Sender Policy Framework

Sender Policy Framework (SPF) is a technology that can detect and reject forged email during the SMTP dialogue. Specifically, SPF is a method that allows a domain to explicitly authorize the hosts that may use its domain name. In addition, a receiving host may be configured to check this authorization. SPF can thus significantly reduce the instances of forged email. See: Chapter 15, Handling Forged Email Using the Sender Policy Framework, in Sun Java System Messaging Server 6.3 Administration Guide