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- Challenges and Issues in Designing Architectures and Protocols for Wireless Mesh Networks
- Wireless Mesh Networks: Architectures and Protocols
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Challenges and Issues in Designing Architectures and Protocols for Wireless Mesh Networks
The persistent driving force in the development of wireless mesh networks comes from their envisioned advantages including extended coverage, robustness, self- configuration, easy maintenance, and low cost.
In spite of the high attention and the massive efforts on research and development, wireless mesh networks have not yet witnessed mass market deployment. To promote the deployment of wireless mesh networks and enhance their usage, many research challenges should be considered. In this paper, we describe the possible architectures for wireless mesh networks giving a practical view on the usage scenarios and applications to turn wireless mesh networks into commodity.
Furthermore, we present some technical challenges, from an industrial practice, for the deployment of wireless mesh networks and we highlight the open research issues in this field. Jaydip Sen guidance, keen and sustained interest, intuitive ideas and persistent endeavor. His inspiring assistance, laconic reciprocation and affectionate care enabled us to work smoothly and successfully till date.
I am also thankful to Mr. Ranjit Kumar Behera, Btech project coordinator for giving his valuable time and support during the preparation of this project. I acknowledge with immense pleasure the sustained interest, encouraging attitude and constant inspiration rendered by Prof. Sangram Muduli, Director, N.
His continued drive for better quality in everything that happened at N. T and selfless inspiration has always helped us to move ahead. Unlike traditional Wi-Fi networks, with each access point AP connected to the wired network, in WMNs only a subset of the APs are required to be connected to the wired network.
The IGWs provide access to conventional clients and interconnect ad hoc, sensor, cellular, and other networks to the Internet as shown in Fig. Fig 1. The latter offers connectivity to the former by acting like APs, forming at the same time a self-organized wireless backbone. This backbone has two possible roles.
It can be either a standalone network simply offering inter- client connectivity or a local extension for the wired Internet if there are available connections between one or more WMRs gateways. This characteristic, coupled with the other advantages such as reduction in deployment cost, connecting hard-to-wire areas, resilience, self organization and self healing behaviour and the extensibility make the WMN architecture very appealing to network operators and service providers.
Mesh networking is a very interesting next generation wireless paradigm which is extensively discussed in this article considering the network operator's perspective. The emergence of new wireless access technologies and standards like These aspects have generated interests towards a wide variety of potential applications and usage scenarios for the mesh networking domain. However, there are various practical issues, particularly relating to performance, quality of service, security, network management and monitoring, scalability etc.
Compared with a conventional wireless router, a wireless mesh router can achieve the same coverage with much lower transmission power through multi-hop communications. Optionally, the medium access control MAC protocol in a mesh router is enhanced with better scalability in a multi-hop mesh environment. The architecture of WMNs can be classified into three main groups based on the functionality of the nodes: 3.
This type of WMNs includes mesh routers forming an infrastructure for clients that connect to them. The mesh routers form a mesh of self-configuring, self-healing links among themselves. With gateway functionality, mesh routers can be connected to the Internet. Conventional clients with Ethernet interface can be connected to mesh routers via Ethernet links. For conventional clients with the same radio technologies as mesh routers, they can directly communicate with mesh routers.
For example, community and neighborhood networks can be built using infrastructure meshing. The mesh routers are placed on the roof of houses in a neighborhood, which serve as access points for users inside the homes and along the roads. Typically, two types of radios are used in the routers, i. The mesh backbone communication can be established using long-range communication techniques including directional antennas. Fig 2. In this type of architecture, client nodes constitute the actual network to perform routing and configuration functionalities as well as providing end user applications to customers.
Hence, a mesh router is not required for these types of networks. The basic architecture is shown in Fig. In Client WMNs, a packet destined to a node in the network hops through multiple nodes to reach the destination. Client WMNs are usually formed using one type of radios on devices. Fig 3. Client WMNs 3. Mesh clients can access the network through mesh routers as well as directly meshing with other mesh clients.
While the infrastructure provides connectivity to other networks such as the Internet, Wi-Fi, WiMAX, cellular, and sensor networks; the routing capabilities of clients provide improved connectivity and coverage inside the WMN. The hybrid architecture will be the most applicable case in our opinion. Fig 4. Due to the recent research advances in WMNs, they have been used in numerous applications. The mesh topology of the WMNs provides many alternative paths for any pair of source and destination nodes, resulting in quick reconfiguration of the path when there is a path failure.
WMNs provide the most economical data transfer coupled with freedom of mobility. Mesh routers can be added incrementally to improve the coverage area. The obvious problem here is the location of the access point in the home, which may lead to dead zones without service coverage. These problems can be solved by replacing all the access points by the mesh routers and establishing mesh connectivity between them. This provides broadband connectivity between the home networking devices and only a single connection to the Internet is needed through the gateway router.
By changing the location and number of mesh routers, the dead zones can be eliminated. Fig 5 shows a typical home network using mesh routers. Fig 5.
