Quick Summary
DKIM (DomainKeys Identified Mail) is a digital signing standard that verifies emails genuinely come from the stated domain.
DKIM (DomainKeys Identified Mail) is an email authentication standard. It adds a digital signature to emails, allowing recipients to verify the message genuinely came from the stated domain and was not altered in transit.
How DKIM Works
Sender side: When an email is sent, the sending server adds a digital signature using a private key.
DNS record: The domain owner adds a public key record to DNS.
Recipient side: The receiving server retrieves the public key from DNS and verifies the signature.
Benefits of DKIM
Spam protection: Fake sender addresses are detected.
Phishing prevention: Domain spoofing is prevented.
Email deliverability: Delivery rates improve.
With SPF and DMARC: Complete email authentication is achieved.
ONS Mail DKIM Support
ONS Mail automatically configures DKIM signing. A separate DKIM key is generated for each domain, and DNS records are easily managed.