Siemens SIMATIC ET 200S Manual page 589

Slave
A slave can only exchange data with a → master when requested by it to do so. By
slaves we mean, for example, all DP slaves such as ET 200X, ET 200M, ET 200S,
etc.
SNMP
SNMP (Simple Network Management Protocol) is the standardized program for
diagnosis and setting parameters on the Ethernet infrastructure
Devices from many different manufacturers support SNMP on the Ethernet in the
office and in automation engineering.
Applications based on SNMP can be run in parallel with applications on
PROFINET on the same network.
The scope of supported functions varies depending on the device type. For
example, a switch has more functions than a CP 1616.
SSI
The position information is transferred synchronously on the basis of the SSI
(synchronous serial interface) protocol. The SSI protocol is used with absolute
encoders.
Stationary wiring
All the wiring-carrying elements (terminal modules) are mounted on a rail. The
power and electronic modules are inserted in the terminal modules.
Switch
PROFIBUS is a linear network. The communication devices are connected by a
passive cable -- the bus.
In contrast, the Industrial Ethernet consists of point-to-point connections: every
communication device is directly connected to exactly one other communication
device.
If a communication device is connected to multiple communication devices, this
communication device is connected to the port of an active network components --
the switch. Now additional communication devices (including switches) can be
connected to the other ports of the switch. The connection between a
communication device and the switch remains a point-to-point connection.
A switch also regenerates and distributes received signals. The switch "learns" the
Ethernet address(es) of a connected PROFINET device and other switches and
only forwards the signals that are directed to the connected PROFINET device or
the connected switch.
A switch has a specific number of terminals (ports). Connect a maximum of one
PROFINET device or another switch to every port.
ET 200S Distributed I/O System
EWA-4NEB 780602402-12
Glossary
Glossary-9