Siemens SCALANCE M812, Operating Instructions Manual

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The path costs to the root bridge are added from the port to port path costs from the bridge
to the root bridge.
Port role and port status
The port role and port status are only negotiated when the SHDSL connection is actually
established.
Note that the ring topology becomes unstable if the SHDSL connection speed is below 384
kbps. If the SHDSL connection is overloaded, a hello frame may arrive too late causing a
constant topology change.
4-wire mode
In 4-wire mode, two 2-wire cables are aggregated to form a virtual connection.
X2
X1
X2
X1
Note
To allow the two 2-wire cables to be aggregated to form a connection, additional settings are
necessary in WBM. For further information, refer to the configuration manual "SCALANCE M-800
Web Based Management".
5.6 Ethernet port
Connect the local network with the local applications to the Ethernet port, for example a
programmable logic controller, a machine with an Ethernet interface for remote monitoring or
a PC.
To set up the device, connect a PC with a Web browser to one of the Ethernet ports.
For the connection, use a path cable with an RJ-45 plug. You will find the properties of the
Ethernet interface in the technical specifications.
Connecting up
5.6 Ethernet port
SCALANCE M826
Operating Instructions, 10/2022, C79000-G8976-C362-07
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