Most providers use 3 email standards to help prevent spoofing and phishing of your organization’s email. These standards also help ensure your outgoing messages aren’t marked as spam. We recommend Workspace administrators always set up these email standards for Gmail:
SPF: Specifies the servers and domains that are authorized to send email on behalf of your organization.
DKIM: Adds a digital signature to every outgoing message, which lets receiving servers verify the message actually came from your organization.
DMARC: Lets you tell receiving servers what to do with outgoing messages from your organization that don’t pass SPF or DKIM.
Set up DKIM to help protect your domain against spoofing, and help prevent your outgoing messages from being marked as spam. Spoofing is a type of email attack that forges the From address of an email message. A spoofed message appears to be from the impersonated organization or domain. DKIM detects when a message has been modified, and when unauthorized changes are made to the message From: address.
Without DKIM, messages sent from your organization or domain are more likely to be marked as spam by receiving mail servers.