Multi-radio Wireless Mesh Networks Research Articles

Optimizing Interference Management in Multi-Channel Multi-Radio Wireless Mesh Networks

Wireless Mesh Networks (WMNs) face challenges in load balancing due to high traffic volumes. Unequal load distribution stems from two main factors: the dispersed nature of clients and their varying demands. The primary goal is to develop multi-frequency hybrid radio network systems with dynamic frequency allocation and gateway selection. A framework termed "LACE - Load-Aware Frequency Estimation" is introduced to enhance network protection, lifespan, and quality while reducing packet loss, latency, energy consumption, and routing overhead. This approach facilitates the expansion of coverage without compromising frequency capacity by enabling dynamic frequency allocation and gateway selection in WMNs.

Localized Network Reconfiguration Plan for Wireless Mesh Networks

Abstract: Wireless mesh networks (WMNs) have emerged as a key technology for next-generation wireless networking. Because of their advantages over other wireless networks, WMNs are undergoing rapid progress and inspiring numerous applications. In multi-hop wireless mesh networks (WMNs) experience frequent link failures caused by channel interference, dynamic obstacles and/or applications’ bandwidth demands. These failures cause severe performance degradation in WMNs or require expensive, manual network management for their real-time recovery. This paper presents an Autonomous network Reconfiguration System (ARS) that enables a multi-radio WMN to autonomously recover from local link failures to preserve network performance. ARS also improves channel efficiency by more than 90% over the other recovery methods. During their lifetime, multi-hop wireless mesh networks (WMNs) experience frequent link failures caused by channel interference, dynamic obstacles, and/or applications’ bandwidth demands. These failures cause severe performance degradation in WMNs or require expensive manual network management for their real-time recovery. By using channel and radio diversities in WMNs, ARS generates necessary changes in local radio and channel assignments in order to recover from failures. Next, based on the thus-generated configuration changes, the system cooperatively reconfigures network settings among local mesh routers. ARS has been evaluated extensively through ns2-based simulation. Our evaluation results show that ARS outperforms existing failure-recovery schemes in improving channel-efficiency by more than 90% and in the ability of meeting the applications’ bandwidth demands by an average of 200%. Keywords: WMN, ARS, AODV, WCETT, ETT, RSVP, DSDV, ETX, ETOPE, BLC

Routing for capacity improvement in Multi-Channel-Width Multi-Radio Wireless Mesh Networks

This study indicates that the assignment of multiple channels with different bandwidths to links of a IEEE 802.11 wireless mesh network can drastically increase the capacity of these networks considering equal amount of available spectrum. However, this is possible only for networks where routers are equipped with multiple radios. In this context, this paper proposes a metric used to select the amount of radios and width of the channels to be used in each link, as well the routing path that enables a decrease in the interference between those links. We use simulations in ns-2 to assess the proposed routing metric and compare it with others in the literature. The obtained results point to an increase in the capacity of the studied networks.

An Efficient Interference Aware Partially Overlapping Channel Assignment and Routing in Wireless Mesh Networks

In recent years, multi-channel multi-radio wireless mesh networks are considered a reliable and cost effective way for internet access in wide area. A major research challenge in this network is, selecting a least interference channel from the available channels, efficiently assigning a radio to the selected channel, and routing packets through the least interference path. Many algorithms and methods have been developed for channel assignment to maximize the network throughput using orthogonal channels. Recent research and test-bed experiments have proved that POC (Partially Overlapped Channels) based channel assignment allows significantly more flexibility in wireless spectrum sharing. In this paper, first we represent the channel assignment as a graph edge coloring problem using POC. The signal-to-noise plus interference ratio is measured to avoid interference from neighbouring transmissions, when a channel is assigned to the link. Second we propose a new routing metric called signal-to-noise plus interference ratio (SINR) value which measures interference in each link and routing algorithm works based on the interference information. The simulation results show that the channel assignment and interference aware routing algorithm, proposed in this paper, improves the network throughput and performance.

