What is Domain Authentication?
Domain authentication is the process of configuring DNS records (SPF, DKIM, DMARC) to prove to inbox providers that your email server is authorized to send on behalf of a domain.
Domain authentication is the collective process of setting up DNS records that verify your email server is authorized to send mail for a specific domain. It combines three protocols: SPF (which servers can send), DKIM (cryptographic signature verification), and DMARC (policy for handling failures).
For SaaS platforms that send email on behalf of customers, domain authentication is critical for each customer's domain. Each customer needs their own SPF include, DKIM key pair, and DMARC policy configured in their DNS. This proves to Gmail, Microsoft, and other inbox providers that the emails are legitimate.
The challenge for platforms is scale: onboarding dozens or hundreds of customer domains, each requiring correct DNS configuration. Incorrect authentication is the #1 cause of deliverability problems in multi-tenant email, and debugging DNS issues across many domains requires tooling purpose-built for the task.
Why Domain Authentication Matters
Without domain authentication, emails are flagged as suspicious or rejected entirely. Gmail, Microsoft, and Yahoo now require proper SPF and DKIM for all senders. For platforms sending on behalf of customers, this means every customer domain must be individually authenticated—a process that's tedious to manage manually at scale.
How Ark Handles Domain Authentication
Ark automates domain authentication for every tenant. When a customer adds their domain, Ark generates the required DNS records (SPF, DKIM, CNAME) and provides step-by-step setup instructions tailored to their DNS provider. Ark continuously monitors authentication status and alerts you if records become invalid.
Frequently Asked Questions
What is domain authentication for email?
Domain authentication is configuring DNS records (SPF, DKIM, DMARC) to prove to inbox providers that your email server is authorized to send on behalf of a domain. It's required for inbox delivery and prevents your emails from being flagged as spam or phishing.
Do I need to authenticate every customer's domain?
Yes. For white label email, each customer's sending domain needs its own SPF, DKIM, and ideally DMARC records. This ensures emails from each customer's domain are individually verified and trusted by inbox providers.
How long does domain authentication take?
DNS propagation typically takes 15 minutes to 48 hours, though most records propagate within an hour. With Ark, the DNS records are generated instantly, and verification happens automatically once records are published.
Related Terms
SPF
Sender Policy Framework (SPF) is an email authentication method that specifies which mail servers ar...
DKIM
DomainKeys Identified Mail (DKIM) is an email authentication method that uses cryptographic signatur...
DMARC
DMARC (Domain-based Message Authentication, Reporting, and Conformance) is an email authentication p...
DNS Records
DNS records for email are entries in your domain's DNS that configure mail delivery (MX), sender aut...
Sending Domain
A sending domain is the domain used in the From address of emails, configured with DNS records to au...
Email Deliverability
Email deliverability is the ability to successfully deliver emails to recipients' inboxes rather tha...
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