As I’ve wrote in the article: “10 Tips for Auditing & Improving Mail Server Performance“, Dkim or Domainkeys is one feature that can be used to increase the acceptance rate (eligibility) of email on the destination mail server.
DomainKeys or DKIM signature basically allowing good senders to “sign” a message to prove that it really did come from them. This process is obtained by signing the outgoing mail with a specific code corresponding domain name and identity of the mail server so it is considered valid and convincing as an authorized sender.
Domain Keys Identified Mail (DKIM) is a technology designed to make it difficult or impossible for criminals to steal the identities of legitimate organizations. This authentication technology allows good senders to “sign” a message to prove that it really did come from them..
DKIM originally written as sender authentication protocol developed in order to address the problem of forged email messages. Yahoo! released the DomainKeys specification and Cisco released the Internet Identified Mail specification. Both methods are based on cryptographic message signing. The two efforts have been merged, and the combined specification is known as DomainKeys Identified Mail (DKIM).
