propose ?contrace,? a network tool for CCNs (particularly, CCNx implementation running on top of IP) that can be used to investigate the round-trip time (RTT) between content forwarder and consumer, the states of in-network cache per name prefix, and the forwarding path information per name prefix. We report a series of experiments conducted using contrace on a CCN topology created on a local testbed and the GEANT network topology emulated by the Mini-CCNx emulator. The results confirm that contrace is not only a useful tool for monitoring and operating a network, but also a helpful analysis tool for enhancing the design of CCNs. Further, contrace can report the number of received interests per cache or per chunk on the forwarding routers. This enables us to estimate the content popularity and design more effective cache control mechanisms in experimental networks. [ABSTRACT FROM PUBLISHER]

Dynamic Spectrum Allocation using Cognitive Radio (CR) is a promising solution to the spectrum availability problem in wireless networks. Cognitive Radio, however, opens up certain new issues, mainly at the physical, medium access control and routing layer levels. Several solutions have been proposed to tackle these issues and use dynamic spectrum allocation to improve the performance of wireless networks. The focus of most of these has been to improve the throughput and other Quality of Service (QoS) metrics. However, energy spent by a node is also an important matter of concern in most wireless networks e.g. wireless sensor networks. In this paper, we focus on the challenges posed by CR in routing data in an energy efficient manner. We then study some existing solutions to route data energy efficiently in CR networks and suggest some directions for future research. [ABSTRACT FROM AUTHOR]

When evaluating the performance of routing protocols in wireless mesh network (WMN), we need deeper analysis from the aspect of network traffic complexity to show how traffic characteristics are influenced by routing protocols and node mobility. The predictability of network traffic can be used as one metric of complexity and can be analyzed by multi-scale entropy (MSE) method. With 20 different random waypoint (RWP) mobility scenarios and with destination sequenced distance vector (DSDV), a typical proactive protocol, and Ad hoc on-demand distance vector (AODV), a typical reactive protocol, the predictabilities of aggregated traffic of gateway in WMN are analyzed using MSE method to show how different routing protocols bear different mobility scenarios. The MSE results show that the aggregated traffic of gateway with DSDV is more difficult to be predicted than that with AODV for different mobility scenarios. The maxspeed parameter of RWP dominates the traffic predictability for AODV. Both of the pause time and the maxspeed parameters, have great influence on the traffic predictability for DSDV. The reasons lie in the behaviors of routing protocols, i.e., AODV has up-to-date paths while DSDV does not. [ABSTRACT FROM AUTHOR]

Providing better communication and maximising the communication performance in a Underwater Wireless Sensor Network (UWSN) is always challenging due to the volatile characteristics of the underwater environment. Radio signals cannot properly propagate underwater, so there is a need for acoustic technology that can support better data rates and reliable underwater wireless communications. Node mobility, 3-D spaces and horizontal communication links are some critical challenges to the researcher in designing new routing protocols for UWSNs. In this paper, we have proposed a novel routing protocol called Layer by layer Angle-Based Flooding (L2-ABF) to address the issues of continuous node movements, end-to-end delays and energy consumption. In L2-ABF, every node can calculate its flooding angle to forward data packets toward the sinks without using any explicit configuration or location information. The simulation results show that L2-ABF has some advantages over some existing flooding-based techniques and also can easily manage quick routing changes where node movements are frequent. [ABSTRACT FROM AUTHOR]

In this paper, the influence of the features of the propagation channel in the performance of Mobile Ad Hoc Networks (MANET) is studied. In order to overcome the possible propagation limitations, a particular reconfigurable multiantenna terminal configuration for MANETs is provided, along with an optimization procedure to select the proper radiation pattern at each node of the network. The adequate selection of the radiation pattern at each node lets maximize the transmission/reception capabilities of the wireless network, depending on the propagation channel features and their evolution in time. In addition, a modified routing strategy is proposed, based on the existence of an alternative route at each node, provided that the main one is not available because of propagation issues or incidences in the network. [ABSTRACT FROM AUTHOR]

