# DomainKeys Identified Mail (DKIM) DKIM is a **process of authenticating the validity of an e-mail by affixing a digital signature to the e-mail in the DKIM e-mail header.** The header includes the signature and a domain that should be used to retrieve the public key used for signing. It is important to note that the domain listed in the DKIM e-mail header does not have to match the sender's domain (`From` header). [[Domain-Based Message Authentication, Reporting and Conformance (DMARC)|DMARC]] fixes this. ## Sources - [[All You Need to Know About SPF, DKIM and DMARC]]