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Title: Thoughts on the security of bitcoins? Post by: jz87 on January 17, 2013, 10:54:35 AM So I was just wondering how secure bitcoins are now that quantum computers are starting to become commercially available.
http://en.wikipedia.org/wiki/D-Wave_Systems#D-Wave_One_quantum_computer_system Title: Re: Thoughts on the security of bitcoins? Post by: RaTTuS on January 17, 2013, 11:05:51 AM q-computing wont do anything for or against bitcoins
... YMMV Title: Re: Thoughts on the security of bitcoins? Post by: tbcoin on January 17, 2013, 11:46:49 AM (facepalm)
Please, first read: https://bitcointalk.org/index.php?topic=131778.0 https://bitcointalk.org/index.php?action=search2&search=quantum edit: We have covered this topic many times before. Quantum computing is not a threat to Bitcoin in any reasonable timeframe. Does this need to be in the FAQ? It's a 128-qubit machine. If you have to ask the price, that means you can't afford it (nor program it). It requires a specially built facility to house it. From Proos and Zalka (2008): http://arxiv.org/pdf/quantph/0301141.pdf (http://arxiv.org/pdf/quantph/0301141.pdf) Quote We show in some detail how to implement Shor’s efficient quantum algorithm for discrete logarithms for the particular case of elliptic curve groups. It turns out that for this problem a smaller quantum computer can solve problems further beyond current computing than for integer factorisation. A 160 bit elliptic curve cryptographic key could be broken on a quantum computer using around 1000 qubits while factoring the security-wise equivalent 1024 bit RSA modulus would require about 2000 qubits. In this paper we only consider elliptic curves over GF(p) and not yet the equally important ones over GF(2^n) or other finite fields. The main technical difficulty is to implement Euclid’s gcd algorithm to compute multiplicative inverses modulo p. As the runtime of Euclid’s algorithm depends on the input, one difficulty encountered is the “quantum halting problem” Bitcoin uses the secp256k1 elliptic curve. This means 256-bit keys on a Koblitz curve. The p means prime field, GF(p). The NSA informs us that a 256 bit elliptic curve key is equivalent to a 3072 bit RSA modulus. (http://www.nsa.gov/business/programs/elliptic_curve.shtml) Therefore 1000 qubits is nowhere near close enough to solve even much weaker keys than the one Bitcoin uses, and the D-Wave machine provides only 128. Even assuming quantum computers get much cheaper over time, you're not going to have a cryogenically cooled room sized machine in your house any time soon. And even if one day this becomes possible, there are several mitigating factors:
Title: Re: Thoughts on the security of bitcoins? Post by: tunafish on January 17, 2013, 08:53:32 PM Meh, i'm not too good with the technical details but from what i've gathered over the years it seems like the possible problems would be more from those who could disrupt the blockchain but even then that'd take alot of power and bandwidth and is more of a dick move than anything. "Stealing" or somehow creating bitcoins seems impossible or close to it (excluding user related mistakes/exploiting human nature)
Maybe some kind of trojan style exploit that would have to be spread through a bt client or market (some poker/gambling site that uses flash/java or requires users to download anything) that would be scripted to funnel coins to a set address? I'm sure along the way some users will figure out ways to fuck things up but given how good the track record has been so far I'm optimistic. Title: Re: Thoughts on the security of bitcoins? Post by: b!z on January 18, 2013, 07:29:21 AM Meh, i'm not too good with the technical details but from what i've gathered over the years it seems like the possible problems would be more from those who could disrupt the blockchain but even then that'd take alot of power and bandwidth and is more of a dick move than anything. "Stealing" or somehow creating bitcoins seems impossible or close to it (excluding user related mistakes/exploiting human nature) Maybe some kind of trojan style exploit that would have to be spread through a bt client or market (some poker/gambling site that uses flash/java or requires users to download anything) that would be scripted to funnel coins to a set address? I'm sure along the way some users will figure out ways to fuck things up but given how good the track record has been so far I'm optimistic. Malicious / hijacked websites exist, and have always existed. It's your responsibility to protect yourself. Title: Re: Thoughts on the security of bitcoins? Post by: oliviancool on January 18, 2013, 03:00:05 PM Meh, i'm not too good with the technical details but from what i've gathered over the years it seems like the possible problems would be more from those who could disrupt the blockchain but even then that'd take alot of power and bandwidth and is more of a dick move than anything. "Stealing" or somehow creating bitcoins seems impossible or close to it (excluding user related mistakes/exploiting human nature) Maybe some kind of trojan style exploit that would have to be spread through a bt client or market (some poker/gambling site that uses flash/java or requires users to download anything) that would be scripted to funnel coins to a set address? I'm sure along the way some users will figure out ways to fuck things up but given how good the track record has been so far I'm optimistic. Malicious / hijacked websites exist, and have always existed. It's your responsibility to protect yourself. Right, no one can guarantee that you will be fine and your bitcoins are secured, you don't know that. |