Academic literature on the topic 'Minimum routing overhead'

A wireless ad hoc network is a dispersed type of wireless network. The network is called as ad hoc as it does not rely on any pre existing infrastructure. Routing decisions are ready by node itself, so the determination of which node to forward data is prepared dynamically based on network connectivity. The overhead of a route discovery cannot be neglected. In this, Neighbour coverage protocol proposes for reducing routing overhead and to utilize the neighbour coverage knowledge and the probabilistic mechanism, which can radically decrease the number of retransmissions to reduce the routing overhead, and can also improve the routing performance. Due to high mobility of nodes in ad hoc networks, there exist regular link breakages, which lead to frequent path failures and route discoveries. ALERT dynamically partitions the network field into zones and arbitrarily chooses nodes in zones as intermediate relay nodes, which form a non-traceable unsigned route. In addition, it conceals the data initiator/receiver among many initiators/receivers to build up source and destination anonymity protection. Thus, ALERT offers anonymity security to sources, destinations, and routes for effective counter intersection and timing attacks and overheads are reduced.

As the size of devices are scaling down at rapid pace, the interconnect delay play a major part in performance of IC chips. Therefore minimizing delay and wire length is the most desired objective. FLUTE (Fast Look-Up table) presented a fast and accurate RSMT (Rectilinear Steiner Minimum Tree) construction for both smaller and higher degree net. In this paper, FLUTE presented an optimization technique that reduces time complexity for RSMT construction for both smaller and larger degree nets. However for larger degree net this technique induces memory overhead, as it does not consider the memory requirement in constructing RSMT. Since availability of memory is very less and is expensive, it is desired to utilize memory more efficiently which in turn results in reducing I/O time (i.e. reduce the number of I/O disk access). The proposed work presents a Memory Optimized RSMT (MORSMT) construction in order to address the memory overhead for larger degree net. The depth-first search and divide and conquer approach is adopted to build a Memory optimized tree. Experiments are conducted to evaluate the performance of proposed approach over existing model for varied benchmarks in term of computation time, memory overhead and wire length. The experimental results show that the proposed model is scalable and efficient.

As the size of devices are scaling down at rapid pace, the interconnect delay play a major part in performance of IC chips. Therefore minimizing delay and wire length is the most desired objective. FLUTE (Fast Look-Up table) presented a fast and accurate RSMT (Rectilinear Steiner Minimum Tree) construction for both smaller and higher degree net. FLUTE presented an optimization technique that reduces time complexity for RSMT construction for both smaller and larger degree nets. However for larger degree net this technique induces memory overhead, as it does not consider the memory requirement in constructing RSMT. Since availability of memory is very less and is expensive, it is desired to utilize memory more efficiently which in turn results in reducing I/O time (i.e. reduce the number of I/O disk access). The proposed work presents a Memory Optimized RSMT (MORSMT) construction in order to address the memory overhead for larger degree net. The depth-first search and divide and conquer approach is adopted to build a Memory optimized tree. Experiments are conducted to evaluate the performance of proposed approach over existing model for varied benchmarks in terms of computation time, memory overhead and wire length. The experimental results show that the proposed model is scalable and efficient.

In wireless ad hoc networks, the traditional routing protocols make the route selection based on minimum distance between the nodes and the minimum number of hop counts. Most of the routing decisions do not consider the condition of the network such as link quality and residual energy of the nodes. Also, when a link failure occurs, a route discovery mechanism is initiated which incurs high routing overhead. If the broadcast nature and the spatial diversity of the wireless communication are utilized efficiently it becomes possible to achieve improvement in the performance of the wireless networks. In contrast to the traditional routing scheme which makes use of a predetermined route for packet transmission, such an opportunistic routing scheme defines a predefined forwarding candidate list formed by using single network metrics. In this paper, a protocol is proposed which uses multiple metrics such as residual energy and link quality for route selection and also includes a monitoring mechanism which initiates a route discovery for a poor link, thereby reducing the overhead involved and improving the throughput of the network while maintaining network connectivity. Power control is also implemented not only to save energy but also to improve the network performance. Using simulations, we show the performance improvement attained in the network in terms of packet delivery ratio, routing overhead, and residual energy of the network.

