Routing In Multi-hop Wireless Networks Research Articles

A new on the fly energy-efficient opportunistic routing in wireless multi-hop networks

ABSTRACT Wireless channels have a broadcast nature based on which opportunistic routing protocols work. In opportunistic routing protocols, packets are forwarded by the intermediate nodes that hear their transmissions, which are called candidate forwarders. In most of these algorithms, the forwarder list is pre-determined. However, the energy-efficient selection of the forwarder list is a research topic that is not considered well. Energy Efficient OPportunistic Routing algorithm (EEOPR) is presented in this paper in which the forwarders are determined on the packets’ fly. EEOPR is a flexible method that performs the routing process locally, and the candidate forwarders are selected during the routing and for each packet. The process of the candidate nodes’ selection and their packet forwarding are managed by the Genetic algorithm according to the nodes’ remaining energy and their regions. Simulation results show that network performance is improved in EEOPR compared to ROMER and CORP-M in terms of throughput, the number of duplicate packets, and the network nodes’ residual energy.

A Low-Latency Interference Coordinated Routing for Wireless Multi-Hop Networks

Recently, there has been an increasing interest in exploiting interference cancelation to support multiple adjacent concurrent transmissions instead of avoiding interference through scheduling. In line with these efforts, this paper propose an interference coordinated routing (ICR) scheme for wireless multi-hop networks to achieve more transmission concurrence, and thus lower the end-to-end delay. The proposed ICR scheme firstly constructs an initial path by the interference-aware routing algorithm, which captures the end-to-end latency and spatial resource cost as the routing metrics. Then, to analyze the feasibility of concurrent transmission for a given link set, we consider the interference coordination and formulate the concurrent transmission of multiple links as a linear programming (LP) problem. The solution to the LP problem indicates the power allocation. Finally, a distributed guard zone based selection (GBS) algorithm is further proposed to iteratively explore the maximum feasible link set for each time slot. The selected links are simultaneously active for packet transmission with the allocated power in the current time slot, and the remaining links will be put off to the next. Simulation results confirm that ICR reduces the end-to-end delay by 9.16% to 73.82%, and promotes better transmission concurrence compared with the existing schemes.

Universal stability in multi-hop radio networks

We study stability of routing in multi-hop wireless networks in the framework of adversarial queueing. A routing algorithm consists of three components: a transmission policy to decide on immediate transmissions, a scheduling policy to select a packet to transmit, and a hearing control to coordinate transmissions with scheduling. We consider two kinds of hearing control: proactive and reactive. We compare these policies and show relationships between the wired-network adversarial model and the multi-hop radio network model. In particular, we introduce a family of scheduling policies that are universally stable when using reactive hearing control, and obtain some stability results by using regular transmission oracles. We also prove that networks in which there is at least one node with an out-degree greater than 1 are unstable when using reactive hearing control, but all directed acyclic networks are universally stable, regardless of their out-degree, if using proactive hearing control.

Link state opportunistic routing for multihop wireless networks

Enhancing the quality of service is the crucial issue of future wireless networks. In this paper, we propose a new multihop wireless routing protocol inspired by opportunistic resource allocation strategies that take into account the variability of the radio conditions due to path loss, shadowing and multipath fading. Thanks to this knowledge, our proposition dynamically adapts the selected path accross time. The adaptation is function of each link state and the amount of channel information available. This allows to improve system performance in terms of delay and throughput. This solution can be used in all multihop wireless contexts but can have a special interest in wireless coverage zone extension context. Simulation results will show that the proposed routing protocol greatly outperforms the other existing protocols such as ad-hoc on-demand distance vector, optimized link state routing and extremely opportunistic routing protocols reducing mean packet delays by more than 50% in several scenarii.

