DomainKeys is a standard for authenticating email developed by Yahoo!. It allows an organization to claim responsibility for transmitting an email message. The receiver can verify the message comes from who claims to send it by comparing its encryption signatures against an encrypted public database.

DKIM guarantees only that the sender's identity is genuine. The value of the content is not guaranteed. Therefore, the sender's reputation really becomes important. If you are known to send spam, your DKIM authentication is almost a guarantee of spam. If you are known as an honest, reputable sender (that is, you have few spam/abuse complaints), your email deliverability improves as your DKIM authentication confirms the email is from a trusted source.

Benchmark Email uses DomainKeys Identified Mail (DKIM) authentication for its outgoing email messages. You can find out more by reading our article on email authentication.