Impact Of Load Balancing Interference Routing Metric On Multi Channel Multi Radio Wireless Mesh Network

Wireless Mesh Network (WMNs) is a promising technology that has been accepted favorably by the Internet Service Providers (ISPs). ISPs use it to provide last mile broadband Internet connectivity to the end users. This popularity arises from the fact, that it inter operates well with diverse wireless systems and provides robust fault tolerance with a high degree of redundancy and reliability. Routing metrics plays a crucial part in the performance of WMN. When routing protocols are implemented, the routing metric is assigned to different paths. It calculates the optimum path to predict the best routing path. These are integrated in routing protocols to improve WMNs efficiency in terms of reliability, latency, throughput, error rate and cost. This paper compares the impact of using load balancing interference aware routing metric (LBIARM) on the performance of Multi-Channel Multi Radio WMNs (MCMR WMNs). The performance of LBIARM was evaluated by comparing it with popular standard metrics weighted cumulative expected transmission time metric and Hop Count metric. OPNET Modeler 17.5 PL1 was used as a simulation tool for implementation. Simulation results show the effectiveness of using LBIARM metric on MCMR WMNs.

Robust Beamforming Design for SWIPT-Based Multi-Radio Wireless Mesh Network with Cooperative Jamming

Wireless mesh networks (WMNs) can provide flexible wireless connections in a smart city, internet of things (IoT), and device-to-device (D2D) communications. The performance of WMNs can be greatly enhanced by adopting a multi-radio technique, which enables a node to communicate with more nodes simultaneously. However, multi-radio WMNs face two main challenges, namely, energy consumption and physical layer secrecy. In this paper, both simultaneous wireless information and power transfer (SWIPT) and cooperative jamming technologies were adopted to overcome these two problems. We designed the SWIPT and cooperative jamming scheme, minimizing the total transmission power by properly selecting beamforming vectors of the WMN nodes and jammer to satisfy the individual signal-to-interference-plus-noise ratio (SINR) and energy harvesting (EH) constrains. Especially, we considered the channel estimate error caused by the imperfect channel state information. The SINR of eavesdropper (Eve) was suppressed to protect the secrecy of WMN nodes. Due to the fractional form, the problem was proved to be non-convex. We developed a tractable algorithm by transforming it into a convex one, utilizing semi-definite programming (SDP) relaxation and S-procedure methods. The simulation results validated the effectiveness of the proposed algorithm compared with the non-robust design.

Resource Allocation for Hybrid RF/FSO Multi-Channel Multi-Radio Wireless Mesh Networks

The overwhelming data rates in next generation wireless networks impose a burden on the high-capacity network planning. One promising strategy to meet the demand for high-capacity communications is to augment radio frequency (RF) based multi-channel multi-radio (MCMR) wireless mesh network (WMN) by free-space optics (FSO). In this paper, we construct a hybrid RF/FSO MCMR WMN topology and address its resource allocation (RA) problem in terms of interface assignment, channel allocation, routing, FSO link allocation, and topology control. Considering the weather effects on FSO link availability and the fading nature of RF links, the RA problem is formulated as a two-stage optimization problem with the objective of maximizing the network throughput. In our optimization model, we formulate each stage as a mixed integer linear program, and the bottleneck RF links are gradually upgraded by FSO links. To avoid the computational complexity of the second stage optimization, an improved iterated local search algorithm is proposed. Simulation results show that our RA scheme is efficient and the throughput can be enhanced dramatically by proper FSO link augmentation.

