Gmail showing authentication info

Yesterday Gmail announced on their blog they would be pushing out some new UI to users to show the authentication and encryption status of email. They are trying to make email safer.
There are a number of blog posts on WttW for background and more information.

The short version is that TLS is encryption of the email between the sending server and the receiving server.  It means mail can’t be intercepted or changed while between one server and another.
Gmail is now showing users whether a mail was sent using TLS.
If a message is sent without using TLS, there is an open red lock shown.
Open red lock = unencrypted
If you hover over the open red lock, Gmail tells you the “message was not encrypted”
Hover showing "message not encrypted"
Using TLS removes the open red lock.
Mail sent over TLS
These messages went to spam because, well, do you know how hard it is to find a mail server that’s not authenticated? I ended up sending using SWAKS from one of our VMs so I could control a whole bunch of things, including whether or not mail used TLS. Interestingly enough, Gmail was happy to accept the mail over IPv6 but temp failed anything I sent over IPv4.
Gmail is, apparently, also notifying if mail being sent is going to a recipient on a server not using TLS. I don’t have an easy way to test that.

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July 2015: The Month in Email

Once again, we reviewed some of the ways brands are trying (or might try) to improve engagement with customers. LinkedIn, who frequently top lists of unwanted-but-legitimate email, announced that they’ll be sending less mail. Josh wrote about giving subscribers options for both the type and frequency of messages, and about setting expectations for new subscribers. In each case, it’s about respecting that customers really want to engage with brands in the email channel, but don’t want the permission they’ve granted to be abused. I also wrote a brief post following up on our June discussion on purchased lists, and as you’d predict, I continue to discourage companies from mailing to these recipients.

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Google Postmaster Tools

Earlier this month Google announced a new set of tools for senders at their Postmaster Tools site. To get into the site you need to login to Google, but they also have a handy support page that doesn’t require a login for folks who want to see what the page is about.
We did register, but don’t send enough mail to get any data back from Google. However, the nice folks at SendGrid were kind enough to share their experiences with me and show me what the site looked like with real data, when I spoke at their recent customer meeting.
Who can register?
Anyone can register for Google Postmaster tools. All you need is the domain authenticated by DKIM (the d= value) or by SPF (the Return Path value).
Who can see data?
Google is only sharing data with trusted domains and only if a minimum volume is sent from those domains. They don’t describe what a trusted domain is, but I expect the criteria include a domain with some history (no brand new domains) and a reasonable track record (some or all of the mail is good).
For ESPs who want to monitor all the mail they send, every mail needs to be signed with a common d= domain. Individual customers that want their own d= can do so. These customers can register for their own access to just their mail.
ESPs that want to do this need to sign with the common key first, and then with the customer’s more selective key.
How does it work?
Google collects data from DKIM and/or SPF authenticated mail, aggregates it and presents it to a Google user that has authenticated the domain.
How do I authenticate?

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Filter complexity

URLBlockingForBlogDuring the Q&A last week, I mentioned an example of a type of filter trying to demonstrate how complex the filters are. There was some confusion about what I was saying, so I thought I’d write a blog post explaining this.

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