Quantum-Aided Multi-Objective Routing Optimization Using Back-Tracing-Aided Dynamic Programming

Pareto optimality is capable of striking the optimal trade-off amongst the diverse conflicting QoS requirements of routing in wireless multihop networks. However, this comes at the cost of increased complexity owing to searching through the extended multi-objective search-space. We will demonstrate that the powerful quantum-assisted dynamic programming optimization framework is capable of circumventing this problem. In this context, the so-called Evolutionary Quantum Pareto Optimization (EQPO) algorithm has been proposed, which is capable of identifying most of the optimal routes at a near-polynomial complexity versus the number of nodes. As a benefit, we improve both the the EQPO algorithm by introducing a back-tracing process. We also demonstrate that the improved algorithm, namely the Back-Tracing-Aided EQPO (BTA-EQPO) algorithm, imposes a negligible complexity overhead, while substantially improving our performance metrics, namely the relative frequency of finding all Pareto-optimal solutions and the probability that the Pareto-optimal solutions are indeed part of the optimal Pareto front

A Quantum-Search-Aided Dynamic Programming Framework for Pareto Optimal Routing in Wireless Multihop Networks

Wireless Multihop Networks (WMHNs) have to strike a trade-off among diverse and often conflicting Quality-of-Service (QoS) requirements. The resultant solutions may be included by the Pareto Front under the concept of Pareto Optimality. However, the problem of finding all the Pareto-optimal routes in WMHNs is classified as NP-hard, since the number of legitimate routes increases exponentially, as the nodes proliferate. Quantum Computing offers an attractive framework of rendering the Pareto-optimal routing problem tractable. In this context, a pair of quantum-assisted algorithms have been proposed, namely the Non-Dominated Quantum Optimization (NDQO) and the Non-Dominated Quantum Iterative Optimization (NDQIO). However, their complexity is proportional to $\sqrt{N}$, where $N$ corresponds to the total number of legitimate routes, thus still failing to find the solutions in "polynomial time". As a remedy, we devise a dynamic programming framework and propose the so-called Evolutionary Quantum Pareto Optimization (EQPO) algorithm. We analytically characterize the complexity imposed by the EQPO algorithm and demonstrate that it succeeds in solving the Pareto-optimal routing problem in polynomial time. Finally, we demonstrate by simulations that the EQPO algorithm achieves a complexity reduction, which is at least an order of magnitude, when compared to its predecessors, albeit at the cost of a modest heuristic accuracy reduction.

Distributed and Jamming-Resistant Channel Assignment and Routing for Multi-Hop Wireless Networks

We are becoming more reliant on multi-hop wireless networks (MWNs) for public safety, tactical/military, and last mile Internet communications. The architecture of an MWN can be flat , as in ad-hoc networks or hierarchical , as in mesh or sensor networks. Today, the lower cost and smaller size of radios enables multiple radios to exist in a device. Hence, simultaneous transmissions on orthogonal channels are possible, which multiplies the performance of MWNs. However, an efficient communication is only possible if every device has reliable connection. A connected MWN can be created using a meticulous channel assignment (CA) scheme that reduces congestion and interference. In addition, CA needs to handle jamming attacks. The medium access control (MAC) layer is responsible for CA related tasks. However, CA results in topology changes that affect routing decisions taken at the routing layer, which could lead to unreliable network. This strong interrelationship requires a cross-layered approach to ensure reliable connectivity. In this paper, we formulate this cross-layer problem as network-path cost optimization. Because the problem is NP-hard, we propose a dynamic and distributed heuristic CA and routing scheme that is applicable for both flat and hierarchical MWNs and that is also resistant to jamming attacks. We call it distributed jamming resilient channel assignment and routing (DJ-CAR) scheme. The performance of DJ-CAR, with that of existing schemes, is compared using an OPNET simulator.

Routing in Wireless Networks With Interferences

We consider dynamic routing in multi-hop wireless networks with adversarial traffic. The model of wireless communication incorporates interferences caused by packets' arrivals into the same node that overlap in time. We consider two classes of adversaries: balanced and unbalanced. We demonstrate that, for each routing algorithm and an unbalanced adversary, the algorithm is unstable against this adversary in some networks. We develop a routing algorithm that has bounded packet latency against each balanced adversary.

