Route Discovery Phase Research Articles

Stable Routing Algorithm for Mobile Ad Hoc Network

Mobile Ad Hoc network is a multi-hop temporary autonomous system of mobile nodes with wireless transmitters and receivers without the aid of pre-established network infrastructure. With a great deal of different applications increasing, it needs to provide stable communication for such network. In this paper, a new routing algorithm is proposed which can dynamically estimate delay variety and calculate link stability factor. In the route discovery phase, it finds paths meeting delay requirement with greatest stable link. In the route maintenance phase, it effectively keeps monitoring network topology changes through delay prediction and performs rerouting in time. Furthermore, some enhancement strategies are adopted to control route acquisition latency and improve transmission quality. Simulation results show that it can meet with the delay requirement while decrease the routing cost. Comparing with other conventional routing algorithms, it can achieve higher packet delivery rate especially in rigorous network environment.

Acknowledgment based Reputation Mechanism to Mitigate the Node Misbehavior in Mobile Ad Hoc Networks

Problem statement: The cooperation between the nodes is essential to d iscover and maintain routes in mobile ad hoc network. Due to th e presence of misbehaving nodes, the node cooperation is not always guaranteed as the nodes a greed during the route discovery phase. This phenomenon results in frequent network partitioning and it makes the routing process difficult. It als o degrades the overall network performance and increases the control overhead due to frequent route discovery. Approach: This study proposed an Acknowledgment based Reputation Mechanism (ARM) to detected and isolated the misbehaving links in mobi le ad hoc networks. The proposed system introduced a novel dynamic acknowledgment ratio to make the nodes to request its second hop successor in the source route to acknowledge the receipt of the pack et. This makes the nodes to detect the behavior of the next hop links and to select the trusted routes for its transmissions. Results: The measured parameters such as packet drop ratio, malicious drop, false de tection and send buffer drop are reduced greatly. T he results also compared with the existing scheme and with original routing protocol performance. Conclusion/Recommendations: The proposed scheme performs better in detecting and isolating the misbehaving links. The overall network packet drop was decreased which in turn increase the overall network throughput. This shows that the proposed ac knowledgment scheme discovers the trusted routes with the presence of misbehaving nodes.

Automating the security analysis process of secure ad hoc routing protocols

Conventional security property evaluation approaches for ad hoc network routing protocols do not provide an automated or exhaustive capability. This paper provides an automated process to evaluate security properties in the route discovery phase for on-demand source routing protocols. For a given network topology, model checking is used to exhaustively evaluate protocol abstractions against an attacker attempting to corrupt the route discovery process. Additionally, topology reduction techniques are developed to reduce computational requirements while maintaining exhaustive analysis results.

An Energy Efficient Routing Protocol based on Periodic Route Discovery for Mobile Ad Hoc Networks

In present energy efficient protocols for mobile ad hoc networks, once the route is selected in the route discovery phase, the selected route is used until all the data packets are sent out or until the selected route fails due to the exhaustion of node battery energy. Due to the continuous flow of the packets through a selected route, and if a node in that route having less battery energy, then that node will certainly die out causing route failure and this may also cause failure of other routes which are connected to it. The problem being the energy level at this node is consumed and hence may lead to failure. To reduce this problem, a mechanism of periodic route discovery is introduced. In this mechanism, the route discovery process is reinitialized periodically to increase the network lifetime. It is observed from our simulation results that the proposed mechanism named “PRD based - MMBCR” performs better than the existing energy efficient protocols.

Research on AODV Routing Protocol Optimization in Wireless Sensor Network

Energy balance of nodes in wireless sensor network is a difficult point. In this paper, analyze the performance of AODV routing protocol applied to the coal mine WSN environment which has less mobile nodes. Base on its characteristic of lacking of energy efficiency and optimal route selection considerations, an improvement of AODV routing protocol is carried out. Route discovery phase of the algorithm use a cost metric routing strategy, according to the energy level of nodes and the quality of links to calculate the routing cost, lower cost routing path will be selected. Between efficient routing and energy balance make an effective trade-off, improve the delivery rate of the network.

