DMARC – All Facts that you should know

DMARC – All Facts that you should know

DMARC, alias Domain-based Message Authentication, Reporting, and Conformance, is a technical standard that aids in protecting email users from any phishing or spam mail. Every email sender and receiver will get this benefit. An organisation can showcase its policy that informs its email authentication standards by using DMARC. It also helps the receiving mail servers regarding the ways to enforce these policies.

What is DMARC?

DMARC mentions the methods for every domain owner to publish the necessary practices for email authentication. It also mentions the actions that should be necessarily taken on mail. Permit to share the report of the actions taken by mail.

Individuals have the misconception that DMARC has its email authentication protocol. It does not have that protocol, but it is built on the SPF and DKIM, the prime authentication protocol.

Functionality of DMARC

DMARC is developed on the basic standards of SPF and DKIM, which are necessary for email authentication. The process of functioning DMARC is noticed as below.

Every domain administrator mentions the policy that defines email authentication. It also mentions how receiving email servers will handle emails that disrupt the standards.

How DMARC works

The inbound mail servers use the DNS to check the DMARC standards while it receives emails. Then these inbound servers make the necessary evaluation for the three key factors, and these are:

  • Whether the DKIM signature is valid or not
  • Whether the emails coming from the IP address are permitted by the SPF records of the sending domain or not.
  • Whether the headers of the message express exact domain alignment or not.

A brief on DMARC record

A DMARC record is added to the DNS database of an organisation, and this record is made based on the uniquely designed version of the standards of DNS TXT. Every DMARC record is denoted as IN TXT v=DMARC1\; p=none\;\;\; pct=100

What is the Domain Alignment of DMARC?

Domain Alignment or DMARC is the concept that always helps to expand the validation of the Domain. The domain alignment of DMARC is always similar to the Domain with the necessary information relevant to the other standards.

  • The From Domain and the Return Path of the Domain of the messages should always match for SPF.
  • The From Domain and the DKIM d of messages should always match for DKIM.


DMARC p = standards or policies

These are three choices for DMARC specifications for all domain users. These policies are:

  • None: Here, the emails are considered similar to the emails without any DMARC validation.
  • Quarantine: As per this policy, mails are accepted, but these are placed in some other places in the inbox of the mail recipient.
  • Reject: As per this policy, the messages get rejected instantly.

Do you need DMARC?

Good question! If you are engaged in a business where you need to send commercial and transactional emails daily, you need to opt for email authentication. This will evaluate whether your emails are actually from your business. So, opting for DMARC is an important step that will enhance the deliverability of emails you send. For more information see MailSlurp documentation.

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DMARC – All Facts that you should know

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