A standard that builds on SPF and DKIM: it confirms the domain shown in the From address lines up with what they checked. Domain owners use it to say how receiving servers should treat messages that fail, and where to send reports about them.
Also called Domain-based Message Authentication, Reporting and Conformance.
Read more: Microsoft Learn
In the Ultra Transcenders books
Each book explains DMARC in context, with comparison tables and the common traps.
Terms in this definition
- Standard deployment type
A Foundry deployment type billed per token that keeps processing of prompts and responses inside the Azure geography of the resource, meeting data residency needs at lower volumes.
- SPF
A DNS TXT record naming which sources may send email for a domain, so receiving servers can catch spoofing. DMARC and DKIM complement it.
- DKIM
A standard for authenticating email: the sending domain adds a digital signature over parts of each message, letting the recipient confirm nothing was changed along the way.
- Domain
A way of grouping workspaces by area of the business, in support of a data mesh approach. Items take on their workspace's domain, letting you filter the OneLake catalog by it, and certain tenant settings can be passed to domain admins; domains have no effect on access permissions.
- Agents (classic) API
First-generation Foundry Agent Service API, based on threads, messages and runs. It is deprecated, replaced by conversations and responses, and retires on 31 March 2027.
- WHERE
Limits a SELECT, UPDATE or DELETE to just the rows meeting a condition. Omit it, and the statement hits every row.
Related terms
- Honor DMARC record policy
When on, the DMARC policy that a sending domain publishes determines how a message is handled, in Defender for Office 365 and Exchange Online Protection anti-phishing. A different action can be chosen for p=quarantine than for p=reject.