Analysis of WMN networking technology

Due to the limited bandwidth of wireless networks, complex time-varying channel characteristics and open communication environment, the signals of nodes interfere with each other, and to provide service quality service, we must adopt effective network management and networking technology to improve the link capacity and network transmission efficiency. WMN's networking technology includes several key aspects: Network configuration and deployment, power control, mobility management and access control, and routing protocol design.

Network Configuration and Deployment

In order to make wmn have good scalability, fault tolerance, self-adjusting ability, large coverage and network capacity, network configuration and deployment need to be studied. First, need for mobility is weak, composed backbone network of mesh router deployment location planning, on the one hand, to ensure that there is no signal coverage blind area, the need for mesh router needs as low as possible to reduce costs; On the other hand, in hot spots, multiple paths are provided to increase the number of user accesses. It can be combined with multiple (MIMO) and directional antenna technology to further improve the network transmission capability.

Mesh routers can provide a variety of heterogeneous network access services, therefore, how to allocate a number of mesh router wireless interface to ensure connectivity between each network, is wmn should be solved. In addition, in wmn, multi-channel methods can be used to increase the throughput of the network, but in the wireless multi-hop environment, the multi-channel communication way also faces the more urgent problem: there are some problems in the literature, such as the multi-channel WMN distributed service distribution, the channel coordinated use and the broadcast support. And the multi-channel protocol is designed and implemented.

Power control

In Wmn, although there is no energy limit for mesh routers, power control is needed to ensure the connectivity of WMN, control network interference and improve frequency reuse rate. The appropriate transmission power can reduce the interference between wireless channel signals and improve the efficiency of spectral multiplexing.

This column more highlights: http://www.bianceng.cn/Network/wxwl/

Unlike mesh routers, mesh clients are generally mobile nodes, the energy of the node is limited. Therefore, the design of network protocol needs to consider the effectiveness of power. For example, some mesh clients may be IP telephony or a sensor, so power efficiency is a factor to consider. For some WMN applications, the realization of power control will optimize the connectivity of the network and improve the network performance.

Mobility Management and access control

WMN Mobility Management consists of two meanings:

Position management and mobile switching management. Location management is primarily used to address location registration, while mobile switching management involves switching initialization and creating new connections. Seamless connection service. In cellular networks, mobility management is centralized management by base station, mobile switching center and location database, while in ad hoc networks, mobility management and routing protocols are closely combined, which can be regarded as a distributed scheme.

WMN has the characteristics of multi-hop and low mobility, its mobility management needs to combine the two networks ' mobility management techniques. Access control is to ensure that users use a variety of wireless transmission technology, can be effectively access to wmn, especially in the local hotspot area, when the number of nodes, heavy load, how to control the access of new nodes to ensure the quality of service access nodes.

Routing protocol Design

WMN adopts multi-hop relay to realize network access, which makes routing protocol design reference to the routing protocol Design method of ad hoc network. But there are differences between the two. On the one hand, the ad hoc network is composed of AP, mesh router, gateway and so on, the mobility of nodes is relatively weak; On the other hand, most of the data services in WMN are sent to network joints by user nodes, while the ad hoc network mainly provides the traffic mode between nodes and nodes, in addition, The requirements are relatively weak in terms of power limits. In addition, the study of WMN routing protocols can also be used to refer to the routing techniques adopted in the Internet, such as the use of different routing protocols within and outside the autonomous domain.