Cross-layer Optimization for Video Transmission using MDC in Wireless Mesh Networks

Abstract In this paper, we propose a cross-layer optimization technique for improving the QoS of video streaming applications in multi-radio Wireless Mesh Networks (WMNs) using Multiple Description Coding (MDC). WMN is an emerging technology which is used to connect various types of networks to the internet. As the trafficdensity is very high fromthe client mesh to the gateways, load balancing in these networks has become an important research issue. Thus, there is a need for multipath routing which can exploit the multi-radio capabilities along with the load balancing mechanism. Furthermore, the dynamic and shared nature of wireless medium makes the task of supporting QoS for video streaming applications challenging. Towards this,MDCis an effective technique for the video transmission over the unpredictable routes because of varying channel conditions.In this work,we compute multiple paths using Passive Interference andDelay Aware (PIDA) metric and performload balancing using MDC. Proposed work is implemented in Ad hoc On-demand Multipath Distance Vector (AOMDV) routing protocol using NS2 simulator. The results reveal that proposed technique withMDCperforms better in terms of PSNR, frame delay and frame loss compared to existing technique

Traffic-Demand-Aware Collision-Free Channel Assignment for Multi-Channel Multi-Radio Wireless Mesh Networks

In multi-channel multi-radio wireless mesh networks (MCMR WMNs), assigning each radio with an appropriate channel to maximize the performance is a challenging problem. In this optimization, the primal concern lays on how to mitigate effects of interference to avoid performance degradation. However, collision-freedom for a given traffic demand under the limitation of precious channel resources has not been achieved yet. In this paper, we present a collision-free joint channel assignment and routing scheme called TACCA (Traffic-demand-Aware Collision-free Channel Assignment) for MCMR WMNs. To reduce the required number of channels, TACCA incorporates a property of CSMA (Carrier Sense Multiple Access), i.e., it adopts CSMA-aware interference model and a CSMA-aware shared link capacity model. We formulate a mixed integer linear programming (MILP) to optimize the network utility and enhance the practical usefulness under the given traffic demands. The evaluation results with a MILP solver show that TACCA achieves collision-freedom in both grid and random topology networks with 3-5 orthogonal channels, and exhibits good network utilization performance. In addition, the network simulation results show that TACCA achieves mostly collision-free communications under up-to-date PHY and MAC models, and presents excellent communication performance.

Multi Rate Multicast Routing in Fixed Gateway Multi Channel and Multi Radio Wireless Mesh Network

WMN is the wireless mesh network is having real type of application in the current time for the multicasting type of networking. Where one sender and there is a group of people who receives the message. But the bandwidth constraints will make the network to be on the slower side because the lowest speed channel will be allotted to the receiver automatically. The proposed algorithm with fixed gateway position with multichannel and multi radio wireless mesh network can create efficiency into the network. The proposed algorithm is having ability to get maximum throughput with the balancing of the different gateways with multichannel and multi radio wireless mesh network. The proposed algorithm has been tested in node count of 15 and 30 with variable channel and with variable number of receivers. The performance of the network is enhanced compared to the MGMR with variable number of gateway. Optimization based technique if applied for the identification of the optimal node. The simulated results are optimal in all the scenarios.

Online multicast tree construction with bandwidth and delay constraints in multi-channel multi-radio wireless mesh networks

This paper deals with online QoS multicast tree construction problem, which is essential to support multimedia services, in multi-channel multi-radio wireless mesh networks. The proposed algorithm satisfies both delay and bandwidth requirements of each arrived session. It breaks down the original problem into two phases of satisfying delay and bandwidth constraints. The first phase devotes to preserving delay constraint of the arrived session, in which a number of delay-bounded paths are determined between each receiver and the source node. In the proposed scheme, to diminish the utilized bandwidth, the overlapping of the regarding paths of the receivers is maximized as much as possible. We propose a mathematical model to satisfy bandwidth requirement in the second phase, which constructs the tree over the selected paths. The data transmission rate on the tree is set to the requested rate by the session, to satisfy its bandwidth requirement. The proposed model has a global view over the network and constructs the most appropriate trees. It also exploits wireless broadcast advantage property to enhance the performance. Through extensive simulations, the effectiveness of the proposed algorithm is verified. In particular, it improves the acceptance rate by 60% compared to previous schemes.

