Linear Structure - Siemens SCALANCE X-300 Series Operating Instructions Manual

Network topologies

3.2 Linear structure

Technical options (network topologies)
The IE Switches X-300 simplify the expansion of a network regardless of the network topology.
You can use an IE Switch X-300 in the following network topologies:
● Linear structure
● Star/tree structure
● Ring with redundancy manager
The maximum cable length is 70 km for single-mode gigabit transmission. A mixed topology
consisting of IE Switch X-300 devices and OSMs/ESMs is possible at the electrical ports.
Operation of IE Switches X-300 and OSM/ESM in a common topology via optical ports is
possible when IE Switches X-300 use optical ports that support a data rate of 100 Mbps. This
is the case, for example, with the SCALANCE MM991-2 media module.
Using an IE Switch X-300 as the redundancy manager in a ring with redundancy manager
provides greater availability. If there is an interruption on the connection between these
switches, the IE Switch X‑300 used as redundancy manager acts like a switch and creates a
line (bus) from the ring within a very short time. As a result, a functional, end-to-end structure
is restored. For information on this topic, refer to the Configuration Manual "SIMATIC NET -
Industrial Ethernet Switches SCALANCE X‑300 SCALANCE X-400."
3.2 Linear structure
Functional description
Linear structures can be created with the IE Switches X-300. The cascading depth and total
span of a network are limited only by the signal propagation times of the communication
connections.
Properties of the linear structure
Each IE Switch X-300 communicates over a TP or FO cable with a neighboring Ethernet switch.
Communication is possible over the optical or the electrical ports.
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Operating Instructions, 11/2019, A5E01113043-24
SCALANCE X-300