BLOG

Tag: spf

The feds are deploying DMARC

The US National Cybersecurity Assessments & Technical Services Team have issued a mandate on web and email security, including TLS+HSTS for web servers, and STARTTLS+SPF+DKIM+DMARC for email. It’s … pretty decent for a brief, public requirements doc. It’s compatible with a prudent rollout of email authentication. Set up a centralized reporting repository for DMARC failure and aggregate […]

No Comments

Are they using DKIM?

It’s easy to tell if a domain is using SPF – look up the TXT record for the domain and see if any of them begin with “v=spf1”. If one does, they’re using SPF. If none do, they’re not. (If more than one does? They’re publishing invalid SPF.) AOL are publishing SPF. Geocities aren’t. For DKIM […]

3 Comments

The philosophy of DMARC

We know that legitimate email sent with valid SPF and a DKIM signature often breaks in transit. SPF will fail any time mail is forwarded – via a mailing list, a forwarding service used by the recipient, or just ad-hoc forwarding. DKIM will fail any time the message is modified in transit. That can be obviously […]

No Comments

Tools!

I just added a DMARC validation tool over on tools.wordtothewise.com. You can give it a domain – such as ebay.com – and it will fetch the DMARC record, then explain and validate it. Or you can paste the DMARC record you’re planning to publish into it,  to validate it before you go live. If you’ve not […]

2 Comments

Fun with opinions

Over the last few weeks I’ve seen a couple people get on mailing lists and make pronouncements about email. It’s great to have opinions and it’s great to share them. But they’re always a little bit right… and a little bit wrong. SPF is dead! This came from the new ESP of an experienced mailer. […]

1 Comment

Gmail showing authentication results to endusers

A bit of older news, but worth a blog post. Early in August, Gmail announced changes to the inbox on both the web interface and the android client. They will be pushing authentication results into the interface, so end users can see which emails are authenticated. These are not deliverability changes, the presence or absence […]

No Comments

BT Internet

I’ve been seeing reports for the last few weeks that a lot of folks are having problems getting mail into BT Internet. Many people are reporting the response smtp;554 Message rejected for policy reasons (3.2.2.1) – Please report any problems to BT via the postmaster btinternet.com mailbox and include your sending ip address with an […]

10 Comments

July 2016: The Month in Email

We got to slow down — and even take a brief vacation — in July, but we still managed to do a bit of blogging here and there, which I’ll recap below in case you missed anything. At the beginning of the month, I wrote about email address harvesting from LinkedIn. As you might imagine, […]

No Comments

SPF ?all

The most read post on the blog is Authenticating with SPF: -all or ~all. In fact, it’s in the top 5 posts every single day. We still get comments on it, too. Usually from folks who disagree with my recommendations. I still stand by my recommendations, though. It doesn’t really matter if you choose ~all […]

4 Comments

Don’t just follow the HOWTO

There are so many moving parts to ensure good email deliverability. Email marketers need to know marketing, they need to know email and they need to know design. The technical bits of email can be a challenge to learn, and many folks who write tutorials and How-Tos write them for a different audience than marketers. One […]

2 Comments

Archives