He told you so: Jon Postel (1943 – 1998)

One of the internet's first architects, Jon Postel, helped launch the first ARPAnet connection in 1969 as a Ph.D. student at UCLA. At the time, ARPAnet was restricted to research sites and funded under the federal Advanced Research Projects Agency.

In 1975, Postel published a paper for ARPAnet's ad-hoc Network Working Group. Numbered RFC 706, Postel's essay was more memorably titled "On the Junk Mail Problem." In it, he identified an Achilles heel in the architecture that would eventually be used to build the Internet:

"In the ARPA Network Host/IMP interface protocol there is no mechanism for the Host to selectively refuse messages. This means that a Host which desires to receive some particular messages must read all messages addressed to it. Such a Host could be sent many messages by a malfunctioning Host. This would constitute a denial of service to the normal users of this Host. Both the local users and the network communication could suffer. The services denied are the processor time consumed in examining the undesired messages and rejecting them, and the loss of network thruput or increased delay due to the unnecessary busyness of the network."

Postel's proposed solution has, over the years, proved easier said than done. "It would be useful for a Host to be able to decline messages from sources it believes are misbehaving or are simply annoying."

Of course, it probably never occurred to Postel -- or to anyone else in 1975 -- that e-mail's vulnerabilities would be exploited not by malfunctioning computers but by direct-marketing entrepreneurs.

When the U.S. government opened up the Internet to commercial use in 1995 -- a year after the law firm Canter & Siegel launched the first big spam campaign on Usenet -- Postel's "junk mail problem" took on a whole new meaning. As did everything else on the Net, leading to lawsuits against Postel by businesses dissatisfied with his role in assigning Internet domain names and address numbers. In the '70s, designing for more than four billion Internet addresses had seemed ample overkill.

Six years after Postel's death, the fight over who controls the Internet continues to grow almost as rapidly as the volume of spam. Last fall, the United Nations attempted to seize control of the Internet Assigned Numbers Authority, which had once consisted mostly of Jon Postel. RFC 706 is now a museum piece, a nostalgic artifact of an earlier, noncommercial Net on which most problems were, well, academic.