DMARC (Domain-based Message Authentication, Reporting & Conformance) is an enhancement to existing email authentication technologies. Details of the DMARC protocol and related information can be found at dmarc.org. Development of DMARC is still in progress and subject to change. This assistant has been updated based on draft-kucherawy-dmarc-base-04. Terms used in this assistant are taken from section 5.2 of that document.
Most of the the terms below have mouseovers that provide additional information about their meaning in DMARC.
 The optional size limit is not supported by all providers and use will cause interoperability problems as of 2014/08/03.
 May be very high volume - the ruf address must be prepared to receive a LOT of mail.