What is DKIM (DomainKeys Identified Mail)?

DKIM, or DomainKeys Identified Mail, is a method that employs public-key cryptography to sign emails. This signing process involves a sender's mail server generating a digital signature that is linked to a specific domain. When the email is sent, the recipient's mail server can then verify that signature against the public key published in the sender's DNS records.

This cryptographic signing is crucial for establishing the authenticity of the sender's domain and helps confirm that the email content has not been altered in transit. By annotating messages with a digital signature, DKIM provides a level of trustworthiness, allowing email receivers to determine whether the message genuinely comes from the claimed domain.

The other options do not accurately describe DKIM. While DKIM can contribute to anti-phishing measures by verifying the sender's credentials, it is not primarily a phishing detection technique. It also does not serve as a tool for archiving emails or enhancing email storage, focusing instead on the authentication aspect of email delivery.