Your domain's DMARC policy can be configured with different Policy Selectors, sometimes referred to as "Tags", Various tags are used to instruct remote email servers handle email from your domain name. You can start off by instructing remote email servers to ignore emails that fail DMARC authentication and proceed with their normal handling of email. Later, you can move a more strict policy which will instruct remote mail servers to quarantine emails that fail DMARC authentication and to move that email into the recipients junk mail or spam folder. Finally, you can instruct remote email recipient servers to completely reject a percentage or all emails that you have not implicitly authorized to send email on behalf of your domain's email addresses. The last The reject option being the most strict of all policies, caution should be used before moving to a reject policy.
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