Options Of Media Redundancy; Media Redundancy In Ring Topologies - Siemens SCALANCE X308-2M Operating Instructions Manual

3.4

Options of media redundancy

There are various options available to increase the network availability of an Industrial
Ethernet network with optical or electrical linear bus topologies:
● Mesh networks
● Parallel connection of transmission paths
● Closing a linear bus topology to form a ring topology
3.4.1

Media redundancy in ring topologies

Structure of a ring topology
Nodes in a ring topology can be external switches and/or the integrated switches of
communications modules.
To set up a ring topology with media redundancy, you bring together the two free ends of a
linear bus topology in one device. Closing the linear bus topology to form a ring is achieved
with two ports (ring ports) of a device in the ring. This device is the redundancy manager. All
other devices in the ring are redundancy clients.
Figure 3-5
The two ring ports of a device are the ports that establish the connection to its two
neighboring devices in the ring topology. The ring ports are selected and set in the
configuration of the relevant device. On the S7 Ethernet CP modules, the ring ports are
indicated by an "R" after the port number.
Note
Create the configuration of the devices to be connected to form a ring before you close the
ring.
SCALANCE X-300
Operating Instructions, 02/2012, A5E01113043-12
Devices in a ring topology with media redundancy
Network topologies
3.4 Options of media redundancy
37