• grue@lemmy.world
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    8 months ago

    Quantum computing can potentially break the public-key encryption used for transmitting messages across the Internet, but the symmetric-key encryption used for storing data on disk is an entirely different thing.

    • virtualbriefcase@lemm.ee
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      8 months ago

      If I vaguely remember, symmetric encryption is more or less halved by quantom computers using the current encryption breaking methods right? That and just the growing computer power IF they continue to grow at a similar rate. 32 bit encryption used to be the military standard, now it’s a joke that a kid’s laptop could break.

      Makes it potentially vulnerable to governments who are dedicated, but as long as the common laptop theif doesn’t have a quantum computer or a generic technical literacy and years to wait and we’re not making enemies with governments we’re all fine regardless.

      • Chobbes@lemmy.world
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        8 months ago

        Yes, with a quantum computer you could hypothetically halve the effectiveness of AES (so AES-256 would be roughly equivalent to AES-128). This would make a 128-bit key fairly weak (and AES-128 is fairly common still)… a 64-bit space can be brute forced on regular computers in a reasonable amount of time. This doesn’t mean it will be cheap or feasible to break 128-bit AES on quantum computers, though. Maybe it can do it in roughly 2^64 computations, but if each operation is slow it still might not be feasible. At least initially it would probably be expensive to crack so hopefully they’d only bother for really targeted stuff.