SIEMENS
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Siemens IK PI · 2015
Industrial Wireless Communication
IWLAN – Controller and Controller Access Points IEEE 802.11n
Overview
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Function
Fundamental principles of the controller-based Industrial
Wireless LAN
The SCALANCE WLC711 IWLAN controller enables centralized
management of an Industrial Wireless LAN. It automatically
detects new access points, establishes a connection to them,
and manages and coordinates access points and clients.
Thanks to the Layer 3 architecture, access points located in
different Layer 2 subnets can also be managed. This function
allows wireless expansion of an existing Ethernet network with-
out having to make changes to the existing network topology.
With the IWLAN controller, the IWLAN wireless infrastructure can
be divided into logical, service-based networks (
V
irtual
N
etwork
S
ervices). Different services, security requirements and access
criteria can thus be reliably managed, and different user groups
such as administrators, commissioning engineers, or visitors
can use the same wireless network.
In the same way, different applications such as Voice-over-IP
(VoIP), video and Internet access can use the same infrastruc-
ture. The result is optimal capacity utilization of the IWLAN
network.
If applications with high reliability and availability requirements
are to communicate wirelessly, either two IWLAN controllers can
be operated redundantly or the access points can be set up
redundantly (overlapping of the radio links due to two wireless
cards in the device).
In applications where cable connections are not possible or are
only possible with difficulty, the controller-based access points
can be reliably integrated into the network even without a cable
connection. Thanks to the mesh algorithms, the access points
can resume communication in the event of a network error.
The controller-based access points of the SCALANCE W780C
series can only be used with the SCALANCE WLC711 IWLAN
controller and can only be configured using this IWLAN control-
ler.
The IWLAN controller connects, manages and coordinates all
access point and clients such that the WLAN environment
appears like several IP subnets with central management.
The individual connections are additionally managed here, and
the stations can therefore move securely and reliably throughout
the entire radio network.
Diagnostics and management functions
As well as centralized management and wireless network con-
figuration, the SCALANCE WLC711 IWLAN controller also offers
error recording, wireless network monitoring, and documenta-
tion of network statistics.
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More information
Supplementary WLAN solutions for office environments can be
found on the Internet at:
© Siemens AG 2014