Thoughts on filters

One of the questions we received during the EEC16 closing keynote panel was why isn’t there a single blocklist that everyone uses and why don’t ISPs share data more. It would be so much easier for senders if every ISP handled mail the same as every other. But the world isn’t that simple, and it’s not always clear which mail stream is spam and which is good mail.

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There were quite a few answers but they basically boiled down to a few facts.

  • Different blocklists have different data strengths and weaknesses.
  • No blocklist has all a full view of all the bad mail.
  • You may want to have different polices for delisting depending on what kind of mail the blocklist is targeting. For instance, Spamhaus has different polices for different lists: CBL has self serve delisting, SBL requires email, ROSKO requires no traceable spam for 6 months.

The short reason was we use different lists and techniques because it makes the spam filtering better.

When I got home from the conference, I saw In-depth analysis of the lessons we learned while protecting Gmail users post. Among other things, it answered the “why not one blocklist” question. Even more, I think it did a really good job of talking about what email looks like from the receiving end.

Any defense can be defeated – Use defense in depth with multiple layers of protection.
Since no combination of detection systems at a given layer is perfect, there is a need to add multiple layers of defense to make it even harder for attackers.

One thing I’ve been trying to get across to marketers is that email is an a very malicious channel. Many of the bad mails out there, the ones the filters are aiming for, are dangerous and malicious. Those attackers spend a lot of time trying to figure out how to get past the defenses.

Make it hard for attackers to understand your defenses – Use overwhelming force and deploy many countermeasures at once.

It is very important to make probing more difficult for attackers by rolling out multiple changes. That way they are overwhelmed by the number of things to test and can’t easily figure out what changed.

This is why it’s so hard to test “what Gmail changed.” They are going out of their way to release multiple things at once. It’s also why it’s not really useful to test. It’s more useful to look at your mailing practices and see where they might be borderline and driving your reputation down.

The whole article is well worth a read. It gives a good overview of what Gmail is doing and how they think about email, filtering and dangers. It also gives examples of the different challenges they deal with on a regular basis.

Overall, it’s important to realize that filters are an important part of the email ecosystem. They are a big part of why it’s a viable marketing channel. Think of it this way, an unweeded garden is not as productive as a weeded garden. Weeds take nutrients away from the plants and stunt their growth. They also make it harder to find the actual produce at harvest time. Filters are the herbicides and weeding that keep gardens healthy and productive. Without them, no one could effectively use or trust email.

Dueling data
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Thoughts from #EEC16

EEC16 was my first Email Experience conference. I was very impressed. Dennis, Len, and Ryan put together a great program. I made it to two of the keynotes and both took me out of an email focused place to look at the bigger picture.
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Patrick Scissons discussed his experiences creating marketing and advertising campaigns for good and to share messages. Some of the campaigns were ones I’d seen as a consumer, or on the news. One of the campaigns he talked about specifically was for the group Moms Demand Action, looking at sensible gun control in the US. The images and symbology used in those campaigns were striking and very effective.
Kelly McEvers talked about her experiences as a correspondent in the middle east during the Arab Spring. She is an engaging speaker, as one who does radio should be. Her overall message and theme was that sometimes events are such that you need to throw the list away and go with it. As someone who lives by “the list” and tries to make sure I’m prepared for every eventuality I found that a very useful message. Particularly when throwing away “the list” turned into some massively successful stories.
In terms of sessions, I found the email content session fascinating. I blogged about content in email last week and did some live tweeting, too. What really hit me after that session was that good marketing drives deliverability. Everything that Carey Kegel was talking about in terms of better marketing, sounded like things I recommend to clients to drive deliverability.
Back in 2012 I was writing posts about how delivery and marketing were somewhat at odds with each other. The premise was that marketing was about creating mindshare, and repeating a message so often a recipient couldn’t forget it. In email, repetition can cause recipient fatigue and drive delivery problems. But what I’m hearing now, from the leading minds of email marketers, is that email marketing works better if you send relevant and useful information to consumers. Recipients are key and you can’t just keep hammering them, you have to provide them with some value.
It seems marketing has finally come around to the delivery point of view.
 
 

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March 2016: The Month In Email

Happy April! I’m just back from the EEC conference in New Orleans, which was terrific. I wrote a quick post about a great session on content marketing, and I’ll have more to add about the rest of the conference over the next week or so. Stay tuned!
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Here’s a look at what caught our attention in March:
On the DMARC front, we noted that both Yahoo and mail.ru are moving forward with p=reject, and Steve offered some advice for ESPs and software developers on methods for handling this gracefully. I also answered an Ask Laura question about making the decision to publish DMARC. Look for more on that in this month’s Ask Laura questions…
Our other Ask Laura question this month was about changing ESPs, which senders do for many reasons. It’s useful to know that there will generally be some shifts in deliverability with any move. Different ESPs measure engagement in different ways, and other issues may arise in the transition, so it’s good to be aware of these if you’re contemplating a change.
In industry news, I wrote a sort of meta-post about how the Internet is hard (related: where do you stand on the great Internet vs. internet debate? Comment below!) and we saw several examples of that this month, including a privacy debacle at Florida State University. Marketing is hard, too. I revisited an old post about a fraud case where a woman sued Toyota over an email marketing “prank”. As always, my best practices recommendation for these sorts of things (and everything else!) really boils down to one thing: send wanted email.
Steve wrote extensively about SPF this month in two must-read posts, where he explained the SPF rule of ten and how to optimize your SPF records. He also wrote about Mutt, the much-loved command line email client, and marked the passing of industry pioneer Ray Tomlinson, who, in addition to his many accomplishments, was by all accounts a very thoughtful and generous man.
Finally, I occasionally like to take a moment and follow the twisty paths that lead to my spam folder. Here’s a look at how Ugg spams my email doppelganger, MRS LAURA CORBISHLEY. In other spam news, there’s a lot of very interesting data in the recent 10 Worst list from Spamhaus. Take a look if you haven’t seen it yet.

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Post-mortem on the Spamhaus DOS

There’s been a ton of press over the last week on the denial of service attack on Spamhaus. A lot of it has been overly excited and exaggerated, probably in an effort to generate clicks and ad revenue at the relevant websites. But we’re starting to see the security and network experts talk about the attack, it’s effects and what it tells us about future attacks.
I posted an analysis from the ISC yesterday. They had some useful information about the attack and about what everyone should be doing to stop from contributing to future attacks (close your open DNS resolver). The nice thing about this article is that it looked at the attack from the point of view of network health and security.
Today another article was published in TechWeekEurope that said many of the same things that the ISC article did about the size and impact of the attacks.
What’s the takeaway from this?

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