Online network coding-based multicast routing in multichannel multiradio wireless mesh networks

In this paper, we consider the problem of online multicast routing in multichannel multiradio wireless mesh networks (WMNs). We propose an efficient online algorithm, namely zone-based multicast routing (ZBMR), which exploits network coding and wireless broadcast advantage. In the proposed algorithm, to investigate the acceptance of an arrived session in polynomial time, the WMN is divided into some zones. The derived zones are processed sequentially, where the zone processing is defined as connecting the receivers in a given zone to the session. The main challenge in this scheme is to enable data transmission to the receivers in each zone. If a zone does not contain the source node, it should obtain data from the previously processed neighboring zones. The problem is that the data transmission fails if there is no receiver on the common border between the considered zone and its processed neighboring zones. Our solution to tackle this challenge is to add some virtual receivers to the borders of the zones. The extensive simulations show that ZBMR increases the acceptance rate by 50% in comparison to the previous approaches.

A dynamic channel assignment method for multichannel multiradio wireless mesh networks

The popularity of wireless communication accelerates research on new technologies that are required to satisfy users' needs. Wireless mesh networks (WMNs), which are additional access technologies instead of being a renewed one, have an important place among next-generation wireless networks. In particular, the capability of working without any infrastructure is the most outstanding advantage of WMNs. There are many studies aimed at WMNs, particularly channel assignment and routing methods for multichannel multiradio structures that provide higher data capacity. Interference, which has a direct effect on the quality of communication, is still a challenge to be addressed. In this study, multichannel multiradio WMNs and various channel assignment schemes are analyzed. Directional mesh (DMesh) architecture, which uses directional antennas to form a multichannel structure, is analyzed in terms of channel assignment procedure. A new interference-aware channel assignment scheme that aims to eliminate DMesh's disadvantages is proposed and performances of both schemes are compared. Several results of experimental analysis prove that the proposed channel assignment scheme improves the performance of DMesh

Interference Aware, Topology, Power and Flow Control Channel Assignment Algorithm for Multi-Radio Multi-Channel Wireless Mesh Networks

Interference Aware, Topology, Power and Flow Control Channel Assignment Algorithm for Multi-Radio Multi-Channel Wireless Mesh Networks

A cross-layer interference and delay-aware routing metric for multi-radio infrastructure wireless mesh networks

In this paper, we propose new cross-layer interference and delay aware (CL-IDA) routing metric for multi-radio infrastructure wireless mesh networks (WMNs). WMNs use multichannel multiple radio (MCMR) capabilities of mesh routers to achieve high performance. However, QoS degrades significantly due to inter-flow and intra-flow interference as the number of hops and radio interfaces increase. Thus, design of routing protocols combined with routing metrics to improve QoS has become an important research issue. The routing metrics proposed in the literature have their own disadvantages and lack the analytical model in their design. Towards this, we design and implement CL-IDA metric based on the analytical model by estimating delay, inter-flow and intra-flow interference using cross-layer information. We implement this metric using optimised link state routing (OLSR) protocol in NS2. The results reveal that, CL-IDA metric performs better in terms of throughput and average delay compared to well known routing metrics.

Load-aware multicast routing in multi-radio wireless mesh networks using FCA-CMAC neural network

Multicasting is a useful network service in wireless mesh networks (WMNs) for delivering same data from a source to multiple destinations. An effective multicast routing protocol in multi-channel multi-radio WMNs (MCMR-WMNs) is required to satisfy the following criteria together: high network throughput, low end-to-end delay, low tree cost, low computational time, and load-aware routing. Furthermore, how to fully exploit channel diversity in MCMR-WMNs to accomplish low channel interference criteria is a critical issue in designing multicast routing protocol. In spite of its significance, multicast routing which satisfies all of the mentioned criteria, has not drawn much attention so far. Besides, major multicast routing protocols proposed in MCMR-WMNs are centralized or solve two problems of multicast tree construction and channel assignment sequentially. These protocols are time-consuming in addition to suffering from a single-point-of-failure. In this paper, we propose a distributed cross-layer algorithm for joint multicast routing and channel assignment in MCMR-WMNs. For the first time, we apply fuzzy credit assigned cerebellum model articulation controller (FCA-CMAC) neural network model to construct multicast routing tree considering load on the mesh nodes and the delay between neighboring mesh nodes. Moreover, we present a heuristic channel assignment algorithm aiming to reduce interference among the links of the multicast tree. FCA-CMAC converges quickly and creates minimal delay and load-aware multicast tree. Therefore, proposed method can optimize the network throughput, end-to-end delay, tree cost, and computational time. Additionally, channel assignment algorithm is subject to produce the minimal interference multicast tree. Simulation results show that in terms of aforementioned criteria, the proposed FCA-CMAC based multicast algorithm achieves better performance than those comparative references.

