This report addresses technological and marketing issues of wireless mesh networks (WMN) and it shows that such networks are playing a very important role in the development of Intelligent Transport Systems (ITS). WMNs allow building self-organized and self-healing architectures where all nodes are equally involved in the transport of video, voice and data, making decisions based on information received from neighbors. The network responds on each failure, and because it has in-built redundancy, re-routes traffic from a place of failure. Such survivable communications is very important in supporting of ITS, which may deal with unexpected factors and is operated, usually, by non-technical operators (drivers).
The report analyzes WMN structures, and deals with:
- Radio technologies utilized by WMN
- Routing protocols.
In discussion of radio technologies for WMN, we emphasize the importance of three forward-looking wireless protocols: IEEE802.11n, ZigBee and Ultra Wideband (UWB). Though the majority of WMNs, at the present time use slower IEEE802.11b, g technologies, it is our perception that these three protocols will be building blocks of WMN in the near future. Except ZigBee, these technologies allow transmission with a rate of hundreds Mb/s and support greater coverage. ZigBee-structured WMNs are already a today reality in spite of a fact that their speed of transmission cannot exceed a couple of hundreds Kb/s.
All discussed technologies have features that are useful in the WMN environment:
- Extremely low power consumption
- Inherent security features
- Low sensitivity to mutipath problems.
The report analyzes technological benefits and limitations of each radio technology and standardization process as well as presents the marketing analysis and forecast.
The report also addresses the standardization process for WMN, and discusses a status of the IEEE802.11s standard. It shows that, so far, almost every manufacturer of WMN nodes uses proprietary routing protocols, and this situation slows WMN development. Some of the most popular routing protocols in use by WMNs are discussed in the report.
WMN architectures found already many applications in the commercial market, though initially they were the military prerogative. Among the most popular applications, we addressed:
- Municipalities
- ITS
- Public safety communications
- Industrial automation
- Consumers.
Note that WMNs are perfect choice for ITS. These networks can be easily deployed in a very short period of time (for example, in the emergency situations), and each node may be associated with a car or an element of the infrastructure, as per an ad-hoc network scenario. Some technologies, such as UWB, may be used for dual purposes being a building block not only for communications devices, but for extremely precise radar as well.
The report provides market characteristics of WMN, and shows that the industry already has created a strong basis for future WMN expansion. We envision that in several years 802.11n and UWB will prevail in WMN applications required high-speed transmission (for example, video), and they will successfully compete with wired technologies, such as Fast Ethernet. ZigBee and 802.11a, b, g will be left for applications that do not require high speed transmission, such as, for example, industrial automation, or home networks.
The report also analyzes a status of the ITS development; and it shows that WMN may become a very important part of ITS.
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