September 2014: The Month in Email

September was another busy month for us, but Steve stepped up and wrote a number of really interesting posts on email history, cryptography, and current technical issues in the email landscape.
We started the month with a look at the various RFCs that served as the technical specifications for developing message transfer protocols in the 1970s. It’s really fascinating to look at the evolution of these tools we use every day 40 years later. We followed up with a second post on the origins of network email, which is a great primer (or refresher) on the early days of email.
Steve’s four-part series on cryptography and email started with an in-depth look at how the industry is evolving with respect to encryption and privacy issues. He then introduced us to Alice and Bob (or reintroduced those of us who have been following the adventures of the first couple of cryptography), and described symmetric-key and public-key encryption. His next post described message signing, and how DKIM is used to manage this. He finished up the series with a post on PGP keys.
In industry news: Spamcop is shutting down its email service. There shouldn’t be any major impact on senders, but the post has some specific notes on DMARC implications. We also noted an interesting mail routing suggestion on Twitter, and wrote a post on using Mail.app for this.
In other DMARC news, we wrote about DMARC and report size limits, which might be useful information, depending on your configuration. We also launched a new DMARC tool to help senders understand who is publishing DMARC. Let us know what you think and if you’re finding it useful.
We couldn’t let a month go by without mentioning filters. We looked at a sector we don’t usually discuss, corporate filtering, and went in-depth on a much-misunderstood topic, content filtering.
Finally, Laura offered a webinar on a favorite topic, deliverability, in conjunction with the AMA and Message Systems. If you missed it, you can watch the recorded version here, or just take a peek at some of the reaction via Twitter.

Spamcop mail changes
Marketing pet peeves

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July 2014: The month in email

We continue to be busy with really interesting client work. Look for some new posts and white papers to come out of this research over the next few months, but for now blogging has been a bit light while we’re working hard. In parallel with our busy times, we have also been pondering the ways in which the email world illustrates the classic bon mot  “plus ça change, plus c’est la même chose”, and we’ve been revisiting some posts from a few years ago to examine this.
We started July with a nod to a good subscription experience just as CASL, the Canadian Anti-Spam Legislation went into effect on Canada Day. While companies have another 17 months to put these provisions into practice, it’s a good reminder that periodic re-engagement with customers can be very effective in helping you maintain high-quality subscriber lists. We talked a bit more about CASL here and what protections the law intends.
In stark contrast, we posted about an organization that is doing a less-than-stellar job making sure they’re only sending wanted email. The Direct Marketing Association is a terrific resource and member organization for marketers across industries and channels, but their email marketing practices don’t always live up to their mission of “Advancing and Protecting Responsible Data-Driven Marketing”, and we explored some ways in which they might improve this.
Those of you who have been reading this blog for any time at all know that we tend to talk about wanted mail and unwanted mail rather than the more general category of spam. Marketers tend to think their mail can’t possibly be spam if it’s not offering Viagra or phishing for credit card information, but that’s not really the point — if a customer doesn’t want to read your email about new mountain bikes, even if they bought a mountain bike from you three years ago, that’s unwanted email. Here’s a post we revisited about why customers might not want your mail, and a new post about engagement.
One risk of sending unwanted email, of course, is that customers complain, and that will affect your delivery going forward. We revisited a post about feedback loops, and also talked a bit about addressing delivery problems as they come up rather than waiting for them to resolve on their own (mostly, they won’t!)
I also proposed a bit of a thought experiment around monetizing the complaint stream, and followed up with a second post. There are some good points in the comments of those posts, but mostly I think it’s an interesting solution to addressing risk and abuse at ESPs.
Finally, Steve wrote a short post about our new mail servers and how quickly spammers descended as we set those up. It’s a constant battle!

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Spamcop mail changes

Spamcop is shutting down it’s email service. While anyone could report spam using Spamcop, the system also provided users email addresses behind the Spamcop filters. This shut down should have no major impact on senders. Email addresses in use will still be accepting email, but that mail will simply be forwarded to another address, instead of users being able to access it through POP or IMAP.
The one problem some senders may have is IF they are solely authenticating through SPF and they are publishing a p=reject DMARC statement. This may result in some of the mail being rejected at the forwarding mail server, like AOL, Yahoo and other services respecting DMARC policy statements.
User forwarded mail will be coming from 68.232.142.20 (esa1.spamcop.iphmx.com) and 68.232.142.151 (esa2.spamcop.iphmx.com). If you don’t want to apply DMARC policy to known forwarded mail, those are the IPs to special case.

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How long is your DKIM key?

While we were at M3AAWG, Wired published an article talking about how simple it was to crack DKIM keys. I didn’t post about it at the time because it didn’t really seem like news. DKIM keys smaller than 1024 are vulnerable and not secure and the DKIM spec does not recommend using keys smaller than 1024. When I asked the DKIM-people-who-would-know they did tell me that the news was that the keys had been cracked and used in the wild to spoof email.
Fair enough.
If you are signing with DKIM, use a key 1024 or longer. Anything shorter and your risk having the key cracked and your mail fraudulently signed.
This morning M3AAWG published recommendations on keeping DKIM keys secure.

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