Siemens SIMATIC S7-1500 System Manual page 385

In the office setting and in automation engineering, devices from a wide range of vendors on
the Ethernet support SNMP.
You can operate SNMP-based applications on the same network in parallel to applications
with PROFINET.
The scope of supported functions varies depending on the device type. For example, a switch
has more functions than a CP 1616.
Switch
PROFIBUS is a linear network. The communication nodes are linked by means of a passive
cable - the bus.
By contrast, Industrial Ethernet consists of point-to-point connections: Each communication
node is directly connected to exactly one communication node.
If you want to link a communication node to several communication nodes, you connect this
communication node to the port of an active network component (the switch). You can
connect other communication nodes (including switches) to the other ports of the switch.
The connection between a communication node and the switch remains a point-to-point
connection.
A switch thus has the task of regenerating and distributing received signals. The switch
"learns" the MAC addresses of a connected PROFINET device or additional switches. The
switch only forwards those signals that are intended for the connected PROFINET device or
switch.
A switch has a specific number of connections (ports). You connect at most one PROFINET
device or additional switch to each port.
Switched S1 device
The "Switched S1 device" function of the CPU enables operation of standard IO devices on the
S7-1500R/H redundant system.
PROFINET communication runs on an AR between the primary CPU and the standard IO
device. When replacing the primary CPU, the standard IO device is briefly disconnected from
the S7-1500R/H redundant system until the new primary CPU has set up an AR to the
standard IO device. If a line topology in S7-1500H is interrupted, the backup CPU establishes
an AR to the standard IO device after a short time.
Synchronization module
You use the synchronization modules to create the redundancy connections between the
CPUs of the redundant S7-1500H system. You need two synchronization modules per CPU
that you connect in pairs with fiber-optic cables.
System states
The system states of the S7-1500R/H redundant system result from the operating states of
the primary and backup CPU. The term system state is used as a simplified expression that
refers to the operating states that occur simultaneously on both CPUs. The S7-1500R/H
redundant system has the system states STOP, STARTUP, RUN-Solo, SYNCUP and RUN-
Redundant.
S7-1500R/H redundant system
System Manual, 11/2022, A5E41814787-AD
Glossary
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