Gmail shows authentication data to the recipient

Yesterday Gmail rolled out some changes to their interface. One of the changes is that they are now showing end users authentication results in the user screen.
It’s really the next step in email authentication, showing the results to the end user.
So how does Google do this? Google is checking both SPF and DKIM. If mail is authenticated and the authentication matches the from address then they display the email as:
mail from steve to me
If we click on “details” for that message, we find more specific information.
full details of message showing signing domain and spf domainIn this case the mail went through our outgoing mailserver to gmail.
Mailed-by indicates that the message passed SPF and that the IP address is a valid source of mail from wordtothewise.com.
Signed-by shows the domain in the DKIM d=. In this case, we signed with the subdomain dt.wordtothewise.com. That’s what happens when you sign using the domain in the From address (or a subdomain of it).
For a lot of bulk senders, though, their mail is signed using their ESP’s domain instead.  In that case Gmail shows who signed the mail as well as the from address.

And when we click on “details” for that message we see:
3rd party signature detailsThis is an email from a sender using Madmimi as an ESP. Madmimi is handling both the SPF authentication and the DKIM authentication.
As an aside, this particular  sender has a high enough reputation that Gmail is offering me an unsubscribe option in their interface.
Gmail is distinguishing between first party and third party signatures in authentication. If the mail is authenticated, but the authentication appears to be handled by a separate entity, then Gmail is alerting recipients to that fact.
What does this mean for bulk senders?
For senders that are signing with a domain that matches their From: domain, there is no change. Recipients will not see any mention of your ESP in the headers.
However, if you are using an ESP that is signing your mail with a domain they own, then your recipients will see that information displayed in the email interface. If you don’t want this to be displayed by Gmail, then you will need to move to first party signing. Talk to your ESP about this. If they’re unsure of how to manage it, you can point them to DKIM Core for an Email Service Provider.
Gmail blogpost about the changes
Gmail help page about authentication results

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DKIM implementation survey: prelim results

First off, I want to thank everyone who participated in the DKIM implementation survey. This week has been pretty hectic so far, so I haven’t had a chance to actually dig down into the data from the survey, but I thought I’d post some preliminary results.
The ESP survey had 45 respondents. 30% of those sent more than 15 million emails a month.
Of all the respondents: 40% are signing with Domain Keys, 51.1% are signing with DKIM.
Of all respondents: 79.5% are signing with Domain Keys and 78.8% are signing with DKIM to access services (whitelists or FBLs) provided by the ISPs.
50% of those not signing with Domain Keys are not doing so because customers have not requested it.  61% of those not signing with DKIM are not doing it because of technical difficulties with deployment.
The ISP survey had 16 respondents, with 37.5% handling less than 500,000 mailboxes and 18.8% handling more than 15 million mailboxes. 75% of respondents said they are not checking Domain Keys on inbound mail. 56% said they are not currently checking DKIM on inbound mail.
Only 10 ISPs answered the question if they plan to check either Domain Keys or DKIM.

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ESPs, Non-portable Reputation and Vendor Lock-in

I’ve seen some mentions recently of ESPs suggesting that if you use your own domain in the From: of mail you send through an ESP then that ESP can’t “do email authentication” properly unless they require you to edit your domains DNS settings. That’s not really so, but there is a kernel of truth in there.
The real situation is, unsurprisingly, a bit more complicated.
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Predictions for 2008

I did not have a lot of predictions for what will happen with email at the beginning of the year so I did not do a traditional beginning of the year post. Over the last 3 – 4 weeks, though, I have noticed some things that I think show where the industry is going.
Authentication. In January two announcements happened that lead me to believe most legitimate mail will be DK/DKIM signed by the end of the year. AOTA announced that approximately 50% of all email was currently authenticated. They did not separate out SPF/SenderID authentication from DK/DKIM authentication, but this still suggests email authentication is being widely adopted. AOL announced they will be checking DKIM on their inbound mail. I expect more and more email will be DKIM signed in response to this announcement.
Filtering. The end of 2007 marked a steady uptick in mail being filtered or blocked by recipient domains. I expect this trend to continue throughout 2008. Recipient domains are rolling out new technology to measure complaints, evaluate reputation and monitor unwanted email in ways that tease out the bad actors from the good. This means more bad and borderline email will be blocked. Over the short term, I expect to see more good email blocked, too, but expect this will resolve itself by Q2/Q3.
Sender Improvements. As the ISPs get better at filtering, I expect that many borderline senders will discover they cannot continue to have sloppy subscription practices and still get their mail delivered. Improved authentication and better filtering let ISPs pin-point blocks. Instead of having to block by IP or by domain, they can block only some mail from a domain, or only some mail from an IP. There are a number of senders who are sending mail that users do not want mixed with mail that recipients do want. Right now, if there is more mail that recipients want in that mix, then ISPs let the mail through. This will not continue to happen through 2008. Senders will need to send mail users actively want in order to see good delivery.
Less is more. A lot of other email bloggers have talked about this, and I will echo their predictions. Less email is more. Send relevant mail that your customers want. Target, target, target. Good mailers will not send offers to their entire database, instead they will send mail to a select portion of their database.
Feedback loops. Use of feedback loops by recipient domains will continue to grow.
Mobile email. More recipients will be receiving email on mobile devices.
Suggestions for 2008

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