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Legacy problems

Across the computing industry, we spend enormous amounts of money and effort on keeping older, legacy systems running. The examples range from huge and costly to small and merely annoying: planes circle around in holding patterns burning precious fuel because air traffic control cant keep up on systems that are less powerful than a smartphone; WiFi networks dont reach their top speeds because an original 802.11(no letter), 2Mbps system could show up—you never know. So when engineers dream, we dream of leaving all of yesterdays technology behind and starting from scratch. But such clean breaks are rarely possible.

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