A joint approach to routing metrics and application-aware rate adaptation in multi-radio wireless mesh networks

A joint approach to routing metrics and application-aware rate adaptation in multi-radio wireless mesh networks

Q-CAR: an intelligent solution for joint QoS multicast routing and channel assignment in multichannel multiradio wireless mesh networks

Multicast routing improves the efficiency of a network by effectively utilizing the available network bandwidth. In multichannel multiradio wireless mesh networks the channel allocation strategy plays a vital role along with multicast tree construction. However, the multicast routing problem in multichannel multiradio wireless mesh networks is proven to be NP-hard. With this paper, we propose a Quality of Service Channel Assignment and multicast Routing (Q-CAR) algorithm. The proposed algorithm jointly solves the channel assignment and multicast tree construction problem by intelligent computational methods. We use a slightly modified differential evolution approach for assigning channels to links. We design a genetic algorithm based multicast tree construction strategy which determines a delay, jitter bounded low cost multicast tree. Moreover, we define a multi objective fitness function for the tree construction algorithm which optimizes interference as well as tree cost. Finally, we compare the performance of Q-CAR with QoS Multicast Routing and Channel Assignment(QoS-MRCA) and intelligent Quality of service multicast routing and Channel Assignment(i-QCA) algorithm in multichannel multiradio wireless mesh network (simulated) environments. Our experimental results distinctly show the outstanding performance of the proposed algorithm.

A joint routing and channel assignment in multi-radio multi-channel wireless mesh networks

To reduce inter-link interference and balance networks loads, this paper presents and evaluates a cross-layer algorithm for multi-radio multi-channel wireless mesh networks (WMNs), while conducting routing channel assignments. In channel assignment phase, we propose a greedy algorithm based on a multi-radio multi-channel interference model and select the channel with minimum of interference degree. In the routing phase, a new routing parameter which comprehensively considers interference, delay, load balancing and other factors is proposed. The new algorithm is compared with existing algorithm that is multi-radio multi-channel WMN based on ad hoc on-demand distance vector routing (MRMC-AODV) to illustrate the advantages. When the load reaches 6 Mbps, the throughput exceeds 14% of the MRMC-AODV, with a delay of nearly 80% of the MRMC-AODV latency and it reduces packet loss ratio by about 12%. The simulation results show that this algorithm can effectively improve the network throughput, reduce delay and decrease packet loss ratio.

Multicast Routing with Load Balancing in Multi-Channel Multi-Radio Wireless Mesh Networks

By an increasing expansion of multimedia services and group communication applications, the need for multicast routing to respond to multicast requests in wireless mesh networks is felt more than before. One of the main challenges in multi-channel multi-radio wireless mesh networks is the efficient use of the capacity of channels as well as load balance in network. In this paper, we proposed an algorithm for building a multicast tree, namely, Load balanced Multicast routing with Genetic Algorithm (LM-GA). The purpose of this algorithm is to construct a multicast tree for requested sessions in Multi-Radio Multi-Channel Wireless Mesh Networks (MCMR WMNs) regarding load balance in channels through minimizing the maximum amount of channels utilization. The results show the efficiency of LM-GA in distribution of load in the channels of the network with finding near-optimal solutions, and also an increase in the network performance while avoiding creation of bottlenecks.