Ad Hoc Networks; Other Wireless Technologies - Siemens SIMATIC NET System Manual

Basics of communication with Industrial Ethernet
1.5 Wireless LAN
1.5.10.2

Ad hoc networks

Ad hoc networks
In ad hoc mode, nodes communicate with each other directly (connection 4) without
involving an access point. The nodes access common resources (files or even devices, for
example printers) of the server (connections 1 to 3 in the figure). This is, of course, only
possible when the nodes are within the wireless range of the server or within each other's
range. Ad hoc networks can only be operated with the standard 802.11 "b".
As an alternative, wireless networks can be configured in "infrastructure mode".
1.5.11

Other wireless technologies

Wireless HART
HART (Highway Addressable Remote Transducer) is the wireless connection of field devices
in process automation for advanced diagnostics.
Just like WLAN, WirelessHART also uses the ISM frequency band (2.4 GHz and with a
maximum of 250 kbps) and automatically establishes meshed networks. The span of the
network is greater than the nominal wireless range of an individual node. The network
organizes itself by having all the connection information evaluated by a network manager.
With this information, redundant paths are made available automatically that can bridge the
failure of individual nodes. The main focus during the development of WirelessHART was
simple commissioning and maintenance of the self-organizing networks so that configuration
involved only minimum effort. The main area of application of WirelessHART is in the regular
transmission of small, non time critical-amounts of data at long intervals over relatively long
distances. Thanks to the low energy consumption, battery working lives of several years are
achieved.
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System Manual, 09/2019, C79000-G8976-C242-10
Industrial Ethernet