Email Authentication Basics for SaaS Teams | EasyDMARC

Email Authentication Basics for SaaS Teams

6 Min Read

Email is integral to all online businesses, and so is the practice of authenticating email domains. SaaS companies rely heavily on email for marketing, cold sales pitches, product launches, customer communications, newsletters, and more.

But if you’re part of a SaaS company, how do you know spoofers aren’t misusing your reputation and brand name? That’s why a robust SaaS email authentication system is crucial. 

According to Statista, more than 306.4 billion emails were sent in 2020, a number expected to grow to 376.4 billion by 2025. Meanwhile, Deloitte reports that 91% of all cybercrimes begin with spoofing an unexpected victim. 

Email authentication is no longer a luxury. It’s become vital to protect your business, brand reputation, and trust relationships with partners and clients. Ignoring email authentication will cost you more than just time and sales. Read on to learn more.

What is Email Authentication? 

Email authentication for SaaS companies is a technical solution that verifies whether an email comes from the claimed sender only. As such, it blocks or prevents malicious and fraudulent acts like phishing and spamming. 

The Sender Policy Framework (SPF), DomainKeys Identified Email (DKIM), and Domain-based Message Authentication, Reporting, and Conformance (DMARC) are the three common email authentication standards. 

We’ll focus on understanding their basics. But before moving ahead, here’s why SaaS companies should invest in these services:

Benefits of Email Authentication for SaaS Companies:

  • Enhances a positive brand image
  • Protects your customers from cybercriminals
  • Minimizes the possibility of data breaching
  • Bolsters your brand’s trustworthiness
  • Improves email deliverability

What is the Mechanism Behind Email Authentication?

The basic authentication of an email involves confirming the origin of the email domain ownership of Message Transfer Agents (MTAs). MTAs transfer emails between the computer of a sender and a recipient. Thus, they are very reliable for catching spam or fraudulent emails

In easier words, the domain name system (DNS) stores email authentication protocols of all the domains and subdomains. To validate an email’s authenticity, the sender’s and receiver’s servers communicate with each other. This confirms the origin of an email.

For example, you receive a surprise gift from a friend. What’s the first thing you’d do?

You’d call them to find out whether they have actually sent you a gift. If they confirm, you’d open up the parcel, right?

But what if they say, “No, I haven’t sent you any gift”? You’d send the suspicious parcel back as it may contain something dangerous.

The same concept applies when striving to. authenticate your email domain and improve your email security. Our Small Business Guide to Secure Email explains more.

Steps for Email Authentication

Although the following steps may vary a bit from protocol to protocol, the basic structure stays the same.

  • STEP 1: The domain owner sets certain rules for emails sent from that particular domain and subdomain.
  • STEP 2: These rules are then used for email authentication and recorded in the DNS.
  • STEP 3: The recipient’s server validates every email’s authenticity by cross-checking it with the rules recorded in the DNS.
  • STEP 4: If the email is authentic, it proceeds to the recipient’s inbox. If not, then depending upon the instructions stored in the DNS, it is either quarantined or rejected.
  • STEP 5: A quarantined email goes into the recipient’s spam or junk folder, while a rejected email travels back to the sender’s inbox as a failed email.

Three Common SaaS Email Authentication Protocols

As mentioned above, the three widely used SaaS email authentication protocols are SPF, DKIM, and DMARC. Although we’ve talked about them a lot on our blog, let’s quickly gloss over each.


The Sender Policy Framework (SPF), tells the DNS which hostnames and IP addresses the domain owner shares for sending emails. So, any emails from unrecognized hostnames of IP addresses are highlighted as inauthentic since they don’t match the DNS record. 

To understand this in a better way, you can reconsider the gift example. Suppose the sender’s details mentioned on the package don’t match that of your friend’s. In this situation, you’ll reject the package. Similarly, the email is also rejected from entering the desired recipient’s inbox folder when deploying the SPF protocol to authenticate the email domain


This encrypted signature goes to the recipient’s server along with the email. It’s evaluated for authenticity.

In total, two keys are involved in the process. First, the administrator records a public key on the DNS. Second, a private key is used by the email servers. The encrypted digital signature allows the recipient’s server to retrieve the key for basic email authentication.

The number of keys tripled on DKIM between 2020 and 2021. The 1024-bit keys increased two-fold and 2048-bit keys by 4.5 times. This simply supports the increasing trust of customers looking for enterprise email security. 


Domain-based Message Authentication, Reporting, and Conformance (DMARC) isn’t a direct SaaS email authentication protocol. Rather, it specifies whether the sending domain has deployed SPF, DKIM, or both for email authentication. It’s gaining immense popularity and appreciation as it builds a common framework using SPF and DKIM—which consequently strengthens the system against cybercriminals. 

A legitimate email sometimes fails the SPF or DKIM protocols meant for SaaS email authentication. Despite this, the mailbox providers allow it to enter if they appear to come from a credible and genuine source. In this situation, DMARC clarifies the action required. 

One major reason to invest in DMARC services includes a report that contains the following information: 

  • Servers sending emails with your domain name
  • Percentage of DMARC authenticated emails
  • Servers failing to pass DMARC authentication
  • Actions taken on emails failing authentication

The Bottom Line

Nobody in the world wants cybercriminals to attack their website. The best solution to protect your SaaS business is by simply investing in the means to authenticate your email domain

Use our free domain reputation checker to see whether your domain has been associated with any kind of cybercrime like phishing and spamming.

Content Team Lead | EasyDMARC
Hasmik talks about DMARC, email security, and cyberawareness. She finds joy in turning tough technical concepts into approachable and fun articles in plain language.


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