Vehicular ad hoc network (VANET) is a communication network used for vehicle to vehicle interaction and this network is different from other wireless networks. Geographical Routing Protocol (GRP) is used in VANETs. This study proposes a Fuzzy Quality of Service GRP (FQ_GRP) to enhance the performance of GRP routing. Link quality, traffic density and number of intersections are inputs to a fuzzy system and the fuzzy controller output is next hop selection. Simulations are conducted with 40 nodes around 9 square kilometers. The proposed FQ_GRP routing scheme, distributes the traffic through nodes so that the throughput is increased and average latency reduced. The proposed method achieves better throughput and lower end to end delay compared to traditional GRP. [ABSTRACT FROM AUTHOR]

Most of the nodes in ad hoc networks rely on batteries, which requires energy saving. Hence, numerous energy-efficient routing algorithms have been proposed for solving this problem. In this paper, we exploit the benefits of cross-layer information exchange, such as the knowledge of the Frame Error Rate (FER) in the physical layer, the maximum number of retransmissions in the Medium Access Control (MAC) layer and the number of relays in the network layer. Energy-consumption-based Objective Functions (OF) are invoked for calculating the end-to-end energy consumption of each potentially available route for both Traditional Routing (TR) and for our novel Opportunistic Routing (OR), respectively. We also improve the TR and the OR with the aid of efficient Power Allocation (PA) for further reducing the energy consumption. For the TR, we take into account the dependencies amongst the links of a multi-hop route, which facilitates a more accurate performance evaluation than upon assuming the links that are independent. Moreover, two energy-efficient routing algorithms are designed based on Dijkstra's algorithm. The algorithms based on the energy OF provide the theoretical bounds, which are shown to be close to the bound found from exhaustive search, despite the significantly reduced complexity of the former. Finally, the end-to-end throughput and the end-to-end delay of this system are analyzed theoretically and a new technique of characterizing the delay distribution of OR is proposed. The simulation results show that our energy-efficient OR outperforms the TR and that their theoretical analysis accurately matches the simulation results. [ABSTRACT FROM PUBLISHER]

Behavioral patterns prediction in the context of Vehicular Ad hoc Networks (VANETs) has been receiving increasing attention due to the enabling of on-demand, intelligent traffic analysis and real-time responses to traffic issues. One of these patterns, sequential patterns, is a type of behavioral pattern that describes the occurrence of events in a timely and ordered fashion. In the context of VANETs, these events are defined as an ordered list of road segments traversed by vehicles during their trips from a starting point to their final intended destination. In this paper, a new set of formal definitions depicting vehicular paths as sequential patterns is described. Also, five novel communication schemes have been designed and implemented under a simulated environment to collect vehicular paths; such schemes are classified under two categories: RSU (Road Side Unit)-based and Vehicle-based. After collection, extracted frequent paths are obtained through data mining, and the probability of these frequent paths is measured. In order to evaluate the effectiveness and efficiency of the proposed schemes, extensive experimental analysis has been realized. [ABSTRACT FROM AUTHOR]

Mobile Ad-Hoc Networks (MANETs) are autonomous and decentralized wireless systems. Mobile Ad hoc Network is a collection of mobile nodes in which the wireless links are frequently broken down due to mobility and dynamic infrastructure. Routing is a significant issue and challenge in ad hoc networks. Many Routing protocols have been proposed so far to improve the routing performance and reliability. This research paper describes the characteristics of ad hoc routing protocols Ad-hoc On Demand Distance Vector Routing (AODV), Dynamic Source Routing (DSR), Hybrid Routing (ZRP) based on the performance metrics like Average delay, Throughput under low mobility and low traffic network as well as under high mobility and high traffic network for Black hole effect and Daniel of Service(DoS) using NS-2. Results show that AODV has maximum throughput under low traffic and DSDV has maximum throughput under high traffic. As network becomes dense DSR perform well in terms of Throughput than AODV and DSR and ZRP. [ABSTRACT FROM AUTHOR]