Overhead Reduction by Spatial Reusability in Multi-Hop Wireless Networks

The issue of routing in multi-hop wireless networks, to achieve high end-to-end throughput, it is difficult to find the optimal path from the source node to the destination node. Although a large number of routing protocols have been implemented to find the path with minimum transmission time for sending a single packet, such transmission time reduces protocols cannot be guaranteed to achieve high end-to-end throughput. Spatial reusability aware routing in multi hop wireless network is featured by considering spatial reusability of the wireless communication media. Spatial reusability-aware single-path routes and any path routing protocols, and compare them with existing single-path routing and any path routing protocols, respectively. Our evaluation results demonstrate that our protocols significantly improve the end-to-end throughput compared with existing protocols. Resource allocation algorithm is inquired to maximize the energy efficiency (EE) in multiuser decode-and-forward (DF) relay interference networks.

Fuzzy Logic Based Enhanced AOMDV with Link Status Classification for Efficient Multi-Path Routing in Multi-Hop Wireless Networks

Nodes in a multi-hop wireless network rely on each other to maintain network connectivity. A primary design objective of these networks is to eliminate or minimize the unavailability of network at some point. However, the movement of nodes creates service disruption and delay as path failure detection and re-establishment consume considerable amount of time. Existing solutions for link classification and prediction operate on discrete values resulting in performance degradation. This problem can best be modelled using fuzzy logic. This work presents a new fuzzy logic based link status classification mechanism for the use with multipath routing protocols in multi-hop wireless networks. The new Enhanced Adhoc On-demand Multipath Distance Vector (eAOMDV) uses fuzzy logic to classify the link status as active, about-to-break or broken. On the basis of fuzzy input parameters RSSI, velocity, distance and bit error rate, the fuzzy based classification mechanism predicts in advance that a particular link, on the active path between the sender and receiver, is about-to-break and helps the reactive multipath routing protocol to start the rerouting operation, thus minimizing the service disruption time, route discovery frequency, end-to-end delay and the packet loss.

An optimal spectrum-efficient routing protocol for multi-hop 802.11s networks

Routing in multi-hop wireless networks is a vital aspect to sustain acceptable performance. Standard routing schemes, such as ad-hoc on-demand vector routing (AODV) and dynamic source routing (DSR), use the number of hops from source to destination as the routing metric without paying attention to the physical layer properties of the wireless links. This paper, however, presents a new routing protocol for finding the path with maximum end-to-end spectral efficiency in real-world IEEE 802.11s networks. In contrast to previous work, our protocol fully considers the physical layer characteristics of the wireless channel, the interaction between network layer route computation and medium access control (MAC) contention resolution, in addition to all necessary information gathering and exchange performed by the wireless nodes. Furthermore, we provide a full NS-2 simulation comparison between spectrum-efficient routing and standard routing protocols using various performance metrics such as end-to-end data rate, delay, packet loss and overhead time.

Cluster-based Cooperative Data Forwarding with Multi-radio Multi-channel for Multi-flow Wireless Networks

Cooperative forwarding has shown a substantial network performance improvement compared to traditional routing in multi-hop wireless network. To further enhance the system throughput, especially in the presence of highly congested multiple cross traffic flows, a promising way is to incorporate the multi-radio multi-channel (MRMC) capability into cooperative forwarding. However, it requires to jointly address multiple issues. These include radio-channel assignment, routing metric computation, candidate relay set selection, candidate relay prioritization, data broadcasting over multi-radio multi-channel, and best relay selection using a coordination scheme. In this paper, we propose a simple and efficient cluster-based cooperative data forwarding (CCDF) which jointly addresses all these issues. We study the performance impact when the same candidate relay set is being used for multiple cross traffic flows in the network. The network simulation shows that the CCDF with MRMC not only retains the advantage of receiver diversity in cooperative forwarding but also minimizes the interference, which therefore further enhances the system throughput for the network with multiple cross traffic flows.

An energy-efficient cooperative multicast routing in multi-hop wireless networks for smart medical applications

With the advance of multimedia and pattern recognition based medical technologies, smart medical applications in smart hospital and smart medical for individual, such as disease diagnosis and health monitoring, play an important role in our life. However, the communication infrastructure of supporting these applications is a challenge. This paper studies the energy-efficient multicast routing problem in multi-hop wireless networks for these medical applications. Energy consumption has become the main problem of sustainable development of communication networks, particularly for these applications. How to carry out high energy-efficient communication is an important research topic for wired and wireless networks to implement green communications. This paper proposes an energy-efficient multicast routing approach to multi-hop wireless networks for smart medical applications. Different from previous methods, we aim at maximizing energy efficiency of networks. To this end, we make use of topology control and sleeping mechanism to obtain the optimal routing strategy with maximum network energy efficiency to construct the network multicast route. Simulation results show that the proposed approach is effective and feasible.

