I am currently configuring FTPS communication in Automation Studio for a 4PPC70 PLC and would like to confirm whether my approach follows recommended security practices.
Configuration steps performed:
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Created a certificate under Access and Security → Certificate Store (own certificate with auto-generated private key).
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Enabled secure communication in PLC configuration:
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Online Parameters → Protocol: Secure (SSL/TLS)
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FTP Server: ON (FTPS)
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Web Server: ON (HTTPS)
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OPC UA: Enabled
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Downloaded the configuration to the PLC.
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Connected using WinSCP with:
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Protocol: FTP
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Encryption: Explicit TLS/SSL
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Encountered error: “SSL3 alert write fatal: Protocol version”
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Resolved the issue by setting minimum TLS version to TLS 1.0 in client settings.
After this change, I am able to access PLC files successfully.
However, I would like to understand:
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Is this configuration considered secure?
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What are the recommended best practices for FTPS configuration in Automation Studio?
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Is using TLS 1.0 acceptable in this case, or should it be avoided?
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Are there additional security measures I should implement?
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What would be the most secure approach for configuring FTPS or alternative file transfer methods in this context?
Any guidance on achieving a more secure setup would be appreciated.
Thank you 
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