Which technology is primarily used to validate the sender's email address?

The chosen answer, Sender Policy Framework (SPF), is primarily focused on validating the sender's email address by allowing domain owners to specify which mail servers are permitted to send emails on behalf of their domain. When an email is received, the recipient's mail server can check the SPF record published in the DNS settings of the sender's domain to verify whether the email came from an authorized source. This validation helps prevent spoofing, where malicious actors attempt to send emails pretending to be someone else.

SPF is critical for maintaining the integrity of email communication and enhancing security by ensuring that emails are originating from legitimate sources associated with the domain. This technology is widely used in various email security practices to reduce the risk of phishing attacks and unauthorized email sending.

Other options, while related to email security, serve different purposes. URL filtering is centered around restricting access to certain web domains, and email archiving solutions focus on storing and managing emails for compliance and retrieval rather than validating sender authenticity. DomainKeys Identified Mail (DKIM) serves to ensure that the content of the emails has not been altered in transit and provides additional authentication, but it does not primarily validate the sender’s email address in the same way SPF does.