A DKIM record is a type of DNS TXT record. It contains the public key used by recipient mail servers to authenticate a message’s DKIM signature. The record includes specific elements like the name, version, key type, and the public key itself. Email service providers, such as Postmark, typically provide this record.
Understanding DKIM (DomainKeys Identified Mail)
DKIM is an email security protocol designed to ensure that emails remain unchanged during their journey from sender to recipient. It employs public-key cryptography, where a sending server signs an email using a private key. Recipient servers then use a public key, available from the sender’s DNS records, to verify the message’s source and integrity. Successful verification of the DKIM signature indicates the email’s authenticity.
Why DKIM Matters – especially with Google and Yahoo updates coming in April 2024!
Enhances Sender Legitimacy: DKIM reduces the risk of email spoofing. By signing emails, senders appear more legitimate, decreasing the likelihood of their emails being marked as junk or spam. DKIM isn’t mandatory but is recommended for better email security and delivery, especially since major ISPs like Yahoo and Gmail use it for verifying incoming messages.
Builds Domain Reputation: Over time, DKIM helps in building a domain’s reputation. As ISPs monitor your email practices, consistent good practices (like low spam rates and high engagement) bolster your domain’s credibility, enhancing email deliverability.
Limitations of DKIM
While DKIM ensures message integrity, it doesn’t encrypt the email’s content. Although many Email Service Providers (ESPs) use TLS for encryption during transmission, DKIM itself doesn’t provide end-to-end encryption of the message content. Once delivered, the DKIM signature remains in the email headers but doesn’t encrypt the email body.