Asked by: Claire Nichol, London
If our data is in the cloud, the answer is that we don’t know where it is. Our files will be spread across data centres anywhere in the world. Because most cloud providers back up the data across multiple sites, then the chances are your files exist simultaneously in more than one place, possibly across different countries or continents. Your bits and bytes might, for instance, find their way to a data centre like the massive facility at 350 East Cermak in Chicago, reputedly the biggest such storehouse in the world. It occupies a former printer’s and telephone exchange that houses storage and processing equipment over an area of 100,000m2. The servers have a cumulative capacity of 3,000 years’ worth of uncompressed video. But that kind of storage is energy hungry, too. The Chicago facility consumes 100MW. In that part of the world, its electricity bill is second only to O’Hare airport.
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