Don't have an account? Sign up
If you're already signed up, please sign in
DKIM Key Rotation — the controlled replacement of a DKIM signing key and selector, with overlapping DNS publication when needed to preserve verification of messages in transit.
DKIM adds a digital signature to email. The sender protects the private key and publishes the public key in DNS under a selector. Validation shows that signed headers and body content were not changed after signing; it does not establish that the message is truthful.
DKIM Key Rotation — the controlled replacement of a DKIM signing key and selector, with overlapping DNS publication when needed to preserve verification of messages in transit.
The receiver reads the d= domain and s= selector from DKIM-Signature, retrieves the public key from DNS, and verifies the body hash and signature over the selected headers.
Protect the private key, use an adequate key size, rotate keys without interrupting delivery, and retain an old DNS key while messages signed with its selector may still be verified.