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flux@microsoft.com |
| Douglas Boling |
| TerraServer |
When you go to the TerraServer Web site at http://www.terra-server.com, you’re presented with a map of the world with most of the U.S. and western Europe covered in green dots. The green indicates areas of the earth’s surface that TerraServer has pictures of in its database. Clicking on a spot on the map generates a new zoom-in map covering that part of the world. As you keep zooming in, the image changes from a map to actual satellite photographs. Those photos can then be zoomed in up to the maximum resolution of the image. Each image is composed of tiles of separate images that the database engine pulls from the terabytes of data in the TerraServer database. You can click on the borders of the image presented to pan to the images surrounding it. Once you’ve found the location
You can also search for cities or natural features by name. The search results provide hyperlinks to the images for that location. You can also use a short list of famous places to jump to immortal sites like the U.S. Capitol, the Eiffel Tower, and of course, Microsoft’s Redmond campus. The pictures come from two sources. The U.S. Geological Survey has a database of images that covers about 30 percent of the United States. The pictures have a resolution of 1 meter, meaning that each pixel in an image covers 1 square meter. The other source of images is Sovinformsputnik, the Russian space agency. Their data is satellite images that cover parts of the U.S. and other major population centers around the world. The Soviet data isn’t as detailed as the USGS images, with only a 1.6 meter resolution. That kind of resolution lets you see cars, but not individual people. The hardware that drives this site include a Compaq AlphaServer 8400 and a StorageWorks storage system. The AlphaServer is powered by eight 440MHz DEC Alpha processors and has 10GB of RAM. This isn’t your father’s PC. The system has 324 9GB drives for a total capacity of 2.9 terabytes. There are also enough tape drives and RAID controllers to make an IS manager giggle with delight. All the hardware provides impressive if not lightning fast performance. The tiled images are delivered to your browser in seconds. Not bad when you consider the amount of data that has to be sifted through just to get the correct image. If I have a complaint about the site, it’s the age of the images. The USGS images are from 1988, while the Soviet data was generated in 1992-94. This doesn’t matter if you’re looking for geographical data, but it makes it too old if you’re looking for recent improvements on, say, a city block. Still, the site is nothing if not fun to browse. Everyone I’ve seen use the site initially looks for an image of their house, then starts checking out famous places. This is a seductive site. It’s not every day you get to look down on Hong Kong’s harbor or the Golden Gate Bridge. You have to approach TerraServer on two levels. First and foremost, TerraServer is a marketing instrument. Its goal is clearly to show off Microsoft’s high-end server products. The site has plenty of information on how you, the IS professional, can use Microsoft products to solve your problems. At another level the system is a rather expensive but very public stress test of both the hardware and software. The nonimaging pages of the TerraServer site are festooned with trademarks from the companies that have contributed hardware to the site. Some of the TerraServer pages remind me of the pit row at a NASCAR race. Since its inception, the automobile industry has competed in racing—not to make money, but for R&D. Testing designs under the stressful conditions of racing reveals unknown weaknesses in design. The TerraServer site can be approached in the same manner; by placing a massive database of images on the Web, where users will randomly look up images of home or workplace, both the hardware and software of the TerraServer site is rigorously tested. Just as automotive companies recover some of their cost in advertising, so are the folks providing the tools for the TerraServer site. While the site is great for Microsoft and its hardware partners, the question is how valuable is it to the user? Well, just how valuable is a NASCAR race? Something must be attracting folks to NASCAR—it’s the largest spectator sport in the U.S. I don’t think TerraServer will achieve that sort of popularity, but it’s a fun site nonetheless. 
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