Protection
9.4 Using the user program to set additional access protection
Automation system
System Manual, 12/2017, A5E03461182-AE
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9.4
Using the user program to set additional access protection
Access protection by means of the user program
In addition to restricting access to the display, you can also restrict access to a password-
protected CPU in STEP 7 using the instruction ENDIS_PW. You can find a description of this
block in the online help under the keyword "ENDIS_PW: Limit and enable password
legitimation".
9.5
Know-how protection
Application
You can use know-how protection to protect one or more blocks of the OB, FB, FC type and
global data blocks in your program from unauthorized access. Enter a password to restrict
access to a block. The password offers high-level protection against unauthorized reading or
manipulation of the block.
Password provider
As an alternative to manual entry of password, you can connect a password provider to
STEP 7. When using a password provider, you select a password from a list of available
passwords. When a protected block is opened, STEP 7 connects to the password provider
and retrieves the corresponding password.
To connect a password provider you have to install and activate it. A settings file in which
you define the use of a password provider is also required.
A password provider offers you the following advantages:
●
The password provider defines and manages the passwords. When know-how protected
blocks are opened, you work with symbolic names for passwords. A password is marked,
for example, with the symbolic name "Machine_1" n the password provider. The actual
password behind "Machine1" remains hidden from you.
A password provider therefore offers you optimum block protection as the users do not
know the password themselves.
●
STEP 7 automatically opens know-how protected blocks without the direct entry of a
password. This saves you time.
You will find more information on connecting a password provider in the STEP 7 online help.
Содержание Simatic S7-1500/ET 200MP
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