Essays Tagged "Computer Language"
Page 1 of 1
Doing it Randomly: Probabilistic Algorithms in Programming
The approach to using probability algorithms is a powerful and innovative way to solve sharing problems.
It may seem strange that programming, which has long been a bastion of exact algorithms behaving in precisely the same manner every time, occasionally turns to probability to solve some of its more difficult problems.
In some people’s minds, algorithms should be proveably correct at all times and for all inputs (as with defect-free programming and formal methods). Probabilistic algorithms give up this property. There is always a chance that the algorithm will produce a false result. But this chance can be made as small as desired. If the chance of the software failing is made smaller than the chance of the hardware failing (or of the user spontaneously combusting, or whatever), there’s little to worry about…
Sharing Secrets Among Friends
Whether you're protecting a nuclear missile or your new recipe for burger sauce, polynomial encryption can prevent people from stealing your secrets.
Let’s say you’ve invented a new, extra-gooey, extra-sweet, creme filling; or a burger sauce that is even more tasteless than before. This stuff is important; you have to keep the recipe secret. You can tell only your most trusted employees the exact mixture of ingredients, but what if one of them defects to the competition? Before, long every grease palace on the block would be making burgers as tasteless as yours. That just wouldn’t do.
You can take a message and divide it up into secure pieces. Each of the pieces by itself means nothing, but put them all together and the message appears. If each employee has a piece of the recipe, then only together can they make the sauce (employees could type their portion into a central sauce-making computer or something). If any employee jumps ship with a piece of the recipe, the portion is useless by itself…
Sidebar photo of Bruce Schneier by Joe MacInnis.