Which email verification method enables a sender to sign emails using a digital signature?

The method that enables a sender to sign emails using a digital signature is DKIM, which stands for DomainKeys Identified Mail. DKIM allows the sender to attach a digital signature to the header of an email message, which is created using a private key. The recipient's mail server can then use the sender's public key, published in the DNS records, to verify that the email was indeed sent by the actual sender and that the content of the email has not been altered.

This digital signature helps to establish the authenticity and integrity of the email message. By verifying the signature, the recipient can ascertain that the email was genuinely sent from the purported sender's domain and that it has not been tampered with during transmission. This is crucial for preventing email spoofing and phishing attacks.

While SPF (Sender Policy Framework) and DMARC (Domain-based Message Authentication, Reporting & Conformance) are related to email authentication, they do not directly use a digital signature. SPF specifies which mail servers are permitted to send emails on behalf of a domain but does not involve a signature mechanism. DMARC builds on SPF and DKIM to provide reporting and policy enforcement but does not itself offer signing capabilities. SSL/TLS provides encryption for email in transit but does not verify