Working in conjunction with SPF and DKIM, DMARC is an open email standard to enable domain-level protection of the email channel. DMARC stands for “Domain-based Message Authentication, Reporting, and Conformance.”
Companies use DMARC to preserve their brand equity, eliminate customer support costs related to email fraud, and to renew trust and engagement.
Using DMARC will prevent spammers from getting emails that appear to be sent from your domain into recipients’ mailboxes. These spoofed emails can caused serious damage to their recipients – who may be your customers.
Because DMARC checks with your records whenever an email appears to have come from your domain, you can learn how many spam emails are being sent out with your domain’s name.
With DMARC, you are able to authenticate all legitimate email messages that appear to be sent from your domain, including those owned by third party domains. You can also publish and explicit policy that instructs email providers what to do if a message is determined not to be legitimate – either sending the message to a junk folder or rejecting it entirely.
Companies that use DMARC include Bank of America, Facebook, Microsoft, Yahoo, Google, and PayPal.
Because DMARC policies are published in the public DNS, anyone can use DMARC.
There is no purchase necessary with DMARC, but managing it can be time-intensive and technically challenging.


DKIM is an email authentication standard that cryptographically associates a domain name with an email message. Sent emails include a cryptographic signature that the receiving inbox can verify using DNS-hosted public keys.
Email recipients who validate a DKIM signature can use that validation to limit spoofing, spam, and phishing.
Any individual in an email’s transit path may choose to validate the signature of a signed email.
When a DKIM signature is used, the domain owner is backing up the validity of the email with his or her domain’s reputation.
Yes, you will need to add code in the appropriate agent and modify your DNS administrative tools to permit the creation of DKIM key records.
When verification is successful, DKIM provides a domain-level identifier that survives the forwarding of a message while SPF does not.
Although you may not have heard of DKIM, it was produced by a group of email industry leaders in 2004.
DKIM uses a DNS-based public key publishing service, a domain name identifier, and public-key cryptography.
Setting up DKIM yourself can be time consuming and technically challenging. Sendio makes it easy for your organization to put this technology to use to protect your reputation.
Sendio has a very simple-to-use feature that allows you to sign outbound messages. Using Sendio along with DMARC provides you a critical component to you security efforts.