Improving QoS-based Routing by Limiting Interference in Lossy Wireless Sensor Networks

Many new routing protocols have been proposed for wireless sensor networks to maximize throughput, minimize delay or improve other QoS metrics in order to solve the problems of resource-constrained sensor nodes in large networks. However, many of them are based on flooding or its variants. Many routing messages are propagated unnecessarily and may cause different interference characteristics during route discovery phase and in the actual application data transmission phase. As a result, incorrect routes may be selected. Epidemic algorithms have been used to limit flooding in the field of wireless sensor networks. Directed diffusion has been commonly used in wireless sensor networks because it is designed to improve energy efficiency and scalability. However, the intrinsic flooding scheme for interest subscriptions prevents it from achieving the maximal potential of these two goals. We propose a routing protocol that uses ID-free epidemic flooding to limit interference in conjunction with metrics for increasing throughput and reducing delay. Simulation results in ns2 show that there is an optimal number of neighbors to achieve the best throughput and delay performance. For a fixed topology of a certain size, there exists an optimal percentage of neighbors that forward the flooding message to achieve the best throughput and delay performance.

A Low Overhead Reachability Guaranteed Dynamic Route Discovery Mechanism for Dense MANETs

A crucial issue for a mobile ad hoc network is the handling of a large number of nodes. As more nodes join the mobile ad hoc network, contention and congestion are more likely. The on demand routing protocols which broadcasts control packets to discover routes to the destination nodes, generate a high number of broadcast packets in a larger networks causing contention and collision. We propose an efficient route discovery protocol, which reduces the number of broadcast packet, using controlled flooding technique. The simulation results show that the proposed probabilistic flooding decreases the number of control packets floating in the network during route discovery phase, without lowering the success ratio of path discoveries. Furthermore, the proposed method adapts to the normal network conditions. The results show that up to 70% of control packet traffic is saved in route discovery phase when the network is denser.

A Low Overhead Reachability Guaranteed Dynamic Route Discovery Mechanism for Dense MANETs

A crucial issue for a mobile ad hoc network is the handling of a large number of nodes. As more nodes join the mobile ad hoc network, contention and congestion are more likely. The on demand routing protocols which broadcasts control packets to discover routes to the destination nodes, generate a high number of broadcast packets in a larger networks causing contention and collision. We propose an efficient route discovery protocol, which reduces the number of broadcast packet, using controlled flooding technique. The simulation results show that the proposed probabilistic flooding decreases the number of control packets floating in the network during route discovery phase, without lowering the success ratio of path discoveries. Furthermore, the proposed method adapts to the normal network conditions. The results show that up to 70% of control packet traffic is saved in route discovery phase when the network is denser.

A Multipath QoS Routing with Route Stability for Mobile Ad Hoc Networks

Multihop wireless networks have emerged recently as an evolution of wireless network technology and are likely to be the integral part of future communication environment. In this context, support for quality of service (QoS) is becoming an inherent necessity rather than an additional feature of the network. This paper presents a route stability-based multipath QoS routing protocol for mobile ad hoc networks to support throughput and delay sensitive real-time applications in these networks. We incorporate a hop-by-hop admission control and a soft resource reservation scheme in a route discovery process to ensure QoS assurance to real-time applications. Further, a simple route stability model is utilized during both route discovery and maintenance phases for selecting QoS routes with higher stability. The reliability of the multiple QoS routes is improved through node disjointness and stability properties of the discovered routes. Following an effective QoS violation detection and route maintenance mechanism, the protocol reduces the frequency of route recovery leading to a significant reduction in QoS disruption. Extensive simulation studies show that the proposed routing protocol can support higher level of QoS in terms of packet delivery ratio, average end-to-end delay, maximum jitter, and overall network throughput.

A High Throughput On-Demand Routing Protocol for Multirate Ad Hoc Wireless Networks

Routing in wireless ad hoc networks is a challenging issue because it dynamically controls the network topology and determines the network performance. Most of the available protocols are based on single-rate radio networks and they use hop-count as the routing metric. There have been some efforts for multirate radios as well that use transmission-time of a packet as the routing metric. However, neither the hop-count nor the transmission-time may be a sufficient criterion for discovering a high-throughput path in a multirate wireless ad hoc network. Hop-count based routing metrics usually select a low-rate bound path whereas the transmission-time based metrics may select a path with a comparatively large number of hops. The trade-off between transmission time and effective transmission range of a data rate can be another key criterion for finding a high-throughput path in such environments. In this paper, we introduce a novel routing metric based on the efficiency of a data rate that balances the required time and covering distance by a transmission and results in increased throughput. Using the new metric, we propose an on-demand routing protocol for multirate wireless environment, dubbed MR-AODV, to discover high-throughput paths in the network. A key feature of MR-AODV is that it controls the data rate in transmitting both the data and control packets. Rate control during the route discovery phase minimizes the route request (RREQ) avalanche. We use simulations to evaluate the performance of the proposed MR-AODV protocol and results reveal significant improvements in end-to-end throughput and minimization of routing overhead.

