Certificates (keys) are stored in wide range of formats.
ASN.1 defines the structure of the key/certificate which can later be saved as binary (DER) or 'textual' (PEM)
Base64 translation of the x509 ASN.1 keys placed between well-known delimeters (e.g. -----BEGIN PRIVATE KEY-----)
x509 ASN.1 keys
Asymmetric, public key cryptography using trusted institution certifying ownership of public key.
Setting key-pair (with self-signed CA) for server consists of following steps:
- create private key for CA
- create self-signed CA cert
- create private key for server
- create csr (certificate signing request) for server
- sign csr using CA
Multiple parameters asked during certificate creation can be specified using config files: https://www.openssl.org/docs/manmaster/apps/config.html