Configure DKIM for Business Email Hosting

This article will outline the benefits of DKIM and how to setup DKIM on a Domain Name Sanity Business Email Hosting service.

What is DKIM?

DomainKeys Identified Mail (DKIM) is a method for associating a domain name with an email message, thereby allowing a person, role, or organization to claim some responsibility for the message. The association is setup by means of a digital signature which can be validated by recipients. Responsibility is claimed by a signer—independently of the message's actual authors or recipients—by adding a DKIM-Signature: field to the message's header. The verifier recovers the signer's public key using the DNS, and then verifies that the signature matches the actual message's content.

What are the benefits of DKIM?

Use with spam filtering
DKIM is a method of labeling a message, and it does not itself filter or identify spam. However, widespread use of DKIM can prevent spammers from forging the source address of their messages, a technique they commonly employ today. If spammers are forced to show a correct source domain, other filtering techniques can work more effectively. In particular, the source domain can feed into a reputation system to better identify spam. Conversely, DKIM can make it easier to identify mail that is known not to be spam and need not be filtered. If a receiving system has a whitelist of known good sending domains, either locally maintained or from third party certifiers, it can skip the filtering on signed mail from those domains, and perhaps filter the remaining mail more aggressively.

Anti-phishing
DKIM can be useful as an anti-phishing technology. Mailers in heavily phished domains can sign their mail to show that it is genuine. Recipients can take the absence of a valid signature on mail from those domains to be an indication that the mail is probably forged.

How do I setup DKIM on a Hosted Email domain?

The settings for DKIM will show in the DNS Settings of your Business Email Hosting service.