Most users take their e-mail reliability for granted, and if they receive no errors, assume the best. We take a peek under the hood of several providers and explore the service quality of their e-mail service; finding some interesting results in the process. -

"I just sent you an email about that.." or "I never got your email about that.."

Has someone said this before? Of course, the only problems are a) you never did receive their email, and; b) your message to them is sitting in your Sent box. Well, that customer in Cleveland, or your boyfriend or your boss may be telling the truth after all: the email really didn’t arrive. For a long time I trusted my ISP over that customer in Cleveland, but recently I’ve come to believe that my email service is not as infallible as I once believed.

If you want to hear a rosy, glass half-full accounting of email, hit your Internet browser back button.

Who am I?

I am the guy at the dinner party, on the train, at Starbucks, at the grocery store who asks everyone, “is your email service reliable i.e. do you receive every email and in a timely manner? By the way, the results of my unscientific and informal survey are that 95% of respondents tell me “oh yeah, my email is reliable and right as rain.” I am a high-tech marketing guy who has become dependent on email to find job leads, manage receipts, remind me of overdue library books, ask for help on myriad subjects, improve my vocabulary and communicate with customers and employers. I am the guy who needs to know his email is working fine today and will be working fine tomorrow.

Is there no business like show business?

In 2002, so I hear, a Time Warner email administrator lost several days worth of email for nearly 100,000 broadband subscribers in Austin, Texas. I lost an unknown number of business transactions in this gaffe, as well as a couple of job leads and some very important Viagra and penile enlargement offers. Fortunately, I knew about many emails I had not received and asked several colleagues to resend their email; however, I still wonder about the emails I lost that I’ll likely never know about. All I got in terms of resolution? a Time Warner representative telling me, “Mr. Calkins, you have an entertainment account, not a business account.” Translation: email is just about as important as a re-run of “I Love Lucy”.

Although my informal survey tells me there isn’t a problem with email, my anecdotal experience tells me otherwise. So, purely for your and my … entertainment:

1. Email can be lost without a bounce back message to the sender.

2. The timeliness of an email traveling from sender to receiver is unpredictable at best.

3. The reliability and timeliness of an email is directly related to the sending and receiving email providers, and the time of day.

4. Email reliability and delay problems are not limited to ISPs but also exist in IT-managed business email systems.

Are we entertained yet?

Are lost and delayed emails a serious problem? That’s a question for you and how you use email, but I’d say unequivocally yes. If you are dependent upon your ISP’s email server to complete contracts, send RFP responses, exchange notes with that future bride in Russia, communicate timely information with an employee or employer, send invoices, sales orders and receipts, then you should look closely at the reliability of your email service provider.

Email works … well, most of the time it works

The details behind how email works is a bit less than entertaining, but it may explain why two emails addressed to the same user, sent within 3 seconds of each other, could arrive out of order, with the first email arriving a full day after the second.

SMTP (Simple Mail Transport Protocol) is a standard Internet protocol, describing how an email message is sent from one email server to another. SMTP does not describe the process of the sender uploading an email to their ISP, nor the receiver downloading their email. A successful SMTP transaction is:

a) sending server logs into a receiving server

b) sending server waits for the receiving server’s ‘OK’ to transfer an email header and message

c) sending server transfers the email header and message to the receiving server

d) receiving server acknowledges receipt of the email header and message

e) sending server logs off the receiving server

f) If the receiving server reviews the email header and determines the email has reached the final server destination, the final server will hold the email for the user.

g) If the receiving server is NOT the final destination, the server will forward the email to the next server.

An unsuccessful SMTP transaction could be caused by the receiving server being too busy to accept an email message, the sending server timing out, and then temporarily giving up trying to send your email.

Like a customs agent stamping a tourists passport, an email server stamps every email noting the time of receipt and point of entry. And, like every tourist going through New York headed for Disney World, all email does not necessarily follow the same route. Five emails may leave Dulles, Virginia within seconds of each other, bound for a Time Warner email addresses in Austin, but could separately travel through one of the following forwarding servers in: New York, Ohio, Kansas, North Carolina or Florida before arriving in Austin, all at different times.

The truth really IS out there

Because my anecdotal (and entertaining) email experience was not adequate to validate my email conspiracy theory, I’m compelled to provide proof for the reader and the entertainment based ISP.

Email Watch Dog is a monitoring tool that documents how effectively several ISPs manage their email servers, that is, your email. Email Watch Dog is a network of servers that periodically send test emails to test email accounts. The incoming test email headers are read for their historical record of route traveled, servers encountered and time delays experienced.

The Email Watch Dog is currently a network of test email accounts on the following networks:

Cox Broadband – Tulsa

Comcast Broadband – Denver

Earthlink (Bell South) – Atlanta

Time Warner Roadrunner – Austin, Texas

Yahoo

A VERIO network based server in Dulles, Virginia initiates all test emails destined for the test accounts on the above networks.

The following links are graphs representing email server delays accumulated on their trip from Dulles, Virginia to email accounts on Time Warner’s Austin network (xxx@austin.rr.com) and Comcast’s Denver network (xxx@comcast.net). The test emails were broadcast every 5 minutes for 24 hours, from the Dulles server location. The 24-hour time span is plotted on the x axis of the graph, and the y axis represents the time delay an email server adds to an email. The two graphs plot (links) email server delays from Dulles, VA to the two following destinations:

Austin on Time Warner

Denver on Comcast

After reviewing the graphs, you can see Comcast inbound email server delays lasted up to two hours but weren’t nearly as entertaining as Time Warner’s 19-hour email delays.

In the future

Email Watch Dog will provide real-time measurement of email server statistics, account for lost emails and expand the number of test email accounts and servers. For now, don’t blindly send or hope to receive a critical email three minutes after it was sent. That time-critical document may not arrive until tomorrow afternoon, or at all.