Technology advancement in the field of vehicular ad hoc networks (VANETs) improves smart transportation along with its many other applications. Routing in VANETs is difficult as compared to mobile ad hoc networks (MANETs); topological constraints such as high mobility, node density, and frequent path failure make the VANET routing more challenging. To scale complex routing problems, where static and dynamic routings do not work well, AI-based clustering techniques are introduced. Evolutionary algorithm-based clustering techniques are used to solve such routing problems; moth flame optimization is one of them. In this work, an intelligent moth flame optimization-based clustering (IMOC) for a drone-assisted vehicular network is proposed. This technique is used to provide maximum coverage for the vehicular node with minimum cluster heads (CHs) required for routing. Delivering optimal route by providing end-to-end connectivity with minimum overhead is the core issue addressed in this article. Node density, grid size, and transmission ranges are the performance metrics used for comparative analysis. These parameters were varied during simulations for each algorithm, and the results were recorded. A comparison was done with state-of-the-art clustering algorithms for routing such as Ant Colony Optimization (ACO), Comprehensive Learning Particle Swarm Optimization (CLPSO), and Gray Wolf Optimization (GWO). Experimental outcomes for IMOC consistently outperformed the state-of-the-art techniques for each scenario. A framework is also proposed with the support of a commercial Unmanned Aerial Vehicle (UAV) to improve routing by minimizing path creation overhead in VANETs. UAV support for clustering improved end-to-end connectivity by keeping the routing cost constant for intercluster communication in the same grid.

Opportunistic routing utilizes the broadcast nature of wireless networks, significantly promoting the unicast throughput. Many variations of opportunistic routing designs have been proposed, although all of the current designs consistently rely on all of the topology information to construct forwarder lists and process data forwarding, which indeed restricts the application in large-scale wireless networks, where collecting global optimal information is very costly. In this paper, we propose the localized opportunistic routing (LOR) protocol, which utilizes the distributed minimum transmission selection (MTS-B) algorithm to partition the topology into several nested close-node-sets (CNSs) using local information. LOR can locally realize the optimal opportunistic routing for a large-scale wireless network with low control overhead cost. Since it does not use global topology information, LOR highlights an interesting tradeoff between the global optimality of the used forwarder lists and scalability inferred from the incurred overhead. Extensive simulation results show that LOR dramatically improves performances over extremely opportunistic routing (ExOR) and MAC-independent opportunistic routing protocol (MORE), which are two well-known designs from the literature, in terms of control overhead, end-to-end delay, and throughputs. It also exhibits promising performance in vehicular ad hoc networks (VANETs).

In mobile ad hoc networks (MANETs), link failures are caused frequently because of node’s mobility and use of unreliable wireless channels for data transmission. Multipath routing strategy can cope with the problem of the traffic overloads while balancing the network resource consumption. In the paper, an optimized node-disjoint multipath routing (ONMR) protocol based on ad hoc on-demand vector (AODV) is proposed to establish effective multipath to enhance the network reliability and robustness. The scheme combines the characteristics of reverse AODV (R-AODV) strategy and on-demand node-disjoint multipath routing protocol to determine available node-disjoint routes with minimum routing control overhead. Meanwhile, it adds the backup routing strategy to make the process of data salvation more efficient in case of link failure. The results obtained through various simulations show the effectiveness of the proposed scheme in terms of route availability, control overhead and packet delivery ratio.

Background and Objective: Two different variants of secure routing algorithms are proposed in the present work. In both the variants a stable route is established between source and destination. Methods: The selected route is associated with the nodes having sufficient energy to establish the route and to transmit the data packets, minimum velocity to reduce the frequency of link failure, maximum distance from the source node to reduce the number of hops in the selected route, minimum number of neighbors to reduce the routing overhead. Each variant has two phases. In the first phase it is assumed that the selected route has no attackers. The first phase is made more realistic in the second phase by considering the presence of attacker in the selected route. In the first variant a node associated with the selected route overhears the transmission of the next forwarder node to detect an attacker node in the routing path. But a node may fail to overhear its next hop in presence of hidden node, due to limited overhear range etc. Such problem is eliminated in the second variant. In the second variant each node associated with the selected route searches its data packet buffer for the reception of the next data packet from its predecessor node associated with the same route and suspects the predecessor node as an attacker in case the next data packet is not found in the buffer. The performance of both the variants is compared on the basis of packet delivery ratio, throughput and average end-to-end delay. Results: The throughput and packet delivery ratio are higher in the second variant than the first variant whereas the average end-to-end delay is less in the second variant than the first variant. Conclusion: Moreover both the variants outperform the existing schemes in terms of packet delivery ratio, throughput and average end-to-end delay.

