Email Authentication 101: DMARC, SPF, and DKIM

Email authentication has always been one of the most important factors impacting deliverability. Due to Google’s recent changes however, it’s now been brought to the forefront.

The term DMARC for example is currently the most searched keyword in the email space.

Therefore, implementing email authentication protocols like DMARC, DKIM, and SPF helps verify the legitimacy of email senders and prevents unauthorized users from sending fraudulent messages.

DMARC vs SPF vs DKIM

There’s a trend right now when it comes to writing, where they make you read an entire article before finding the answer. This is especially painful for complicated subjects like this, so we made it easy for you.

It’s important to note that DMARC, SPF, and DKIM are all connected. They should ideally work together to protect you from harmful senders.

• DMARC - Tells mail servers what to do if they don’t authenticate with SPF or DKIM
• SPF - Verifies if the email comes from an authorized server
• DKIM - Verifies the email’s integrity and authenticity using digital signatures

What is DMARC?

DMARC stands for Domain-based Message Authentication, Reporting, and Conformance. It’s a technical standard which helps protect email senders and recipients from advanced threats, which can be the source of an email data breach.

In a nutshell, DMARC adds a layer of protection for email senders by potentially rejecting any unauthorized usage of their domain, and preventing the use of your domain by spammers sending abusive content.

Advantages of DMARC

• Increased Trust and Reputation: By implementing DMARC, companies and organizations can improve their email’s domain reputation
• Enhanced Email Security: DMARC helps to reduce emailing phishing and spoofing attacks by ensuring that emails are authenticated
• Improved Deliverability: DMARC ensures that emails are legitimate, the result of this makes emails more likely to reach a recipients inbox instead of being marked as spam
• Compliance: By implementing DMARC, organizations and companies can help comply with various relegation and industry standards

What is SPF?

SPF stands for Sender Policy Framework. It is an email validation protocol that enables domain owners to define a list of authorized email servers that can send on their behalf.

Adding an SPF to your DNS (Domain Name System) will tell recipient servers which domains and IP addresses can be trusted to deliver email for your domain. In instances where an IP is not listed in your domain’s SPF record, the authentication will produce a failure. When this occurs, the incoming messages are often either filtered into the recipient’s spam/junk folder or they are rejected completely.

Advantages of SPF

• Enhances Domain Reputation: SPF helps to protect your domain’s reputation by ensuring that authorized senders can use your domain for sending emails
• Reduces Phishing and Spam: SPF assists in filtering out messages that have been sent from unauthorized sources
• Improves email deliverability: Help’s to validate emails that are sent from authorized servers, as a result email’s are more likely to reach a recipients inbox instead of being marked as spam

What is DKIM?

DomainKeys Identified Mail (DKIM) is a crucial step to validate and ensure your identity as a sender. This process is done by creating two keys, one of them will be private and saved on your sending SMTP server, while the other will be public and saved in the Domain Name System (DNS). After the email is received, parts of the private and public keys are compared to ensure that the encryption remains unchanged through transit.

Once the signature is verified with the public key by the recipient server, the message passes DKIM and is considered authentic.

Emails that do not pass DKIM authentication are likely to be filtered as spam. It is important to examine all emails that fail DKIM to determine if the sources are valid or potentially abusive. If you recognize a source is valid, you can investigate that sending infrastructure and make sure that your DKIM is set up correctly. If a source is not recognized, further investigation should be taken to make sure this is not an attempt to send malicious emails from your domain.

Advantages of DKIM

• Supports Brand Protection: DKIM helps to protect companies and organizations brand by preventing unauthorized use of it’s domain email communications
• Email Verification: DKIM ensures that the contents of an email has not been altered during transit, ensuring the integrity of the message
• Secures Email Forwarding: DKIM encryption allows emails that are forwarded to be validated and prevent the content from being flagged as spam

How to monitor DMARC, SPF and DKIM

Through Emailable’s Deliverability Tools, you are able to check whether or not your tested emails are passing DMARC, SPF, and DKIM. You will also see if they are aligned with the From Domain of your campaign.

Our team recommends testing on a regular basis. Test every sending structure that is used to send email with your sending domains. Monitoring changes that result in an authentication failure will have an adverse effect on your email deliverability.

These changes are more prevalent than ever with AOL/Yahoo and Gmail enforcing these three protocols. It has become even more important to make sure that DMARC, SPF, and DKIM are present and passing within all your broadcasts.

DMARC, DKIM, and SPF are essential tools in safeguarding email communication by ensuring that messages are authenticated and sources verified, significantly reducing the risk of spam. However, even with these measures in place, it is crucial to stay informed and continue to look out for phishing emails.

Need more assistance?

If your business is struggling with deliverability, navigating the complexities of an advanced tool on your own may not be the best solution. Emailable has a team of deliverability experts with over 20+ years of experience.

They can walk you through specific problems like:

• Landing in the spam folder
• Domain-specific issues
• Blacklisting
• High bounce rates
• Low open and click rates

➡️ Schedule a call with an expert