A commercial Certificate Authority is an organization that is in the business of creating high-quality certificates and using these certificates to sign your certificate requests.
Globally-signed certificates have the following advantages:
For inter-company communication, common trust in an outside, recognized authority may increase confidence in the security of the system. A Certificate Authority must guarantee the accuracy of the identification information in any certificate that it signs.
Certificate Authorities provide controlled environments and advanced methods to generate certificates.
The private key for the root certificate must remain private. Your organization may not have a suitable place to store this crucial information, whereas a Certificate Authority can afford to design and maintain dedicated facilities.
To set up globally signed identity files, you:
Create a certificate request using the createcert utility with the -r option.
Use a Certificate Authority to sign each request. You can combine the signed request with the corresponding private key to create the server identity file.