SPF stands for Sender Policy Framework. It is an authentication protocol which, when used allows senders to specify which IP addresses are authorized to send emails on behalf of a particular domain. To ensure that your customers and your brand are protected from phishing and spoofing attacks, you need to authenticate your email with a SPF record.
During an SPF check, email providers quickly verify the SPF record by looking up the domain name included in the “envelope from” address in the DNS, before delivering an email. In case the IP address sending email on behalf of this domain isn’t mentioned in the SPF record, the message will fail the SPF authentication.
Therefore, the one sending emails, must publish SPF records in the DNS in order to list which IP addresses are authorized to send emails.