The Tide Is Turning for Authentication

After sitting through the Email Authentication Summit and reviewing our recent deliverability survey results, we can see the email industry is moving steadily toward authentication for both commercial senders, ISPs, and corporate recipients.

That means if you aren’t like the 24.2 percent of the marketers in our survey who said they’ve already adopted one of the two leading authentication protocols, your email may languish in the bulk folder.

We haven’t quite reached the authenticate-or-perish point, and we might never get there. E-mail security consultant IronPort predicts the adoption rate will level off at 50 percent or so by late 2007.

Still, current statistics for authentication adoption and other deliverability issues show how your email program stacks up against industry benchmarks, maybe even your competitors.

Authentication Up 60 Percent in 12 Months

The Email Senders and Providers Coalition (ESPC) and IronPort released studies recently showing adoption is spreading among both commercial email senders and ISPs, and corporate receivers. This is significant, because it creates what IronPort called the “critical mass needed to propel the standards forward”:

  • 35 percent of all Internet email is authenticated using SenderID framework (SIDF), a protocol identified with Microsoft.
  • 10 percent of all Internet email uses Yahoo-developed DomainKeys Identified Mail (DKIM).
  • 75 percent of all Fortune 100 companies use SIDF for marketing messages; 45 percent use DKIM. (The ESPC estimated it at 70 percent in November 2005.)
  • Although SIDF is more prevalent, DKIM is gaining traction, from less than 1 percent to 10 percent in nine months.
  • 75 percent of marketing- focused email messages use some form of authentication.
  • 31 percent of all email rated by Hotmail’s filter-effectiveness survey group (about 100,000 Hotmail users) has an SPF record. Eighty-five percent of mail marked as “good” passes the SIDF check. Only 1 percent of the “good” email fails the SIDF check.

But not everyone’s on board. In our recent survey, 24.4 percent of marketers said they authenticate email. Over half said they were planning to implement either SIDF (56%) or DKIM (52%), and just under half said they were thinking about it.

Spam Still Floods the Networks

  • 10 of every 12 messages tracked by the Postini Threat Identification Network is spam.
  • 80 percent of global email is “abusive mail,” according to a study by the Messaging Anti-Abuse Working Group, which focuses on spam and phishing (fraudulent) email.
  • 23 percent of global spam came from U.S. servers from January to March 2006, down from half in 2005, according to antivirus company Sophos.
  • 43 percent of all spam, as measured by originating continent instead of servers, comes from China.
  • At the recent E-mail Authentication Summit, representatives from AOL and Microsoft stated 90-95 percent of all inbound email they process is spam.

ISPs Block One E-Mail in Five

Of email tracked by Return Path, 20.5 percent was either blocked or filtered to a bulk folder from July to December 2005. Twenty-one percent was blocked or filtered from January to June 2005, down from the previous year’s high point of 22 percent blocked or filtered.

Non-Delivery Rates by ISP (%)
AOL Hotmail Yahoo EarthLink Gmail MSN NetZero/Juno
Pivotal Veracity 8.3 19.1 13.5 14.7 26.5 19.0 2.6
Return Path 12.4 26.1 15.3 7.8 40.4 24.4 18.8
1. Pivotal Veracity client data is from December 2005 through January 2006.
2. Return Path client data is from July through December 2005.
Source: EmailLabs, 2006

Improved message content and filtering, better list management and hygiene, whitelists, and changes in ISP blocking and filtering protocols most likely account for the decline.

Who Blocks the Most E-Mail?

Deliverability varies wildly among ISPs, according to studies by Lyris, Pivotal Veracity, and Return Path:

  • 91.5 percent was delivered in Q4 2005, Lyris reported in its analysis of gross email deliverability, up from 90.75 percent in Q3.
  • 97.5 percent of email (inbox plus bulk folder) was delivered to users of the top 10 ISPs, while 76.4 percent of email was delivered to the bottom 10’s users.
  • Top 10 ISPs for both gross and inbox delivery in Lyris’ analysis were, in order: PeoplePC, EarthLink, Yahoo, Gmail, USA.NET, Knology, Juno, Road Runner (SoCal), CompuServer, and .Mac.
  • 91.7 percent of AOL-bound email tracked by Pivotal Veracity clients went to the inbox, the highest of six ISPs studied. The others were Yahoo (86.5%), MSN (81%), Hotmail (80.95), and NetZero/Juno (74%). Gmail filtered the most: 18.9%, compared to 0.1% for AOL.
  • Return Path’s top blockers were Excite (42.9%), Gmail (40.4%), Lycos (33.8%), and Adelphia (31%).
  • The most lenient were USA.NET (9.9%), CompuServer (9.4%), .Mac (8.1%), and EarthLink (7.8%).

If you haven’t authenticated your outbound marketing and transactional emails yet with either or both SIDF or DKIM, what are you waiting for? Make that call to the IT team. It will be well worth it.

Until next time, keep on deliverin’.

Want more email marketing information? ClickZ E-Mail Reference is an archive of all our email columns, organized by topic.

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