Who's Sending Email? Ask IronPort

Joe St Sauver, Ph.D.
Director, User Services and Network Applications
joe@uoregon.edu

Have you ever wondered who are the biggest senders of email on the Internet? IronPort Systems can help answer that question on their website at http://senderbase.com/

We looked at IronPort's site on May 27th. Some of the top senders for the 24 hours preceding that date are domains that would hardly surprise anyone: yahoo.com is in first place with approximately 679 million messages per day, with Hotmail next at approximately 375 million messages per day.

Other well known top-sender domains included attbi.com (349.2 million), rr.com(305 million), aol.com (252 million), and comcast.net (233.7 million).

But some of the other top senders are more surprising:

• online-shop-exchange.com, part of VMX Inc., has an estimated daily volume of 314.1 million. Add to that the 288.6 million associated with shoppersville.net, also part of VMX Inc., and the total, an estimated 602.7 million messages per day, would put this particular sender second only to yahoo.com in terms of total message volume.

  To put these numbers in context, if you wanted to deliver 600 million messages per day, you would be required to deliver over 6900 messages per second, around the clock. That's a lot of email!

• ew01.com, which is part of WholesaleBandwidth, Inc., sent an estimated 94.6 million messages during a 24-hour period on May 26.
• dartmail.net, part of Doubleclick, Inc., sent an estimated 92.8 million messages in one 24-hour period.

The InPort Systems website also lists the top senders by IP address.

All in all, this is a fascinating site if you're trying to understand what's being sent in terms of email traffic volumes.