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Siemens Desigo Desigo Room automation - Engineering, mounting and installation CM111043en_13
Smart Infrastrructure Ethernet network 2020-04-30
9 Ethernet network
9.1 IT security
· Building automation and control systems must use a separate technical network
with very restricted and selective connection to the rest of the intranet and no
connection at all to the internet. This can be done using a VLAN or a separate
subnet.
· If access from the rest of the intranet is required: Use a router with very selective
bridging.
· Prevent unauthorized access to any infrastructure (e.g. cables, LAN ports, IT
devices as routers, building automation devices) with appropriate measures, e.g.
lockable cabinets / panels.
See documents [10], [11], [12] for detailed information.
9.2 Network topologies
You can use the following bus topologies:
· Star topology (general).
· Line topology (for room automation).
· DXR2... and PXC3... can be mixed.
Switch
PXC3...
DXR2..
DXR2...
PXC3...
Switch Switch
Switch
11043z16_01
· The number of room automation stations is limited to 20 for a line topology
(daisy chain).
Topologies
Star topology
Line topology
Notes