A Warning On Deliverability

A new study is a warning to ISPs that they may be blocking more than they know.

by Alex Goldman ISP-Planet Managing Editor [April 14, 2005]

The fact that it discloses all of the data elements as well as the source of its data makes the first ever e-mail deliverability report from Lyris particularly useful. Berkeley, Calif.-based Lyris Technologies provides e-mail services for large corporations and for mail-intensive operations like our own ISP-Lists.

Responding to clients' concerns about whether e-mail was actually being delivered, the company commissioned a research report [.pdf].

It set up dummy e-mail accounts at 41 ISP and e-mail Service Provider (ESP) domains in the United States and Europe to track opt-in (but not double opt-in, a procedure familiar to ISP-List participants) campaigns.

Even the best e-mail provider, SpamCop, failed to deliver 2.7 percent of the 556 e-mails sent to dummy SpamCop accounts. The worst e-mail provider failed to deliver a full 26.5 percent of 616 e-mails. Google's gmail erroneously delivered 16 percent into the spam folder, but the worst offender in that category, cnc.net (Concentric—nowadays part of XO) filtered 61.7 percent of 559 e-mails into the spam folder.

Shannon Coulter, Lyris marketing manager and also the person who took charge of the report, said the company felt it needed to know what was happening with e-mail. "We're hearing more and more from clients and customers that deliverability is an issue for them. We're concerned that while ISPs are getting more zealous about fighting spam, every ISP does it differently, and it's very difficult to keep track of how each ISP does it."

Of all the anti-spam solutions Coulter fears, the one she fears the most is the one we at ISP-Planet have always recommended more than any other solution. We have favored the solutions that filter out spammy connections, like that of TurnTide (now part of Symantec).

Lyris does not like this solution to the spam problem. "If you send out 50,000 legitimate e-mails to a popular ISP, and that ISP notices you are hitting its servers over and over, the ISP will start blocking that e-mail," notes Coulter.

"A more effective way of fighting spam is to do a Bayesian filter, which is what the higher deliverability service providers do. Lyris software is designed to be fast, but when we have to slow down our e-mail to one per connection, that speed is not put to good use."

To conclude the interview, we asked Coulter what Lyris service the report could be selling. "If we're going to be accused of selling anything, it's the e-mail advisor tool which is how we monitor e-mail," she replied.

She noted that Lyris intends to produce an e-mail deliverability report every quarter.

Perhaps every ISP should, if they can, run their own e-mail deliverability test.

It's 2005. Do you know what you're blocking and filtering?

— End