I’m still waiting on an XKCD that references #936 with the fact that we soon as we have reliable, functional quantum computing, all of the passwords from before that point in time will be completely and utterly broken. That the only way to make a password that a quantum computer would have a tough time breaking is if it was made by another quantum computer. Unless of course the comic has already been made and I just missed it, which is a complete possibility because this year for me has been utterly crap.
Some of them are broken by quantum computers, but not all of them. For example, SHA256. You can use Grover’s algorithm to take sqrt(n) steps to check n possible passwords, which on the one hand means it can be billions of times faster, but on the other hand, you just need to double the length of the password to get the same security vs quantum computers. Also, this is the first I’ve heard of a hash that uses a quantum computer. Do you have a source? Hashes need to be deterministic, and quantum computers aren’t, so that doesn’t seem like it would work very well.
Maybe you’re getting mixed up with using quantum encryption to get around quantum computers breaking common encryption algorithms?
soon as we have reliable, functional quantum computing
Which we’ve been told is right around the corner for decades. The issue is that QC doesn’t scale up. If you try you get vastly more noise than signal. Current work in QC is all aimed at reducing that noise, but even for only 70 qbits, the current state of the art can’t eliminate enough of the noise for QC to be useful in most applications.
The only places it’s currently bearing any fruit is where all of the extra work to reduce noise and the delays that incurs are irrelevant because there is no classical approach at all. But even then, the costs are enormous and the benefits are miniscule.
For today’s 10,000 who have never seen it, https://xkcd.com/936/ succinctly explains why the whole mixed character types thing isn’t favoured.
I’m still waiting on an XKCD that references #936 with the fact that we soon as we have reliable, functional quantum computing, all of the passwords from before that point in time will be completely and utterly broken. That the only way to make a password that a quantum computer would have a tough time breaking is if it was made by another quantum computer. Unless of course the comic has already been made and I just missed it, which is a complete possibility because this year for me has been utterly crap.
Some of them are broken by quantum computers, but not all of them. For example, SHA256. You can use Grover’s algorithm to take sqrt(n) steps to check n possible passwords, which on the one hand means it can be billions of times faster, but on the other hand, you just need to double the length of the password to get the same security vs quantum computers. Also, this is the first I’ve heard of a hash that uses a quantum computer. Do you have a source? Hashes need to be deterministic, and quantum computers aren’t, so that doesn’t seem like it would work very well.
Maybe you’re getting mixed up with using quantum encryption to get around quantum computers breaking common encryption algorithms?
Which we’ve been told is right around the corner for decades. The issue is that QC doesn’t scale up. If you try you get vastly more noise than signal. Current work in QC is all aimed at reducing that noise, but even for only 70 qbits, the current state of the art can’t eliminate enough of the noise for QC to be useful in most applications.
The only places it’s currently bearing any fruit is where all of the extra work to reduce noise and the delays that incurs are irrelevant because there is no classical approach at all. But even then, the costs are enormous and the benefits are miniscule.
Except you can run a dictionary attack on that and suddenly it’s only 4 variables that are cracked way faster than the first password.
Except you can run a dictionary attack on that and suddenly it’s only 4 variables that are cracked way faster than the first password.