QoS-Aware Forward Error Correction Cooperating with Opportunistic Routing in Wireless Multi-hop Networks

QoS provisioning in wireless multi-hop networks is always a hot researching issue, and QoS is mainly influenced by symbol error rate and transmission delay. Conventional adaptive forward error correction and opportunistic routing cannot perceive the wireless networks' condition well for improving the QoS performance, because the transmission delay and reliability are contradictory for each other, and both of adaptive forward correction and opportunistic routing only focus on optimizing one side. In this paper, we propose QoS-aware forward error correction cooperating with opportunistic routing (QFEC-OR), which balances the reliability and effectiveness to improve QoS performance. Then we adopt a better QoS performance perception parameter--20---80 perception parameter to make QFEC-OR superior for QoS experience. We compare QFEC-OR with two kinds of encoding schemes combined with OR to illustrate QFEC-OR's efficiency, and compare QFEC-OR employing 20---80 perception parameter with two kinds of perception parameters employed in QFEC-OR to illustrate the 20---80 perception parameter makes QFEC-OR provide better QoS performance. Simulation results demonstrate the higher effectiveness of QFEC-OR with 20---80 perception parameter for QoS provisioning in wireless multi-hop networks.

Spatial Reusability-Aware Routing in Multi-Hop Wireless Networks

In the problem of routing in multi-hop wireless networks, to achieve high end-to-end throughput, it is crucial to find the “best” path from the source node to the destination node. Although a large number of routing protocols have been proposed to find the path with minimum total transmission count/time for delivering a single packet, such transmission count/time minimizing protocols cannot be guaranteed to achieve maximum end-to-end throughput. In this paper, we argue that by carefully considering spatial reusability of the wireless communication media, we can tremendously improve the end-to-end throughput in multi-hop wireless networks. To support our argument, we propose spatial reusability-aware single-path routing (SASR) and anypath routing (SAAR) protocols, and compare them with existing single-path routing and anypath routing protocols, respectively. Our evaluation results show that our protocols significantly improve the end-to-end throughput compared with existing protocols. Specifically, for single-path routing, the median throughput gain is up to 60 percent, and for each source-destination pair, the throughput gain is as high as $5.3\times$ ; for anypath routing, the maximum per-flow throughput gain is 71.6 percent, while the median gain is up to 13.2 percent.

Delay-Aware Resource Control and Routing in Multihop Wireless Networks

This letter addresses the dynamic resource control and routing problem in multihop wireless networks with time-varying channels. Subject to different per-flow end-to-end delay requirements, a new queue management policy is designed and then, a delay parameter is introduced by combining both delay constraints and path length to destination nodes. By taking advantage of the delay parameter and the queue management policy, this letter proposes a congestion control, routing and scheduling backpressure algorithm. The proposed algorithm not only approaches arbitrarily close to the optimal throughput, but also adaptively selects favorable routes according to per-flow delay constraints. Simulation results show our algorithm effectively achieves a well-performed delay performance while ensuring the throughput.

Energy Conservation Routing in Multihop Wireless Networks

Energy conservation is a central issue in the design of a wireless mesh network powered by solar cells. Since traffic uncertainty is always present, in this paper, we study how to design an energy-conservation routing scheme in face of traffic uncertainty. We present a new approach that is immune from the two problems prevalent in conventional approaches: performance degradation caused by inaccuracy of a simplified interference model and the instability caused by the assumption of unbounded transmission power and data rate. The analytical and simulation results presented in this paper show that the proposed approach can achieve significant performance gains, in terms of throughput and energy consumption, over the conventional approach.