All the traffic in community networking goes through the Internet, which leads to inefficient utilization of the network resources. The last mile of wireless connectivity might not provide coverage outside the home.
Community networking by WMNs solves all these problems and provides a cost effective way to share Internet access and other network resources among different homes. Fig 6 shows wireless mesh networking by placing the mesh routers on the rooftop of houses.
There are many advantages to enabling such mesh connectivity to form a community mesh network. For example, when enough neighbors cooperate and forward each others packets, they do not need individual Internet connectivity; instead they can get faster, cost-effective Internet access via gateways distributed in their neighborhood. Another advantage is that neighbors can cooperatively deploy backup technology and never have to worry about losing information due to a catastrophic disk failure.
Another advantage is that this technology alleviates the need for routing traffic belonging to community networking through the Internet. For example, distributed file storage, distributed file access, and video streaming applications in the community share network resources in the WMNs without using the Internet, which improves the performance of these applications.
Neighborhood community networks allow faster and easier dissemination of cached information that is relevant to the local community. Mesh routers can be easily mounted on rooftops or windows and the client devices get connected to them in a single hop.
Wireless mesh network-based Community Networking 4. During disasters like fire, flood, and earthquake, all the existing communication infrastructures might be collapsed. So during the rescue operation, mesh routers can be placed at the rescue team vehicle and different locations which form the high-bandwidth mesh backbone network, as shown in Fig 7. By providing different communication interfaces at the mesh routers, different mobile devices get access to the network.
This helps people to communicate with others when they are in critical situations. These networks can be established in less time, which makes the rescue operation more effective. Fig 7. In this section, we present different research challenges facing mesh networks.
In the context of WMNs, the issues which affect their performance have been characterized below: 5. The aforementioned requirements make the design of the MAC functions highly challenging. Several distributed multi-hop MAC protocols have been proposed which improve the throughput in multi-hop paths. However they are still far from being optimum solutions to be exploited by the network operator for real commercial breakthrough.
Apart from these, one needs to properly identify the issues related to the spectral efficiency of both high frequency and low frequency mesh systems. Proper characterization for the mesh capacity constraints and the understanding of the used network and its application is very important in determining the practical utility of mesh networks and the enabling technologies. It is also important to consider how mesh networks could live alongside existing radio systems, in terms of interference and coexistence strategies.
This functionality should be assured by the mesh routing protocol. Some efforts have been initiated to adapt the ad-hoc routing protocols for WMNs. But due to the fact that the ad-hoc routing protocols lack various important performance factors such as scalability, fault tolerance, QOS metrics, load balancing, lack of cross layer interaction etc.
In contrast, certain areas such as mobility and power management in ad-hoc networks and WMNs have totally different requirements, which made ad-hoc routing solutions not appropriate for WMNs. In order to resolve the above issues, innovative solutions are indispensable in WMNs.
Wireless Mesh Networks: Architectures and Protocols
Zigbee is a wireless technology developed as an open global standard to address the unique needs of low-cost, low-power wireless IoT networks. The The specification is a packet-based radio protocol intended for low-cost, battery-operated devices. The protocol allows devices to communicate in a variety of network topologies and can have battery life lasting several years. The Zigbee protocol has been created and ratified by member companies of the Zigbee Alliance. Over leading semiconductor manufacturers, technology firms, OEMs and service companies comprise the Zigbee Alliance membership.
The book discusses a very promising and effective approach in wireless communications called Wireless Mesh Networks WMN and its related issues. Meshes with external access capability, i. A full overview of WMNs with a technical assessment of mesh and multi-hop networking will be highlighted. Chapters in this book will provide a clear overview and s Chapters in this book will provide a clear overview and summary and will evaluate some practical examples of upright mesh applications.
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IEEE The IEEE As a standard, the document was iterated and revised many times prior to finalization. They are commonly used today to provide wireless connectivity in the home, office and some commercial establishments.
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Skip to search form Skip to main content You are currently offline. Some features of the site may not work correctly. DOI: Gungor and E. Natalizio and P. Pace and S.
The success of the layered architecture has been its ability to provide modularity and transparency. The established layered architecture is the result of the specific requirements and capabilities of wired networks that reach back to the 70ies. On the other hand, wireless ad-hoc and mesh networks enable many new and exciting applications, including entertainment networks, sensor networks, smart homes and buildings, and automated highways and factories. These emerging systems will have enormous variation in their device capabilities, network requirements, and application demands, giving rise to significant wireless network design challenges. However, optimizing within the conventional layers is generally insufficient to provide the optimal performance for next-generation wireless networks. Hence, it is imperative that network protocols and designs are engineered by jointly optimizing across the layers cross-layer design , which usually results in a clean-slate protocol architecture. In particular, the objective of cross-layer design is not the elimination of the layered architecture itself.
Fast and free shipping free returns cash on delivery available on eligible purchase. A security protocol for ad hoc wireless networks should satisfy the following requirements.
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