Email Domains: SPF
SPF Sender Policy Framework
SPF is an email authentication method designed to detect forged sender addresses in emails (email spoofing), a technique often used in phishing and email spam.
SPF allows the receiver to check that an email claiming to come from a specific domain comes from an IP address authorised by that domain's administrators. The list of authorised sending hosts and IP addresses for a domain is published in the DNS records for that domain.