Skip Navigation: Avoid going through Home page links and jump straight to content

Web Review

[Feature Story]  

Traffic on Mars

Chuck Toporek
Asst. Managing Editor
Web Review

When the Mars Pathfinder Web development team made their preliminary traffic projections, they could see trouble ahead. More traffic than that of the Hale-Bopp site. More traffic than the Shoemaker-Levy site. And to be honest, more traffic than both of them combined.

Now imagine all of that traffic coming in on one day. It might sound incredible, but here's just a taste of what some of the mirror sites experienced on the day that the Mars Pathfinder landed on the surface:

Mirror Site Hits Received
Hawaii Institute for Geophysics and Planetology 500,000
ATT WorldNet's private mirror 500,000
The Australian Commonwealth Scientific and Industrial Research Organisation (CSIRO) 750,000
Denmark and France 1 million each
Ames Research Center 2.5 million
Silicon Graphics, Inc. 10 million
Table 1: Mars Pathfinder Web site mirrors and the amount of traffic received on July 4, 1997. Note: This table represents only a few of the mirror sites as exact data from each was not available at press time.

Mirrors at Cornell University and the Pittsburgh Supercomputing Center were brought to their knees as traffic started hitting them at a rate that was beyond their capacity, which crashed the servers and forced them to be restarted a number of times.

The mirror site in Uruguay, South America, a country that isn't exactly known for a high-volume of Internet users, had over 2.5 million hits in just seven days! Talk about remote access.

However, the most interesting and little known fact about the amount of traffic to the mirror sites comes from France, where the government actually pleaded with computer users to stop accessing the two Mars Pathfinder mirrors. You see, the phone systems in France carry all of the Internet traffic in the country, so when people started visiting the mirror sites at VisuaNet and Le Centre National D'Etudes Spatiales (CNES), they tied up the phone lines and basically disabled the country.

And how did the server at JPL respond? When the initial hits started coming in on July 4, the servers maxed out and more memory had to be brought in to help ease the load. One of the problems was that most people were unaware of the mirror sites, so JPL was taking on ~6 million hits -- which was way over capacity. And since JPL had two dedicated T3 lines feeding their servers, it meant that their problems were solely hardware related.

On July 4, total combined traffic to the Mars Pathfinder mirror sites received approximately 30 million hits. This was a little less than expected, but was still a tremendous number of hits. Over the weekend, traffic dropped, but stayed in the 28-29 million hits/day range. Then came Monday, July 7 when most Americans went back to work after a long holiday weekend. Traffic soared to around 60 million hits and dropped back over the next couple of days to a steady 40-45 million hits per day.

Since the initial barage of traffic, most of the corporate sites have been handling 8-10 million hits per day. The total estimated number of hits received to date is somewhere in the 200-250 million hits for worldwide access.

Back to, Webmastering Mars.

Other articles in the Webmastering Mars series:


Web Review copyright © 1998 Songline Studios, Inc.
Web Techniques and Web Design and Development copyright © 1998 Miller Freeman, Inc.