Siemens SIMATIC NET SCALANCE X-200RNA Operating Instructions Manual page 38

Device description
5.4 SCALANCE X204RNA interfaces
Autonegotiation
With the autonegotiation mechanism, repeaters and end devices can automatically determine
the transmission speed and the transmission mode of the partner interface. This makes it
possible to configure different devices automatically. Two components connected to a link
segment can exchange information about the data transfer and can adapt their settings to each
other. The mode with the highest possible speed is set.
Note
The SCALANCE X204RNA operates permanently in autonegotiation mode and can therefore be
connected to other devices that either also use the autonegotiation mode or the "100 Mbps
mode FD (full duplex)".
Note
The SCALANCE X204RNA is a plug-and-play device that does not require settings to be made for
commissioning.
MDI / MDI-X autocrossover function
The advantage of the MDI /MDI-X autocrossover function is that straight-through cables can be
used throughout and crossover Ethernet cables are unnecessary. This prevents malfunctions
resulting from mismatching send and receive wires. This makes installation much easier for the
user.
The SCALANCE X204RNA supports the MDI / MDI-X autocrossover function.
Note
Please note that the direct connection of two ports on the switch or accidental connection over
several switches causes an illegal loop. Such a loop can lead to network overload and network
failures.
Transmission speed
The transmission speed of the Fast Ethernet ports is 100 Mbps full duplex.
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Operating Instructions, 04/2022, C79000-G8976-C342-07
SCALANCE X-200RNA