A HIP multicast mode; based dynamic multicast routing algorithm (HIPDMR) was brought out and network model was established to describe and simplify problem to be researched. HIPDMR used Bellman-Ford as routing search algorithm, which can determine dynamic multicast routing with minimum hop number and overhead while meet constraints of bandwidth, delay, jitter and packet loss rate. Simulation experiments result show that HIPDMR can build dynamic multicast routing under constraints of multiple QoS comparing with algorithms that not considering QoS assuming network node output link capacity be equal

A Mobile Ad hoc Network (MANET) is a collection of wireless mobile nodes forming a temporary network without the need for base stations or any other pre–existing network infrastructure. In a peer-to-peer fashion, mobile nodes can communicate with each other by using wireless multihop communication. Due to its low cost, high flexibility, fast network establishment and self-reconfiguration, ad hoc networking has received much interest during the last ten years. However, without a fixed infrastructure, frequent path changes cause significant numbers of routing packets to discover new paths, leading to increased network congestion and transmission latency over fixed networks. Many on-demand routing protocols have been developed by using various routing mobility metrics to choose the most reliable routes, while dealing with the primary obstacle caused by node mobility. ¶ In the first part, we have developed an analysis framework for mobility metrics in random mobility model. Unlike previous research, where the mobility metrics were mostly studied by simulations, we derive the analytical expressions of mobility metrics, including link persistence, link duration, link availability, link residual time, link change rate and their path equivalents. We also show relationships between the different metrics, where they exist. Such exact expressions constitute precise mathematical relationships between network connectivity and node mobility. ¶ We further validate our analysis framework in Random Walk Mobility model (RWMM). Regarding constant or random variable node velocity, we construct the transition matrix of Markov Chain Model through the analysis of the PDF of node separation after one epoch. In addition, we present intuitive and simple expressions for the link residual time and link duration, for the RWMM, which relate them directly to the ratio between transmission range and node speed. We also illustrate the relationship between link change rate and link duration. Finally, simulation results for all mentioned mobility metrics are reported which match well the proposed analytical framework. ¶ In the second part, we investigate the mobility metric applications on caching strategies and hierarchy routing algorithm. When on-demand routing employed, stale route cache information and frequent new-route discovery in processes in MANETs generate considerable routing delay and overhead. This thesis proposes a practical route caching strategy to minimize routing delay and/or overhead by setting route cache timeout to a mobility metric, the expected path residual time. The strategy is independent of network traffic load and adapts to various non-identical link duration distributions, so it is feasible to implement in a real-time route caching scheme. Calculated results show that the routing delay achieved by the route caching scheme is only marginally more than the theoretically determined minimum. Simulation in NS-2 demonstrates that the end-to-end delay from DSR routing can be remarkably reduced by our caching scheme. By using overhead analysis model, we demonstrate that the minimum routing overhead can be achieved by increasing timeout to around twice the expected path residual time, without significant increase in routing delay. ¶ Apart from route cache, this thesis also addresses link cache strategy which has the potential to utilize route information more efficiently than a route cache scheme. Unlike some previous link cache schemes delete links at some fixed time after they enter the cache, we proposes using either the expected path duration or the link residual time as the link cache timeout. Simulation results in NS-2 show that both of the proposed link caching schemes can improve network performance in the DSR by reducing dropped data packets, latency and routing overhead, with the link residual time scheme out-performing the path duration scheme. ¶ To deal with large-scale MANETs, this thesis presents an adaptive k-hop clustering algorithm (AdpKHop), which selects clusterhead (CH) by our CH selection metrics. The proposed CH selection criteria enable that the chosen CHs are closer to the cluster centroid and more stable than other cluster members with respect to node mobility. By using merging threshold which is based on the CH selection metric, 1-hop clusters can merge to k-hop clusters, where the size of each k-hop cluster adapts to the node mobility of the chosen CH. Moreover, we propose a routing overhead analysis model for k-hop clustering algorithm, which is determined by a range of network parameters, such as link change rate (related to node mobility), node degree and cluster density. Through the overhead analysis, we show that an optimal k-hop cluster density does exist, which is independent of node mobility. Therefore, the corresponding optimal cluster merging threshold can be employed to efficiently organise k-hop clusters to achieve minimum routing overhead, which is highly desirable in large-scale networks. ¶ The work presented in this thesis provides a sound basis for future research on mobility analysis for mobile ad hoc networks, in aspects such as mobility metrics, caching strategies and k-hop clustering routing protocols.

