BOX 3.1 on September 11, 2001

September 11, 2001, has certainly not been the only high-demand period experienced by Internet news sites. For example, interest in the results of the 2000 general election fueled a steep rise in demand. But September 11 set new records, and consequently the ability to reach major news Web sites that day was reduced for some people.1

To use this experience to better understand the demands on news servers during a crisis event and to identify measures that can help deal with that demand, a representative from CNN’s Internet division was invited to participate in the workshop held by the Committee on the Internet Under Crisis Conditions. Key elements of CNN’s experience follow.

On September 11, CNN’s overall demand surged greatly, with the measured daily load (as expressed in page views) increasing on September 11 to 132 million— nearly 10 times the more typical load of 14 million on September 10. The measured demand of September 11 probably underestimates total user demand, however, because not all users were able to successfully load the Web page as the demand initially surged after the crash of the first airplane. The number of hits (pages or images requested) doubled every 7 minutes, resulting in an order-of-magnitude increase in less than 30 minutes. Demand for news continued to grow in the hours following the attack, with the load on September 12 reaching 304 million page views—more than twice that measured on September 11.

Keeping up with demand after the first airplane crash was very challenging for the CNN operations staff, who employed a combination of several techniques to deal with the load:

  • Reducing Web page complexity. The main Web page was significantly reduced in size (i.e., as measured by the number of separate elements such as

reported that “Nostradamus,” “cnn,” and “World Trade Center” were the top three terms among people whose search-engine usage increased during the week ending September 13.14

The Internet as a Means of Communicating Between Individuals

On September 11, many people felt the need to communicate right away with family, friends, and colleagues. The purpose of these communications ranged from emergency responses (as officials in New York


Google. 2002. “Google Search Statistics from 9/11/01,” Google, Mountain View, Calif. Available online at <>.

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