Multipath Based QoS Routing in MANET

Routing protocols play an important role for communications in MANET. Multipath routing scheme can be distinguished because it can provide load balancing, fault-tolerance, and higher aggregate bandwidth. In this paper, a multipath source routing protocol with bandwidth and reliability guarantee is proposed. In routing discovery phase, the protocol selects several multiple alternate paths which meet the QoS requirements and the ideal number of multipath routing is achieved to compromise between load balancing and network overhead. In routing maintenance phase, it can effectively deal with route failures similar to DSR. Furthermore, the per-packet granularity is adopted in traffic allocation phase. Simulation results show that the proposed protocol remarkably increases the packet delivery rate and life-span of network with lower routing overhead. It will provide an effective solution for wireless communication.

Hierarchical Numbering Based Addressing and Stateless Routing Scheme for Wireless Sensor Networks

Due to energy and other relevant constraints, addressing of nodes and data routing techniques in sensor networks differ significantly from other networks. In this article, we present an energy-efficient addressing and stateless routing paradigm for wireless sensor networks. We propose a dynamic and globally unique address allocation scheme for sensors in such a way that these addresses can later be used for data routing. We build a tree like organization of sensors rooted by the sink node based on their transmission adjacency and then set labels on each sensor with a number according to the preorder traversal of the tree from the root. In this addressing process, each sensor keeps necessary information so that they can later route data packets to the destination depending on these addresses, without keeping the large routing table and running any no route discovery phase. Moreover, the scheme does not use location information as well (as done by geo-routing) and can be used in the indoor environment. We conduct simulations to measure the soundness of our approach and make a comparison with another similar technique TreeCast. Simulation results reveal that our approach performs better than its counterpart in several important performance metrics like address length and communication energy.

Enhanced AODV routing protocol for Bluetooth scatternet

Bluetooth is one of the most widespread technologies for personal area networks that allow portable devices to form multi-hop Bluetooth ad hoc networks, so called scatternets. Routing is one of the challenges in scatternets because of its impact on the performance of the network. It should focus on reducing the power consumption in the network because most of the nodes are battery-operated portable devices. In this paper, we propose a routing protocol for Bluetooth scatternets that customizes the Ad hoc On-Demand Distance Vector (AODV) routing protocol by making it power-aware and suitable for scatternets. It enhances the AODV flooding mechanism by excluding all non-bridge slaves from taking apart in the AODV route discovery process. In addition, it improves the AODV route discovery phase by considering the hop count, the predicated node’s power, and the average traffic intensity for each node as metrics for best route selection. By removing HELLO packets, our protocol reduces the control packets overhead and the power consumption in network devices. Simulation results show that the proposed protocol achieved considerable improvements over other enhanced AODV protocols by increasing the data delivery ratio by 10.78%, reducing the average end-to-end delay by 8.11%, and reducing the average energy consumption by 7.92%.

Game theoretic approach in routing protocol for wireless ad hoc networks

This paper introduces a game theoretic method, called forwarding dilemma game (FDG), which controls routing overhead in dense multi-hop wireless ad hoc networks. The players of the game are the wireless nodes with set of strategies { Forward, Not forward}. The game is played whenever an arbitrary node in the network receives a flooding packet. In FDG, every player needs to know the number of players of the game. That is why a neighbor discovery protocol (NDP) is introduced. In order for NDP to function, a field is attached to the flooding packets (routing overhead packets). The mixed strategy Nash equilibrium is used as a solution for the FDG. This provides the probability that the flooding packet would be forwarded by the receiver node. FDG with NDP is implemented in AODV protocol in Network Simulator NS-2 to verify its performance with simulations. FDG with NDP improves performance of the AODV compared to the same network with only AODV protocol in moderate and high node densities. FDG can be applied to any routing protocol that uses flooding in the route discovery phase.

