Performance Evaluation of Multi-Channel Wireless Mesh Networks with Embedded Systems

Many commercial wireless mesh network (WMN) products are available in the marketplace with their own proprietary standards, but interoperability among the different vendors is not possible. Open source communities have their own WMN implementation in accordance with the IEEE 802.11s draft standard, Linux open80211s project and FreeBSD WMN implementation. While some studies have focused on the test bed of WMNs based on the open80211s project, none are based on the FreeBSD. In this paper, we built an embedded system using the FreeBSD WMN implementation that utilizes two channels and evaluated its performance. This implementation allows the legacy system to connect to the WMN independent of the type of platform and distributes the load between the two non-overlapping channels. One channel is used for the backhaul connection and the other one is used to connect to the stations to wireless mesh network. By using the power efficient 802.11 technology, this device can also be used as a gateway for the wireless sensor network (WSN)

Performance study of Hybrid Wireless Mesh Protocol(HWMP) for IEEE 802.11s WLAN Mesh Networks

Wireless Mesh Network (WMN) have been envisioned as an important solution to the next generation wireless networking which can be used in wireless community networks, wireless enterprise networks, transportation systems, home networking and last-mile wireless internet access. Many proprietary mesh solutions were developed by individual vendor but in order to interoperability; IEEE forms a task group called IEEE 802.11s to develop an integrated mesh networking solution. Hybrid Wireless Mesh protocol (HWMP) and airtime metrics as default routing protocol and routing metrics set by the task group. There is few test bed and many simulation studies have been done to evaluate the performance of the HWMP protocol with the assumption of unique type of flow with fixed packet size and packet rate. However, real networks carry a diverse application (video, voice, FTP, Email etc) with different characteristics (packet size, data rate). In this paper, we are investigated and analyzed the performance of HWMP protocol under such heterogeneous application characteristics

Traffic engineering multi-layer optimization for wireless mesh network transmission a campus network routing protocol transmission performance inhancement

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel UniversityThe wireless mesh network is a potential network for the future due to its excellent inherent characteristic for dynamic self-healing, self-configuration and self-organization. It also has the advantage of easy interoperability networking and the ability to form multi-linked ad-hoc networks. It has a decentralized topology, is cheap and highly scalable. Furthermore, its ease in deployment and easy maintenance are other inherent networking qualities. These aforementioned qualities of the wireless mesh network bring advantages to transmission capability of heterogeneous networks. However, transmissions in wireless mesh network create comparative performance based challenges such as congestion, load-balancing, scalability over increasing networks and coverage capacity. Consequently, these challenges and problems in the routing and switching of packets in the wireless mesh network routing protocols led to a proposal on the resolution of these failures with a combination algorithm and a management based security for the network and its transmitted packets. There are equally contentious services like reliability of the network and quality of service for real-time multimedia traffic flows with other challenges such as path computation and selection in the wireless mesh network. This thesis is therefore a cumulative proposal to the resolution of the outlined challenges and open research areas posed by using wireless mesh network routing protocol. It advances the resolution of these challenges in the mesh environment using a hybrid optimization – traffic engineering, to increase the effectiveness and the reliability of the network. It also proffers a cumulative resolution of the diverse contributions on wireless mesh network routing protocol and transmission. Adaptation and optimization are carried out on the wireless mesh network designed network using traffic engineering mechanism and technique. The research examines the patterns of mesh packet transmission and evaluates the challenges and failures in the mesh network packet transmission. It develops a solution based algorithm for resolutions and proposes the traffic engineering based solution.. These resultant performances and analysis are usually tested and compared over wireless mesh IEEE802.11n or other older proposed documented solution. This thesis used a carefully designed campus mesh network to show a comparative evaluation of an optimal performance of the mesh nodes and routers over a normal IEE802.11n based wireless domain network to show differentiation by optimization using the created algorithms. Furthermore, the indexes of performance being the metric are used to measure the utility and the reliability, including capacity and throughput at the destination during traffic engineered transmission. In addition, the security of these transmitted data and packets are optimized under a traffic engineered technique. Finally, this thesis offers an understanding to the security contribution using traffic engineering resolution to create a management algorithm for processing and computation of the wireless mesh networks security needs. The results of this thesis confirmed, completed and extended the existing predictions with real measurement

Load Balancing Dynamic Source Routing Protocol Based on Multi-Path Routing

A HWMP improved routing protocol (HWMMRP) is proposed in this paper. The protocol adopts the integrated link state routing criterion algorithm LCCM providing small overhead, with factors such as bandwidth, queue length and noise interference fully considered. In order to solve the problem of the tree routing mechanism being easily congested at the root node, a multi-path multi-gateway shunting mechanism is applied. A multipath routing mechanism is also incorporated in the reactive routing mode. Both the new criteria and the protocol are simulated in the NS-2 environment, and are compared with comparable protocols. The experimental results show that our protocol can effectively avoid node congestion, and provides a better dynamic load balancing capability as well as a better performance than the standard HWMP and AODV protocols

