Electronics obsolescence—also known as DMSMS, for
diminishing manufacturing sources and material
shortages—is a huge problem for designers who build
systems that must last longer than the next cycle of
technology. For instance, by the time the U.S. Navy
began installing a new sonar system in surface ships in
2002, more than 70 percent of the system’s electronic
parts were no longer being made. And it’s not just the
military: commercial airplanes, communications systems,
and amusement-park rides must all be designed around
this problem, or the failure of one obsolete electronic
part can easily balloon into a much larger system
failure.

IEEE Spectrum: Trapped on Technology’s Trailing Edge