The SPF Sender Policy Framework: A system utilising DNS servers to validate that a given IP address is authorised to send mail for a specific domain system is a DNS Domain Name Server: A server that answers queries regarding the names and addresses on the internet. based system that allows mail server to check that the IP address of a source of mail is authorised to send mail for a given domain. When a mail message is received, FTGate retrieves the SPF records for the senders email address and verifies that it incudes the IP address of the sending server.
SPF checking is enabled in the Security Policy of an SMTP Simple Mail Transfer Protocol (A message send protocol) service. The result of the SPF check can also be used in the Filter Policy Rules.
SPF checks will not be performed for authenticated users (See Relay Control and Authentication)
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