As legitimate email marketing senders, we all get frustrated when we get unsolicited email clogging up our inboxes. It’s not only infuriating it’s time consuming as well.

On top of this, phishing and spoofing are even more infuriating to us since that’s just plain illegal. Phishers are those people that act as a legitimate company you may or may not do business with and “spoof” the from address to make it look like that legitimate business. How many of us have clicked on a link from our bank, eBay, or another legitimate company asking us to “update our information” which may include our credit cards?

How Does an ISP Authenticate a Legitimate Email Sender?

As a way to fight this bad behavior many ISPs (AOL, Gmail, Yahoo!) are adopting authentication protocols for how they screen incoming email to their users. There are four recommended protocols that are available to email senders right now SPF, SenderID, Domain Keys, DKIM.

SPF and Sender ID are very similar and use the some of the same data points to verify if a sender is authorized to send from the sender’s domain.  Because of this similarity they are often referred to at the same time, SPF/SenderID.  SPF was the first widely adopted protocol used for email authentication and is still most broadly used.  SenderID was developed by Hotmail to also help verify the origin of the email.  The limitations with SPF/SenderID, which include the protocols no longer working when a message is forwarded, is why SPF/SenderID are most effective when used in tandem with other protocols.

Domain Keys (DK) and DKIM are also very similar; DKIM is technically the next generation of DK and has improved upon that earlier technology.

A New Measure to Weed Out Unscrupulous Email Senders – DKIM

DKIM (Domain Keys Identified Mail) is the newest protocol to be introduced and it is being quickly adopted by ISPs such as AOL, Gmail, Yahoo!, Bell South, Cox, and Earthlink and you can bet these make up a bunch of consumer email inboxes.

On a very basic level, DKIM is technology that looks at the sender’s domain (after the @  sign) and verifies to see if the email did, in fact, come from that domain. If it doesn’t match then there is a possibility that the email won’t go through or get flagged as potential spam.

On a deeper level, a digital signature is attached to each email. When it reaches the receiving party they check the signature by looking at two things in the email header (which normally most recipients don’t see): a private key, which is the signature of the sender and a public key, which verifies the hidden private key.

What You Should Know

So if you are using an email service provider that uses DKIM, you’re ahead of the game in getting your emails delivered more effectively. Why? Because as DKIM gets increasingly adopted by ISPs or the receiving party, chances are your recipients are either in a company that uses DKIM to verify incoming email or they use an email provider like Gmail to do the same.

One more thing: It’s a good idea to ask your email service provider how and if they deal with DKIM and other protocols that are being used.

GOOD NEWS: VerticalResponse is ahead of the curve! Since we know how important it is for our customers’ emails to be delivered at the highest rate possible, we’ve adopted all protocols including SPF, SenderID, Domain Keys and DKIM.

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