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• Private CA-signed Certificates are issued by users who operate their own Private Certificate Authority (CA).
• Public CA-signed Certificates are issued by a trusted Certificate Authority (CA) that validates the domain owner. They are not created by users but are purchased from the trusted CA and therefore are not considered by the article.

There is no difference in using a Private CA or Public CA concerning the type functionality of X.509 certificates, the usage for Server Authentication / Client Authentication, or the security of connections. The only difference is that users have to trust the Private CA that they set up on their own.

Examples in the article make use of JS7 Release 2.7.2, OpenSSL 1.1.1k  FIPS 25 Mar 2021 and JS7 Release 2.7.2for Unix and OpenSSL 3.1.4 24 Oct 2023 for Windows. OpenSSL ships with Linux & other Unix OS and is available for Windows. Examples are available for Unix and Windows.

Setting up the Private CA

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