Anti-virus protection 
Install the latest commercial-quality antivirus software on the computer connected to the control 
system and maintain to keep the software up-to-date. 
 
Security measures to prevent unauthorized access 
Take the following measures to prevent unauthorized access to our products. 
•  Install physical controls so that only authorized personnel can access control systems and equip- 
ment. 
•  Reduce connections to control systems and equipment via networks to prevent access from 
untrusted devices. 
•  Install firewalls to shut down unused communications ports and limit communications hosts and 
isolate control systems and equipment from the IT network. 
•  Use a virtual private network (VPN) for remote access to control systems and equipment. 
•  Adopt multifactor authentication to devices with remote access to control systems and equip- 
ment. 
•  Set strong passwords and change them frequently. 
•  Scan virus to ensure safety of USB drives or other external storages before connecting them to 
control systems and equipment. 
 
Data input and output protection 
Validate backups and ranges to cope with unintentional modification of input/output data to control 
systems and equipment. 
•  Checking the scope of data 
•  Checking validity of backups and preparing data for restore in case of falsification and abnormali- 
ties 
•  Safety design, such as emergency shutdown and fail-soft operation in case of data tampering 
and abnormalities 
Data recovery 
Backup data and keep the data up-to-date periodically to prepare for data loss. 
 
When using an intranet environment through a global address, connecting to an unauthorized ter- 
minal such as a SCADA, HMI or to an unauthorized server may result in network security issues 
such as spoofing and tampering. You must take sufficient measures such as restricting access to 
the terminal, using a terminal equipped with a secure function, and locking the installation area by 
yourself. 
 
When constructing an intranet, communication failure may occur due to cable disconnection or the 
influence of unauthorized network equipment. Take adequate measures, such as restricting physi- 
cal access to network devices, by means such as locking the installation area. 
 
When using a device equipped with the SD Memory Card function, there is a security risk that a 
third party may acquire, alter, or replace the files and data in the removable media by removing the 
removable media or unmounting the removable media. 
Please take sufficient measures, such as restricting physical access to the Controller or taking 
appropriate management measures for removable media, by means of locking the installation area, 
entrance management, etc., by yourself.