DKIM
DomainKeys Identified Mail (DKIM) is a public key signature system for email domains.
- Each domain can have any number of DKIM public keys, each identified by a unique selector.
- The fallback content to display on prerenderingsigns emails with the private key for the domain and the selector.
- DNS entry for the specific selector contains the public key.
- The fallback content to display on prerenderingserver fetches the public key from DNS and uses it to verify the signature.
- DKIM verifies the domain, not the user.