http://www.rfc-editor.org/rfc/rfc8063.txt
RFC 8063: Key Relay Mapping for the Extensible Provisioning Protocol, H.W. Ribbers, M.W. Groeneweg, R. Gieben, A.L.J. Verschuren2017-02-01T23:00:00-00:00This key relay mapping will help facilitate changing the DNS operator of a domain while keeping the DNSSEC chain of trust intact.