DKIM and DomainKeys, Spam and Ham

I’ve been preaching “DKIM is great! DomainKeys is obsolete, get rid of it!” for several years now. I thought I’d take a look at my mailbox and see who was using authentication.
I’ve divided this into “Ham” and “Spam”. Spam is, well, all the spam I’ve received over the past couple of years. Ham is the non-spam mail in my inbox, whether personal, business, bulk or transactional. I’ve excluded most of the discussion mailing lists I’m on (not least because many of them consist of people in the email industry or are email standards development mailing lists, so have email authentication levels that are way outside the norm).

Spam and Ham

 
Most legitimate mail – between 50% and 70% – is authenticated using DKIM, but signing levels seem fairly steady, with maybe a slight upward trend. Very little spam is authenticated at all. DomainKeys usage is pretty low, and seems to be gradually declining.
The end result isn’t terribly surprising, but having hard numbers is mildly interesting.
 

Related Posts

Spamming to hide fraud

An interesting article at NetworkWorld last month, describing spam bombs to victims of fraud and identity theft to hide the transactions and notifications from financial institutions.

Read More

Bad Neighborhoods on the Internet

Of the 42,000 Internet Service Providers (ISPs) surveyed, just 20 were found to be responsible for nearly half of all the internet addresses that send spam.

Read More

Troubleshooting tools

There have been a number of comments on my post about Hotmail moving to SPF authentication having to do with troubleshooting authentication failures. I have been helping clients troubleshoot these issues, and am able to take on new clients to solve authentication problems. Contact me for more information.
Of course, many of these issues can be solved with access to the right tools. Steve’s been working on a number of tools that may help the troubleshooting process and we’ve recently launched them on Emailstuff.org. The website itself contains a number of DNS and data related tools we use for investigations and thought we’d share with the public at large.
One of the really useful tools is the SPF record expander. Plug in any domain, like google.com, and see what IP addresses they authorize to send mail.

Read More