What Is E-Mail Authentication?

E-Mail Authentication takes into account several properties of an e-mail to verify if the origin of the e-mail is in fact as it is represented in the headers of the message.

These methods prevent forged mail from going being sent from or sent to your mail servers. The great benefit of enabling these methods is to prevent mail from looking like it is coming from your domain(s). When enabled, these methods should reduce the amount of bounce messages or unwanted e-mails received when spammers spoof one or more of your e-mail addresses.

What Is SPF? (Sender Policy Framework)

Sender Policy Framework (SPF) is an anti-spam method in which the Internet domain of an e-mail sender can be authenticated for that sender, thereby discouraging spam mailers, who routinely disguise the origin of their e-mail, a practice known as e-mail spoofing. SPF and other anti-spoofing initiatives, such as Domain Keys, work by making it easier for a mail server to determine when a message came from a domain other than the one claimed.

SPF will specify which machines are authorized to send e-mail from your domain(s). This means that only mail sent through this server will appear as valid mail from your domain(s) when the SPF records are checked.

SPF can be enabled, however this is only effective on a server that is set up as the authoritative DNS server for the zone.

What Are DomainKeys?

DomainKeys provides a way for E-mail Providers to verify the e-mail sender and the integrity of the messages sent. This allows an e-mail system to prove a message was not altered during transit (e.g. proves the message is not a forgery) and that the message did come from the specified domain.

DomainKeys can be enabled, however this is only effective on a server that is set up as the authoritative DNS server for the zone.