Your mail provider signs each outgoing message with a private key and gives you a TXT record holding the public key.
DKIM
An email signature, checked against a public key in DNS, that proves a message came from your domain unchanged.
An email signature, checked against a public key in DNS, that proves a message came from your domain unchanged.
Your mail provider signs each outgoing message with a private key and gives you a TXT record holding the public key.