How to be sure that a message we receive is sent by a reliable sender? How to know if it is a legitimate email and not an attempt at spam or phishing? It is here that the DMARC protocol intervenes by ensuring the safety and authenticity of an e-mails of an organization, thus reinforcing the brand identity and the trust / customer confidence.

What does DMARC mean and what is it for?

DMARC is the acronym for “domain-based message authentication, reporting and conformance“. It is an authentication, policy and reporting protocol for e-mail, which is intended to combat phishing and fraudulent emails by authenticating email shippers.

At the very beginning, DMARC has established a standard in which senders and recipients agreed on how to interpret emails from areas supporting SPF protocols (“Sender Policy Framework“) and DKIM (“Domainkeys identified mail“). It was about to give the possibility to brand publish policies on how to handle an authenticated email, and allow recipients to provide authentication reports these brands so that they can improve and monitor their authentication system.

Their common goal was to develop a standard supported by a broad group of organizations. This resulted in the publication of the DMARC specification in January 2012.

Why is the DMARC is also important?

The omnipresence of the digital and in particular electronic commerce gives spammers and phishing high identity opportunities as well as theft of personal data, by imitating for example the logo or the name of a known organization. Thus, it becomes difficult for users to differentiate the true from the false, and it can be complicated for Internet access providers to know which messages distribute or not.

The DMARC therefore plays a key role since this protocol will help to authenticate and secure emails, thus participating in a better protection of users and organizations against different abuses. Abuse that, remember it, can sometimes cost very expensive and have heavy consequences for a business.

If you are a company and send commercial or transactional emails, it is imperative to set up several forms of authentication of your emails to validate that they come from your organization.

The DMARC protocol therefore presents several advantages such as increased email security in the various attacks, accurate visibility on how the domain of your organization is used on the Internet, a better deliverability of e-mails, a better image of Brand and strengthening the company / customer relationship.

How does the DMARC protocol work?

How DMARC works ?
To simply do DMARC protocols uses SPF and / or DKIM for authenticating senders of emails. It also relies on the domain name system (DNS). If a fraud is detected, Dmarc will ask the recipient server, depending on the domain owner’s policy, to quarantine or reject the message concerned.

Then, DMARC retransmits this information to the estate owner, in the form of a report, ensuring that the latter be aware of the suspicious activity detected and can inform his courier administrator. By performing this survey and alert work, DMARC limits or removes the user’s exposure to potentially fraudulent messages.

Good to know

The DMARC protocol proposes three choices to domain owners to specify the processing they wish to rely on the letters defined as suspects following the validation checks:

  • None (“p = none”); The email is then treated as it would be without the DMARC validation.
  • Quarantine (“P = Quarantine”); The email is accepted, but placed in another folder than the inbox, as in spam for example.
  • Rejection (“P = reject”); The email is simply rejected.

Who can use Dmarc?

DMARC policies are published in the public domain name system (DNS) and are accessible to all. As the specification is available without a license or similar restriction, any interested party is free to apply it.