In the world of electronic communication, securing emails is essential. Domain-based Message Authentication, Reporting & Conformance (DMARC) is a standard protocol to help organizational domain protect against impersonation attacks such as phishing/spoofing etc. In this glossary article, we would take an extensive look at DMARC, what it does, why it does it, how to use it, best practices, FAQ and other related terms.
Definition
DMARC (Domain-based Message Authentication, Reporting & Conformance) is an email authentication protocol intended to support domain owners in preventing their domains from misuse like email spoofing. dmIsDmARC is an Open Source community driven initiative to create an Open Source and vendor neutral mutually agreed upon interoperable specification… DMARC leverages the widely deployed SPF and DKIM protocols, which can be adopted separately or in conjunction with it.
Purpose
DMARC’s sole objective is to address email espionage attacks like Robocall, spam, and spoofing, for instance. DMARC allows domain owners to describe how unauthenticated email from their domain should be handled, thereby preventing fraudulent or otherwise unauthenticated mail from being sent on behalf of their domain. This further protects the brand reputation for organization’s while providing a secure channel of communication via email for recipients.
How DMARC Works
DMARC works by aligning the results of SPF and DKIM checks with the “From” domain in an email message. When an email is sent, the receiving mail server performs the following steps:
| Step | Description |
| 1. SPF Check | The server checks if the email is sent from an IP address authorized by the domain’s SPF record. |
| 2. DKIM Check | The server verifies the DKIM signature to ensure the email content has not been altered. |
| 3. DMARC Policy Evaluation | The server evaluates the DMARC policy of the sending domain to determine how to handle emails that fail SPF or DKIM checks. |
| 4. Reporting | The server sends a report back to the domain owner, detailing the results of the DMARC evaluation. |
Based on the DMARC policy, the receiving server can take actions such as allowing the email, quarantining it, or rejecting it entirely.
Best Practices
Implementing DMARC effectively requires careful planning and execution. Here are some best practices to consider:
1. Start with Monitoring: Begin by setting your DMARC policy to “none” to monitor email traffic and gather data without affecting email delivery.
2. Gradually Enforce Policies: Once you have sufficient data, gradually move to more stringent policies like “quarantine” and eventually “reject” to enhance security.
3. Regularly Review Reports: Analyze DMARC reports to identify unauthorized email sources and adjust your policies accordingly.
4. Align SPF and DKIM: Ensure that your SPF and DKIM records are correctly configured and aligned with your DMARC policy.
5. Educate Stakeholders: Educate your organization’s stakeholders about the importance of DMARC and how it contributes to email security.
FAQs
DMARC is an email authentication protocol that helps domain owners protect their domains from unauthorized use, such as email spoofing and phishing.
DMARC enhances email security by allowing domain owners to specify how unauthenticated emails should be handled, thereby preventing malicious actors from sending fraudulent emails.
The key components of DMARC include SPF, DKIM, and the DMARC policy itself, which dictates how emails failing authentication checks should be treated.
To implement DMARC, you need to publish a DMARC record in your domain’s DNS, configure SPF and DKIM, and monitor email traffic to adjust your policies over time.
The benefits of using DMARC include improved email security, protection against phishing and spoofing, enhanced brand reputation, and increased trust from email recipients.