The setting in the TXT record of the DNS server can be done by the information systems officer who manages the DNS server. <Example> Publish the public key of the DKIM creator signature as a text record in a subdomain of the sender (Header-From) domain. DMARC Email Authentication Settings DMARC (Domain-based Message Authentication, Reporting, and Conformance) is a sending domain authentication technology that uses both SPF and DKIM . DMARC allows you to define how to handle NG messages based on the results of SPF and DKIM authentication as a DMARC policy, either "do nothing," "quarantine," or "reject," and by referring to the DMARC policy when handling received emails, you can eliminate spoofed emails.
(Supplementary Note) DMARC enhances the safety of uk telegram database emails by evaluating the authentication results of both SPF and DKIM and detecting spoofing by a third party. If the destination email server judges DMARC as NG, or if there is no DMARC setting even though it is a mass delivery, there is a high possibility that the email will be treated as spam, so if you use a service with email delivery function, we recommend that you support "DKIM creator signature" and "DMARC" .
How DMARC worksHow DMARC works If you configure DMARC email authentication settings, emails will be authenticated and delivered to the recipient in the following sequence, as shown in the diagram above. Send emails with DKIM signatures from the email delivery system Evaluate the SPF and DKIM authentication results, and determine the action to take if authentication fails using DMARC. At this time, check whether either SPF or DKIM matches the domain in the From header (Header-From: displayed as the sender in the email app) to ensure there is no risk of spoofing.