industrial wireless local area network (IWLAN)
Industrial Wireless Area Networks (IWLAN) are wireless networks for industrial applications. In contrast to the wireless LANs(WLAN) used in companies and home networks, industrial wireless LANs must support real-time transmission, operate without interference, and comply with specified delay times and latency periods. The requirements for reliability, robustness and security are of crucial importance in industrial WLANs. In this context, one also speaks of Trusted Wireless.
Industrial wireless networking is characterized by the process and production environment in which wireless technology is used. The requirements for robustness, reliability and transmission security are crucial here. The impairment of radio transmission by electromagnetic interference emanating from production equipment poses a challenge to radio transmission reliability. Extreme temperatures and humidity influences, strong mechanical stresses on the measuring equipment or measurement on moving vehicles or rotating machines are also not comparable to the requirements for enterprise WLANs.
Real-time behavior of IWLANs
To prevent errors in the production process, the control and process data in industrial WLANs must be delivered within a specified delay time. This real-time behavior is realized by the Industrial Point Coordination Function( iPCF) access method and by shortening the forwarding time between access points, i.e. rapid roaming. Furthermore, it must be ensured that there is no packet loss during data transmission and that the transmitted data cannot be manipulated under any circumstances, as otherwise the production equipment could be damaged. This means that the data must be transmitted in encrypted form.
There are various approaches to Industrial WLANs. One approach is based on WLANs according to IEEE 802.11, while another, such as WirelessHART and ZigBee, is based on IEEE 802.15.4. Depending on the concept, the infrastructure of IWLANs can also be used for standard communication and for IP services such as Voice over WLAN( VoWLAN).