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SPF




Sender policy framework is an email validation system, mail exchange can verify incoming email from a domain comes from a host authorized by domain administrators. Authorized sending host addresses for a domain is published in DNS (Domain Name System) record for that domain.

Smtp, simple mail transfer protocol permits any computer to send emails claiming to be from any source address. This is used by spammers to create forge emails.

During SPF check, receiving email server verifies sender IP address in the DNS record of the sender email. If the IP is found, SPF check is considered as PASS.
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