Siemens SIMATIC ET 200AL System Manual page 935

Industrial Ethernet
Guideline for setting up an Ethernet network in an industrial environment. The essential
difference compared with standard Ethernet is the mechanical ruggedness and immunity to
noise of the individual components.
Instruction
The smallest self-contained unit of a user program characterized by its structure, function or
purpose as a separate part of the user program. An instruction represents an operation
procedure for the processor.
Interface module
Module in the distributed I/O system. The interface module connects the distributed I/O
system via a fieldbus to the CPU (IO controller/DP master) and prepares the data for the
I/O modules.
Intermediate CA certificate
This is a certificate authority certificate that is signed with the private key of a root certificate
authority.
An intermediate certificate authority signs end-entity certificates with its private key.
The signature of these end-entity certificates is verified with the public key of the
intermediate certificate authority.
The "Subject" and "Issuer" attributes of the intermediate CA certificate must not be identical.
This certificate authority has after all not signed its certificate itself.
The "CA" field must be set to "True".
IO controller, PROFINET IO controller
Central device in a PROFINET system, usually a classic programmable logic controller or
PC. The IO controller sets up connections to the IO devices, exchanges data with them, thus
controls and monitors the system.
IO device, PROFINET IO device
Device in the distributed I/O of a PROFINET system that is monitored and controlled by an
IO controller (for example distributed inputs/outputs, valve islands, frequency converters,
switches).
Communication
Function Manual, 12/2017, A5E03735815-AF
Glossary
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