This paper introduces a novel multi-copy routing protocol, called predict and forward (PF), for delay tolerant networks, which aims to explore the possibility of using mobile nodes as message carriers for end-to-end delivery of the messages. With PF, the message forwarding decision is made by manipulating the probability distribution of future inter-contact and contact durations based on the network status, including wireless link condition and nodal buffer availability. In particular, PF is based on the observations that the node mobility behavior is semi-deterministic and could be predicted once there is sufficient mobility history information. We implemented the proposed protocol and compared it with a number of existing encounter-based routing approaches in terms of delivery delay, delivery ratio, and the number of transmissions required for message delivery. The simulation results show that PF outperforms all the counterpart multi-copy encounter-based routing protocols considered in the study. [ABSTRACT FROM AUTHOR]

Delay Tolerant Networks (DTNs) provide message delivery services to users via intermittently connected nodes. In DTNs, routing is one of the most challenging issues since end-to-end connectivity between nodes may not be available most of the time. Although many routing protocols for DTNs have been proposed, they do not achieve satisfactory performance, since they exploit only some of the network characteristics. In this paper, we present a new DTN routing protocol, called the Link Contact Duration-based Routing Protocol (LCD). Like existing protocols, LCD uses the disconnect duration of a link between two nodes to find the routing path with the shortest end-to-end delay. In addition, LCD uses the contact duration of a link and the number of buffered messages to deliver as many messages as possible in a short time. Our simulation results show that LCD has better performance than existing DTN routing protocols. [ABSTRACT FROM AUTHOR]

Cooperative communication (CC) allows multiple nodes to simultaneously transmit the same packet to the receiver so that the combined signal at the receiver can be correctly decoded. Since the CC can reduce the transmission power and extend the transmission coverage, it has been considered in minimum energy routing protocols to reduce the total energy consumption. However, previous research on cooperative routing only focuses on minimizing the total energy consumption from the source node to the destination node, which may lead to the unbalanced energy distribution among nodes. In this paper, we aim to study the impact of cooperative routing on balancing the energy distribution among nodes. By introducing a new routing scheme which carefully selects cooperative relay nodes and assigns their transmission power, our cooperative routing method can balance the remaining energy among neighboring nodes to maximize the lifetime of the network. Simulation results demonstrate that the proposed cooperative routing algorithm significantly balances the energy distribution and prolongs the lifetime of the network. [ABSTRACT FROM AUTHOR]

Mobile Ad Hoc Network (MANET) is a collection of wireless mobile nodes dynamically forming a temporary network without the use of any existing network infrastructure or centralized administration. Mobile Ad Hoc Networks (MANETs) have the attributes such as wireless connection, continuously changing topology, distributed operation and easy of deployment. Each node operates not only as an end system, but also as a router to forward packets. Routing in MANETs has been a challenging task ever since the wireless networks came into existence. The MANET routing protocols can be broadly classified into two classes: Proactive routing protocols (or table-driven routing protocols) and Reactive routing protocols (or on-demand routing protocols). In this research work we have compared the performance of two Proactive routing protocols: DSDV and OLSR, along with AODV as a Reactive routing protocol using Random Waypoint (RWP) Mobility Model, Freeway (FW) Mobility Model, Manhattan Grid (MH) Mobility Model and Reference Point Group (RPGM) Mobility Model using Network Simulator (NS-2.34). These four Mobility Models are selected to represent the possibility of practical application in future such as movement of nodes on Highway, in urban area, in groups such as movement in military battlefield etc. [ABSTRACT FROM AUTHOR]

We propose a new multipath-based reliable routing protocol on MANETs, Multipath-based Reliable routing protocol with Fast-Recovery of failures (MRFR). For reliable message transmission, MRFR tries to find the most reliable path between a source and a destination considering the end-to-end packet reception reliability of the routes. The established path consists of a primary path that is used to transmit messages, and the secondary paths that are used to recover the path when detecting failures on the primary path. After establishing the path, the source transmits messages through the primary path. If a node detects a link failure during message transmission, it can recover the path locally by switching from the primary to the secondary path. By allowing the intermediate nodes to locally recover the route failure, the proposed protocol can handle the dynamic topological change of the MANETs efficiently. The simulation result using the QualNet simulator shows that the MRFR protocol performs better than other protocols in terms of the end-to-end message delivery ratio and fault-tolerance capability. [ABSTRACT FROM AUTHOR]