DKIM (DomainKeys Identified Mail)

Definition: DKIM (DomainKeys Identified Mail) is an email authentication method that uses a cryptographic signature attached to outgoing emails to verify that the message was sent by the authorized domain and was not altered during transmission. DKIM works by adding a unique digital signature to the email header, which is created using a private encryption key. When the email reaches the recipient’s server, it checks this signature against the public key published in the sender’s DNS records to confirm the email’s integrity and authenticity.

The primary purpose of DKIM is to prevent email spoofing and protect against phishing attacks by ensuring that emails genuinely originate from the claimed sender. By validating an email’s origin and confirming it wasn’t tampered with, DKIM strengthens email security and boosts the credibility of legitimate communications. DKIM also improves email deliverability, as many email providers use DKIM as part of their spam-filtering criteria; authenticated emails are more likely to reach the inbox rather than being flagged as spam.

Analogy: DKIM is like putting a special, secret sticker inside your letter that only your friend can recognize. When your friend gets the letter and sees the sticker, they know it’s really from you because only you have that special sticker.