DMARC, which stands for “Domain-based Message Authentication, Reporting & Conformance,” is an email authentication, policy, and reporting protocol. It builds on the widely deployed SPF and DKIM protocols, adding linkage to the author (“From:”) domain name, published policies for recipient handling of authentication failures, and reporting from receivers to senders, to improve and monitor protection of the domain from fraudulent email (source: dmarc.org)
To summarize this, it uses existing authentication to define what and how ISPs should react to a message which fails a set rule. Here’s an example of a DMARC record: Yahoo.com
The following includes the Value (DMARC), what the Policy is (Reject), and where to send the forensic report (RUA). This example highlights that many of the major ISPs have already moved their domain to a ‘Reject’ status, which indicates that spoofing is not allowed.
A Common Issue that can occur is when DMARC is enforced (none>reject). When DMARC is enforced, and authentication isn’t set up, THEN messages would fail to be delivered. DMARC should only be enforced if the email admin as a full understanding of the impact this status change could mean for the organization. If a sender is on the Revinate Shared Range, and they have DMARC enforced (P=REJECT), then it is required for the sender to authenticate all messages sent through Revinate. Please open up a ticket with support requesting authentication to be generated and added to the organization’s DNS or Hosting provider.
Adding DMARC is helpful when it comes to managing and protecting a hotel’s reputation. If your hotel is interested in enabling DMARC, please use the following resources to help with enabling this policy.