July 17, 1997
Human Error Cripples the Internet
By PETER WAYNER
“Tens of millions of people are using the Internet, and very few of them know how truly complex it is.” Adam Clayton Powell 3d,
The Freedom Forum
Alex Gadea, the President of Vscape International, a Web site hosting company, was among the hundreds of systems people rousted out of bed Thursday morning when server alarms started going off around the world. Gadea's company pays a private service to check his 10 main Web servers every 10 minutes and beep him if they fail to respond. The beeps started at 5:30 in the morning.
The problem occurred when the database of the top level domain name server (DNS) became corrupted. This database acts as the telephone book for the Internet, matching names like e-mail addresses and Web URLs to four-byte numbers known as IP (for Internet Protocol) addresses, which steer data through the Internet to the appropriate computer.
For instance, the name "www.nytimes.com" corresponds to nine different computers that answer requests for The New York Times on the Web, one of which is 199.181.172.242. This four-byte address is used by the Internet in a manner roughly analogous to a nine-digit zip code to direct packets of information directly to the correct computer.
Each day at 2:30 a.m., Network Solutions updates its directory, known as a "lookup table," to reflect the changes made during the day. These include adding new addresses for anyone who has registered a new domain name and deleting addresses for sites than have surrendered their names. Network Solutions also shuts down the names of entities that haven't paid the $100 fee required to register the name.
In this case, the database became corrupted when it was regenerated, effectively wiping out all of the more than one million companies in the .com and .net domains. The .edu, .gov and .org domains, which are also administered by Network Solutions were not affected.
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