DKIM Explained: Increasing Email Security
DomainKeys Identified Mail (DKIM) adds a digital signature to your emails. Find out how it works and how to implement it.
What is DKIM?
DomainKeys Identified Mail (DKIM) allows the receiver to check that an email claimed to have come from a specific domain was indeed authorized by the owner of that domain. It uses cryptographic authentication to ensure the message wasn't tampered with in transit.
How It Works
When you send an email, your server adds a cryptographic signature to the header. The recipient server uses your public key (published in your DNS records) to verify the signature. This process is invisible to the end-user but vital for server-to-server trust.
Case Study: A financial company seen a 40% reduction in spoofing attacks after implementing strict DKIM signing. Use our Bulk Verifier to clean up old contacts that might be flagging your new secure emails as suspicious.
Benefits of DKIM
- Verifies Sender Identity: Proves the email actually came from your domain.
- Ensures Message Integrity: Confirms the content hasn't been altered after being sent.
- ISP Trustworthiness: High-volume senders with DKIM are less likely to be rate-limited by ISPs like Outlook or Gmail.
How to Implement DKIM
Most modern email providers (Microsoft 365, Google Workspace, SendGrid) generate the DKIM key for you. You simply need to add the generated CNAME or TXT records to your DNS provider (Cloudflare, GoDaddy, etc.).
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