On the Benefits of a Cooperative Layer-2 based Routing Approach for Hybrid Wireless Mesh Networks

In a wireless mesh network, the convenience of a routing strategy strongly depends on the mobility of the intermediate nodes that compose the paths. Taking into account this behavior, this paper presents a routing scheme that works differently accordingly to the nodes mobility. In this sense, a proactive routing scheme is restricted to the backbone in order to promote the use of stable routes. On the other hand, the reactive protocol is used to search routes to or from a mobile destination. Both approaches are simultaneously implemented in the mesh nodes so that the routing protocols share routing information that optimize the network performance. Aiming at guaranteeing the IP compatibility, the combination of the two protocols in the core routers is carried out at the Medium Access Control (MAC) layer. Opposite to the operation at IP layer where two routing protocols are not able to concurrently work, the transfer of the routing tasks to the MAC layer enables the use of multiple independent forwarding tables. Simulation results show the goodness of the proposal in terms of packet losses and data delayTriviño, A.; Ariza, A.; Casilari, E.; Cano Escribá, JC. (2013). On the Benefits of a Cooperative Layer-2 based Routing Approach for Hybrid Wireless Mesh Networks. China Communications. 10(8):88-99. doi:10.1109/CC.2013.6633748S889910

Security and Privacy Issues in Wireless Mesh Networks: A Survey

This book chapter identifies various security threats in wireless mesh network (WMN). Keeping in mind the critical requirement of security and user privacy in WMNs, this chapter provides a comprehensive overview of various possible attacks on different layers of the communication protocol stack for WMNs and their corresponding defense mechanisms. First, it identifies the security vulnerabilities in the physical, link, network, transport, application layers. Furthermore, various possible attacks on the key management protocols, user authentication and access control protocols, and user privacy preservation protocols are presented. After enumerating various possible attacks, the chapter provides a detailed discussion on various existing security mechanisms and protocols to defend against and wherever possible prevent the possible attacks. Comparative analyses are also presented on the security schemes with regards to the cryptographic schemes used, key management strategies deployed, use of any trusted third party, computation and communication overhead involved etc. The chapter then presents a brief discussion on various trust management approaches for WMNs since trust and reputation-based schemes are increasingly becoming popular for enforcing security in wireless networks. A number of open problems in security and privacy issues for WMNs are subsequently discussed before the chapter is finally concluded.Comment: 62 pages, 12 figures, 6 tables. This chapter is an extension of the author's previous submission in arXiv submission: arXiv:1102.1226. There are some text overlaps with the previous submissio

An Optimization Framework for IEEE 802.11s Based Wireless Mesh Network

Wireless mesh network (WMN) is a promising area of research. Energy efficiency in WMN can play vital role in achieving green wireless communication. This research work considers IEEE 802.11s link based power saving modes. Energy aware joint optimization of routing, link scheduling under wireless interference and delay constraint has been considered. For given traffic load a model has been formulated to minimize network energy consumption by choosing optimum power saving mode for peer links. It is stressed that redundant links and nodes can be turned in low power state for energy savings

Layer 2 Path Selection Protocol for Wireless Mesh Networks with Smart Antennas

In this thesis the possibilities of smart antenna systems in wireless mesh networks are examined. With respect to the individual smart antenna tradeoffs, a routing protocol (Modified HWMP, MHWMP) for IEEE 802.11s mesh networks is presented, that exploits the full range of benefits provided by smart antennas: MHWMP actively switches between the PHY-layer transmission/reception modes (multiplexing, beamforming and diversity) according to the wireless channel conditions. Spatial multiplexing and beamforming are used for unicast data transmissions, while antenna diversity is employed for efficient broadcasts. To adapt to the directional channel environment and to take full benefit of the PHY capabilities, a respective MAC scheme is employed. The presented protocol is tested in extensive simulation and the results are examined.:1 Introduction 2 Wireless Mesh Networks 3 IEEE 802.11s 4 Smart Antenna Concepts 5 State of the Art: Wireless Mesh Networks with Smart Antennas 6 New Concepts 7 System Model 8 Results and Discussion 9 Conclusion and Future Wor

Cross Layer Design to Reduce the Latency for Effective Scheduling Technique for Mobile Ad hoc Networks

Wireless Mesh Networking (WMN) technology provides a key revolutionary to the future backbone network access. WMN adopt a multihop based transmission to improve end to end data delivery. The 802.11s MAC (Medium Access Control) is designed using CSMA (Carrier Sense Medium Access) protocol which result in collision of slot due to failure in detecting hidden node in WMN. Various methodologies have been developed to optimize the MAC and hidden node and exposed node detection algorithm in recent time to utilize slot efficiently and reduce latency. Slot reutilization is an effective way in reducing latency but due to improper detection of hidden node of existing algorithm the latency is increased. To overcome this, our work propose an efficient device classification based MAC scheduler by adopting a cross layer design to reduce the latency. The experiment are conducted by varying network size and density and the outcome shows that the proposed approach perform better than existing CSMA/OCA in term of latency