Self-signed certificate
To obtain a self-signed certificate, open a command prompt and execute the following command:
C:\key>c:\openssl\bin\openssl x509 -req -sha256 -days 10000 -in server.csr -signkey server.key -copy_extensions copyall -out server.crt
This command creates a server.crt file in the c:\key folder, which is valid for 10,000 days. This is the signed private key, which is also referred to as a self-signed certificate.
Signed and trusted certificate
To obtain a signed and trusted certificate, you must obtain a certificate signing request (CSR), send that file to a Certificate Authority (CA), and request that the CA issue a signed and trusted certificate. Each certificate authority has its own procedures and requirements. Use of this certificate results in higher reliability in exchange for greater cost and requirements. The signed and trusted certificate is the signed public key.