DKIM Signature

Overview

DomainKeys Identified Mail (DKIM) is an email authentication method that uses public-key cryptography to verify a sender's identity and ensure the integrity of the message content. DKIM prevents malicious actors from forging your domain in email headers and improves the chances that your messages are delivered to recipients' inboxes.

With DKIM in place, receiving mail servers can verify that:

• The message was truly sent by your domain.

• The message contents were not altered after it was sent.

Configuration and Behavior

1. How DKIM Works

• A digital, encrypted signature is added to the header of each outgoing email.

• The corresponding public key is published in the DNS of the sender's domain.

• The receiving mail server uses this public key to verify the signature.

• This confirms the message:

  • Came from the claimed domain.

  • Was not tampered with in transit.

Email recipients do not see the DKIM signature in their inboxes.

2. DKIM in Mapp Engage

• DKIM is configured during the initial setup of your Mapp Engage system.

• The DKIM domain may differ from your main Mapp Engage system domain.

• Mapp supports both delegated system domains and main domains for sendout.

Examples

If you want to send emails from additional domains, those domains must have a valid DKIM key. Contact your customer representative to register them.

3. What DKIM Does Not Do

• DKIM does not ensure that the message is safe or free of malware.

• DKIM does not instruct the receiving server how to handle the message (e.g., mark as spam or not).

• DKIM is one component of a broader email authentication strategy, alongside SPF and DMARC.

4. Impact on Deliverability

• Emails sent from domains without a DKIM signature are more likely to be flagged as spam or rejected.

• Always use a domain that has DKIM configured to maintain high deliverability.

5. Customizing the Sendout Address

• You may change the local part of the sender address (everything before the @).

• The local part is not included in the DKIM signature.

• Only the domain part (after @) must have DKIM configured.

For example:
If @news.brand.com has DKIM configured, both info@news.brand.com and support@news.brand.com are valid for sendout.