What is DMARC (Domain-based Message Authentication, Reporting, and Conformance)?

What is DMARC (Domain-based Message Authentication, Reporting, and Conformance)?
What is DMARC (Domain-based Message Authentication, Reporting, and Conformance)?

In today's email-connected world, there are few to no barriers to entry, making it easy for anyone to access and communicate with anyone. This, in turn, has increased the chances and probabilities of cyber threats, phishing attacks, and email fraud.

Email authentication is a topic of growing interest for organisations looking for better mechanisms and protocols to safeguard their networks. DMARC, one such security solution, is one such protocol. Let us learn what DMARC is and how it works.

What is DMARC (Domain-based Message Authentication, Reporting, and Conformance)?

DMARC’s full form is Domain-based Message Authentication, Reporting, and Conformance.

As the name suggests, DMARC is an email authentication protocol that enhances security through authentication, reporting, and conformance! It provides authentication services by allowing email domain owners to specify authentication mechanisms. It offers reporting solutions to the owners to be aware of the incoming email traffic.

Essentially, DMARC plays a vital role in maintaining the integrity of email communication within and outside the organisation’s network. DMARC does this by reducing the risk of phishing attacks and fraudulent activities and increasing the trustworthiness of the sender’s domain.

How Does DMARC Work?

  1. There are two email authentication technologies, namely SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail). BMARC operates by combining these two email authentication protocols and building upon these mechanisms to authenticate the legitimacy of a message received in the mail.
  2. The first requirement for the DMARC authentication process to start is having a DMARC DNS record. The owner of the domain usually publishes this record in order for the server to refer to it when it is time.
  • When the server receives an email, it will check for the domain’s DMARC report. After this, the SPF and DKIM protocols perform their task of authenticating and verifying the message.
  • SPF does so with the help of the published list of authorised receivers, whereas DKIM does it by authenticating the message using the cryptographic public key.

3. The server verifies a few aspects of the mail. It checks the DKIM cryptographic     signature to verify the integrity of the email. If there has been no compromise or tampering with the message, the signature will be shown.

4. It verifies the IP address of the sender and checks if the sender is present in the list of authorised IP addresses published in the DNS.

5. Lastly, it will check if the headers pass the domain check to identify them.

6. When the SPF and DKIM results are out, DMARC is responsible for authentication. If a message received fails these tests, thE mechanism will verify it. By following the mechanism and design of the protocol, it will decide whether to hold the message, reject it, or do nothing about it.

7. The receiver email server will report the DMARC reports about the rejected domain and then continue to report all the movement from that particular domain.

Benefits of DMARC

Enhanced Security

Implementing DMARC is a substantial step towards comprehensive email communication security. When we leverage the power and functions of email authentication protocols like SPF and DKIM along with DMARC, it becomes an evidently robust solution.

These protocols ensure legitimacy and integrity in the messages received.

Along with the header verification with SPF, the tool verifies the sender’s domain and authenticity as well. This prevents fraudulent IP addresses from getting into your inboxes and compromising email security.

Fraud Mitigation

As mentioned above, the collaborative powers of SPF, DKIM, and DMARC offer an all-inclusive perspective towards email authentication that leaves little to no space for fraudulent emails to enter your email inbox. This reduces or negates the chances of phishing attacks by sending fraudulent links or messages.

Unauthorised email addresses can also target individual emails along with organisations and networks. This has resulted in an increase in email fraud.

It is possible to prevent such frauds with the protection of DMARC. Due to the quarantine of suspicious emails and outright rejection of failed authentication checks, the risk of fraud is mitigated and minimised.

Brand Protection

When your email server is protected using e-mail authentication protocols, it becomes easy to trust the network. Your clients, customers and departments can freely navigate and operate the network email while having safe communication. This has a positive impact on the brand's reputation.

Since DMARC offers valuable insights by reporting and confirming the authorisation and authentication, it becomes easy to take action against suspicious and fraudulent activities. When your network implements stringent e-mail authentication protocols, it becomes easy for the receivers to have faith in the entire procedure.

Increased Visibility

DMARC reports detailed insights into the email traffic that is associated with the email domains. These reports contain information on authenticated and unauthenticated IP addresses and emails.

These reports also inform about the sources of these emails along with any potential issues that might need special attention from the administrators.

These analyses enhance the visibility of domain activities and allow the owners to make informed and better decisions to fine-tune the authentication policies even more.


As the landscape of digital communication evolves, maintaining the integrity of e-mail communication becomes crucial. DMARC stands out as a beacon of comprehensive security and provides a multifaceted approach towards network security.

By combining SPF and DKIM authentication, DMARC meticulously performs and enforces detailed reporting that empowers organisations to strengthen their email ecosystems.

Enable DMARC and integrate it with your e-mail server to enjoy maximised security through authentication.

Find the best service provider in network security, like Instasafe, to authenticate the identities on your network. Integrating e-mail authentication with other security solutions like Zero-Trust Network Access and Multi-Factor Authentication will fortify your network even more.

People Also Ask (PAA)

1. Why is DMARC important?

Since it offers numerous benefits, including the prevention of phishing attacks, safe email communication, a wholesome networking experience, and combating spoofing attempts, DMARC becomes an essential part of overall network security.

2. Can DMARC have an impact on legitimate or authenticated emails?

There are very less chances of DMARC affecting legitimate email messages. Since the protocol is designed to minimise the effect on legitimate emails and cancel all fraudulent ones, it is difficult to harm any legitimate emails in the presence of DMARC.

3. What are the DMARC reports?

DMARC report is a report that informs the domain owners about the percentage of emails that are approved and rejected, individual failures, the number of emails from one fraudulent address, etc. This offers deep insights to the owners about the domain’s current conditions.

4. Is DMARC difficult to implement?

It might feel complex to implement DMARC at first, but it is more manageable than you might think. The technical steps like configuration, settings, and monitoring are complex. However, managing the protocol is not very difficult!