With the rise of the social internet and the ubiquity of e-commerce, spammers and phishers have a tremendous financial incentive to compromise user accounts, enabling theft of passwords, bank accounts, credit cards, and more. Email is easy to spoof and criminals have found spoofing to be a proven way to exploit user trust of well-known brands. Simply inserting the logo of a well known brand into an email gives it instant legitimacy with many users.
Users can’t tell a real message from a fake one, and large mailbox providers have to make very difficult (and frequently incorrect) choices about which messages to deliver and which ones might harm users. Senders remain largely unaware of problems with their authentication practices because there’s no scalable way for them to indicate they want feedback and where it should be sent. Those attempting new SPF and DKIM deployment proceed very slowly and cautiously because the lack of feedback also means they have no good way to monitor progress and debug problems.
DMARC addresses these issues. DMARC (Domain-based Message Authentication Reporting and Conformance) is an email validation system designed to protect your company’s email domain from being used for email spoofing, phishing scams, and other cybercrimes. DMARC take the advantage of the existing email authentication techniques SPF (Sender Policy Framework) DKIM (Domain Keys Identified Mail). DMARC adds an important function, reporting. When a domain owner publishes a DMARC record into their DNS record, they will gain insight in who is sending email on behalf of their domain. This information can be used to get detailed information about the email channel. With this information, a domain owner can get control over the email sent on his behalf.