Siemens CP 1542SP-1, Operating Instructions Manual, Page: 50 / 118

Configuration
4.1 Security recommendations
CP 154xSP-1
50
Operating Instructions, 12/2019, C79000-G8976-C426-05
Security functions of the product
Use the options for security settings in the configuration of the product. These includes
among others:
● Protection levels
Configure a protection level of the CPU.
You will find information on this in the information system of STEP 7.
● Disabling the bus adapter ports
In the configuration disable a port of the bus adapter being used that is not required.
● Security function of the communication
–
Enable the security functions of the CP and set up the firewall.
If you connect to public networks, you should use the firewall. Think about the services
you want to allow access to the station via public networks. By limiting the
"transmission speed" via IP packet filter rules in the firewall, you make use of the
possibility of restricting flooding and DoS attacks.
– Use the secure protocol variants NTP (secure) and SNMPv3.
– Use the security functions of the telecontrol protocols, e.g. the DNP3 security options.
– Use the secure Open User Communication (Secure OUC) via the appropriate program
blocks.
– Leave access to the Web server of the CPU deactivated.
● Protection of the passwords for access to program blocks
Protect the passwords stored in data blocks for the program blocks from being viewed.
You will find information on the procedure in the STEP 7 information system under the
keyword "Know-how protection".
● Logging function
Enable the function in the security configuration and check the logged events regularly for
unauthorized access.
Passwords
● Define rules for the use of devices and assignment of passwords.
● Regularly update the passwords to increase security.
● Only use passwords with a high password strength. Avoid weak passwords for example
"password1", "123456789" or similar.
● Make sure that all passwords are protected and inaccessible to unauthorized personnel.
See also the preceding section for information on this.
● Do not use one password for different users and systems.