A Mobile Ad hoc Network (MANET) is a collection of wireless mobile nodes forming a temporary network without the need for base stations or any other pre–existing network infrastructure. In a peer-to-peer fashion, mobile nodes can communicate with each other by using wireless multihop communication. Due to its low cost, high flexibility, fast network establishment and self-reconfiguration, ad hoc networking has received much interest during the last ten years. However, without a fixed infrastructure, frequent path changes cause significant numbers of routing packets to discover new paths, leading to increased network congestion and transmission latency over fixed networks. Many on-demand routing protocols have been developed by using various routing mobility metrics to choose the most reliable routes, while dealing with the primary obstacle caused by node mobility. ¶ In the first part, we have developed an analysis framework for mobility metrics in random mobility model. ... ¶ In the second part, we investigate the mobility metric applications on caching strategies and hierarchy routing algorithm. ...

Numerous research articles exist for backbone formation in wireless networks; however, they cannot be applied straightforward in cognitive radio networks (CRN) due to its peculiar characteristics. Since virtual backbone has many advantages such as reduced routing overhead, dynamic maintenance, and fast convergence speed, the authors propose a backbone formation protocol in CRN. In this chapter, a backbone formation protocol is proposed using the concept of minimum spanning tree. The protocol is based on non-iterative approach, thus leading towards limited message overhead. The proposed algorithm first forms the minimum spanning tree, and second, the nodes having more than one neighbor are connected together to form the backbone.

In mobile ad hoc networks, routing protocols are becoming more complicated and problematic. Routing in mobile ad hoc networks is multi-hop because of the limited communication range of wireless radios. Since nodes in the network can move freely and randomly, an efficient routing protocol is needed in order for such networks to be able to perform well in such an environment. In this environment the routing strategy is applied such that it is flexible enough to handle large populations and mobility and be able to minimize the use of the battery. Also it should be designed to achieve maximum packet delivery ratio. Further more, the routing protocol must perform well in terms of fast convergence, low routing delay, and low control overhead traffic. In this paper an improved implementation of the Fisheye State Routing (FSR) protocols is presented, where a new selection routing criteria that utilizes a minimum number of hops is a selection metric. The results obtained from simulation indicate that the fewer number of hops used the better and more efficient the output for packet delivery ratio was generated.

This paper proposes to use virtual backbone structure to handle control messages in ad hoc networks. This structure is effective in reducing the overhead of disseminating control information. In the first part, the approach to build the virtual backbone on the setup phase is presented. The construction of backbone is based on the Minimum Connected Dominating Set (MCDS). The novelty is in the way on finding the MCDS. A Linear Programming approach is used to build a Minimum Dominating Set (MDS). Then, a spanning tree algorithm is applied to provide the MCDS. A theoretical analysis based on probabilistic approach is developed to evaluate the size of MCDS. Different techniques of diffusion in ad hoc networks are presented and compared. The flooding technique is simple and efficient, but it is expensive in term of bandwidth consumption and causes broadcast storm problem. Simulation results show that technique using virtual backbone performs flooding and it is compared to MPR (Multipoint Relay). The second part of this paper presents a distributed procedure to maintain the backbone when the mobility of terminals is introduced. A maintenance procedure will be executed by the node which changes its position. This procedure is distributed and guarantees the node connectivity to the backbone. The authors believe that the maintenance of the backbone with small size will be more effective. Simulation results show the performance of this procedure when mobility and scalability are considered.