Mathematical Modeling and Analysis Methodology for Opportunistic Routing in Wireless Multihop Networks

Modeling the forwarding feature and analyzing the performance theoretically for opportunistic routing in wireless multihop network are of great challenge. To address this issue, a generalized geometric distribution (GGD) is firstly proposed. Based on the GGD, the forwarding probability between any two forwarding candidates could be calculated and it can be proved that the successful delivery rate after several transmissions of forwarding candidates is irrelevant to the priority rule. Then, a discrete-time queuing model is proposed to analyze mean end-to-end delay (MED) of a regular opportunistic routing with the knowledge of the forwarding probability. By deriving the steady-state joint generating function of the queue length distribution, MED for directly connected networks and some special cases of nondirectly connected networks could be ultimately determined. Besides, an approximation approach is proposed to assess MED for the general cases in the nondirectly connected networks. By comparing with a large number of simulation results, the rationality of the analysis is validated. Both the analysis and simulation results show that MED varies with the number of forwarding candidates, especially when it comes to connected networks; MED increases more rapidly than that in nondirectly connected networks with the increase of the number of forwarding candidates.

Non-Dominated Quantum Iterative Routing Optimization for Wireless Multihop Networks

Routing in wireless multihop networks (WMHNs) relies on a delicate balance of diverse and often conflicting parameters, when aiming for maximizing the WMHN performance. Classified as a non-deterministic polynomial-time hard problem, routing in WMHNs requires sophisticated methods. As a benefit of observing numerous variables in parallel, quantum computing offers a promising range of algorithms for complexity reduction by exploiting the principle of quantum parallelism (QP), while achieving the optimum full-search-based performance. In fact, the so-called non-dominated quantum optimization (NDQO) algorithm has been proposed for addressing the multiobjective routing problem with the goal of achieving a near-optimal performance, while imposing a complexity of the order of $O(N)$ and $O(N\sqrt {N})$ in the best and worst case scenarios, respectively. However, as the number of nodes in the WMHN increases, the total number of routes increases exponentially, making its employment infeasible despite the complexity reduction offered. Therefore, we propose a novel optimal quantum-assisted algorithm, namely, the non-dominated quantum iterative optimization (NDQIO) algorithm, which exploits the synergy between the hardware and the QP for the sake of achieving a further complexity reduction, which is on the order of $O(\sqrt {N})$ and $O(N\sqrt {N})$ in the best and worst case scenarios, respectively. In addition, we provide simulation results for demonstrating that our NDQIO algorithm achieves an average complexity reduction of almost an order of magnitude compared with the near-optimal NDQO algorithm, while having the same order of power consumption.

Effective Cluster based Routing Algorithm for WMNS using Effective Data Aggregation

Wireless Mesh Network (WMN) is a key technology, supporting a variety of several emerging and commercially interesting applications. The multi-hop nature of WMNs and the rapid growth of throughput demands lead to multichannels and multi-radios structures in mesh networks, but the interference of co-channels, as a main problem reduces the total throughput, especially in multi-hop networks. QoS (Quality of Service) refers to a vast collection of networking technologies and techniques that guarantees the ability of a network to provide with predictable results. Due to interference among various transmissions, the QoS routing in multi-hop wireless networks is formidable task. In case of multi-channel wireless network, since two transmissions using the same channel may get in with each other so there exists interference. The request of QoS connection usually accompanies bandwidth requirement and QoS routing seeks a source to destination route with requested bandwidth. The main objectives of QoS based routing are optimal utilization of resources for improving total network throughput and graceful performance degradation during overloading conditions offering better throughput, Dynamic determination of feasible paths for accommodating the QoS of the given flow under various policy constraints such as provider selection, path cost etc. The overall objective of this paper is to propose a new multi-radio, multi-channel and clustering based wireless mesh protocol to improve the QoS further. This paper has considered the DSDV protocol to locate the secure and optimized path. The proposed technique also utilizes the LZW based lossless data compression and intra cluster data aggregation to enhance the communication between the source and the destination. The use of clustering has the ability to aggregates the multiple packets and locate a single route using the clusters to improves the intra cluster data aggregation. The use of the LZW based loss less data compression has ability to reduce the data packet size so will consume lesser energy thus increase the network QoS. The MATLAB tool has been used to evaluate the effectiveness of the proposed technique. the comparative analysis has shown that the proposed technique outperforms over the available techniques.