Email, What is DMARC
What do I need to know about DMARC?
Domain-based Message Authentication, Reporting and Conformance - verifies an email actually came from the domain it claims to be sent from. It verifies two things:
- SPF (Sender Policy Framework) - verifies the server sending the email is authorized to send email for that domain.
- DKIM signature - verifies the content of the message was not manipulated during transit using encryption key verification.
If you are forwarding your email, you will lose email if a domain has a DMARC=reject policy. In addition to the Federal Agencies, many large corporations also implement a dmarc=reject policy.
Some examples include PayPal, Linked-In, Apple, Amazon, etc.
A full list can be found at: https://dmarc.org/who-is-using-dmarc/