Arithmetic Encoding Based Dynamic Source Routing for Ad-Hoc Networks

An ad hoc network is a collection of mobile stations forming a temporary network without the aid of any centralized coordinator. Routing messages are an essential component of Mobile Adhoc Networks, as each packet needs to be passed quickly through intermediate nodes from source to destination. Internal threats due to changes in the node behaviour that target the routing discovery or maintenance phase of the routing protocol and security challenges can however lead to insecure communication in MANETS. We proposed a model that found the improper behaviour of the nodes and eliminated them. Also it provided secure routing mechanism of sharing messages between source and destination by modifying and making use of Arithmetic encoding that not only saved the bandwidth but also provided the security by crypting the data. The reason we chose Arithmetic coding was because it typically enabled very high coding efficiency and provided better security.

A New Distance Based Route Maintenance Strategy for Dynamic Source Routing Protocol

Although DSR can respond a route quickly, it yields a long delay when a route is rebuilt. This is because when source node receives RERR packet, it will try to find alternative routes from the route cache. If alternative routes are not available, the source node, then, will enter route discovery phase to find new routes. We introduced a new route maintenance strategy by utilizing location information, called the DISTANCE (DIstance baSed rouTe maintenANCE) algorithm. The DISTANCE algorithm works by adding another node (called bridge node) into the source list to prevent the link from failure. From the simulation result, the DISTANCE algorithm improved the performance of DSR in terms of packet sending ratio, delay and routing overhead.

Energy-aware load-balaning fault-tolerant routing scheme for ad hoc sensor networks

Most routing protocols for sensor networks try to extend network lifetime by minimizing the energy consumption, but have not taken the network reliability into account. An energy-aware, load-balancing and fault-tolerant routing scheme, termed as ELFR was propsed to adapt to the harsh environment. First a network robustness model was presented. Based on this model, the route discovery phase was designed to make the sensors to construct into a hop-leveled network which is mesh structure. A cross-layer design was adopted to measure the transmission delay so as to detect the failed nodes. The routing scheme works with acknowledge (ACK) feedback mechanism to transfer control messages to avoid producing extra control overhead messages. When nodes fail, the new healthy paths will be selected locally without rerouting. Simulation results show that our scheme is much robust, and it achieves better energy efficiency, load balancing and maintains good end-to-end delay.

Prediction based location aided routing for mobile ad hoc networks

Routing in ad hoc networks faces significant challenges due to node mobility and dynamic network topology. In this work we propose the use of mobility prediction to reduce the search space required for route discovery. A method of mobility prediction making use of a sectorized cluster structure is described with the proposal of the Prediction based Location Aided Routing (P‐LAR) protocol. Simulation study and analytical results of P‐LAR find it to offer considerable saving in the amount of routing traffic generated during the route discovery phase.

New hierarchical approach to reactive routing protocols for wireless ad hoc networks with cross-layer design

A hierarchical routing protocol is designed for reactive ad hoc networks. In the hierarchical architectures network nodes are classified as Mobile Nodes (MNs) and Forwarding Nodes (FNs). FNs are selected from MNs during the route discovery phase of the reactive routing. This FN selection algorithm is distributed, dynamic and requires no additional protocol messaging other than used during the route discovery. The FN selection algorithm is further improved by using network congestion information from Medium Access (MAC) layer. The protocol is implemented using Dynamic Source Routing (DSR) protocol, and the new protocol is called HDSR. Simulation results show that HDSR significantly improves the routing efficiency in wireless ad hoc networks.

A Localized Route Discovery for On-Demand Routing Protocols in Event-Driven Wireless Sensor Networks

In this paper, the problem of Redundant Duplicated RREQ Network-wide Flooding (RDRNF), induced by multiple sensor nodes during route discovery in event-driven wireless sensor networks, is described. In order to reduce the number of signaling messages during the route discovery phase, a novel extension, named the Localized Route Discovery Extension (LRDE), to the on-demand ad hoc routing protocol, is proposed. The LRDE reduces energy consumption during route discovery. The heuristically and temporarily selected Path Set-up Coordinator (PSC) plays the role of a route request broker that alleviates redundant route request flooding. The LRDE also sets a route path be aggregation-compatible. The PSC can effectively perform data aggregation through the routing path constructed by the LRDE. The simulation results reveal that significant energy is conserved by reducing signaling overhead and performing data aggregation when LRDE is applied to on-demand routing protocols.