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Grad Student Solved a Fundamental Quantum Computing Problem

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Re: Grad Student Solved a Fundamental Quantum Computing Problem

#11

Post by zamadatix »

d3andj wrote: post #9

I sincerely believe we should treat quantum computing discoveries as (long term) major 0-days, as in they should sent in confidentiality to sensitive sectors's actors, those that depend heavily on classic encryption.

Or perhaps if it is believed we are close to making a quantum computer that can easily break classic cryptography we simply assume it's broken instead of waiting for the first person who wants to tell us publicly? I don't see why quantum research should be held up more than any other area when it comes to zero days. If we are going to trust people to be forthcoming I think we can trust them to decide if it should be sensitively announced.

Re: Grad Student Solved a Fundamental Quantum Computing Problem

#12

Post by demygale »

Schiphol wrote: post #10
killjoywashere wrote: post #7

The lack of inspectability, it seems to me, would make quantum computing flat-out unacceptable in a variety of problem domains, including pretty much any decision support system. Not theoretically, so much as socially. In the way nuclear reactors are unacceptably risky to many who accept a far higher death toll associated with roofers falling to their deaths installing solar. Sure nuclear saves lives, but my aunt doe…

I have a B. Eng. in chemical engineering, unlike "your auntie" I understand nuclear plenty, and still think, with most everyone else educated and uneducated alike, it's MUCH more dangerous than solar.

I’m a big proponent of nuclear energy. The benefits far outweigh the risks. But solar power has never rendered an area of the planet uninhabitable, so I understand the concern.

Re: Grad Student Solved a Fundamental Quantum Computing Problem

#13

Post by chasingthewind »

killjoywashere wrote: post #7

The lack of inspectability, it seems to me, would make quantum computing flat-out unacceptable in a variety of problem domains, including pretty much any decision support system. Not theoretically, so much as socially. In the way nuclear reactors are unacceptably risky to many who accept a far higher death toll associated with roofers falling to their deaths installing solar. Sure nuclear saves lives, but my aunt doe…

I think it's quite "rational" to find nuclear power far scarier than rooftop solar. The tail risk of nuclear power is Fukushima. I'm not even sure what the tail risk of rooftop solar would be. The average case outcome between these two isn't compelling for me.

Re: Grad Student Solved a Fundamental Quantum Computing Problem

#14

Post by Fuzzy_Logic »

demygale wrote: post #12
Schiphol wrote: post #10

Earlier quoted context omitted.

I have a B. Eng. in chemical engineering, unlike "your auntie" I understand nuclear plenty, and still think, with most everyone else educated and uneducated alike, it's MUCH more dangerous than solar.

I’m a big proponent of nuclear energy. The benefits far outweigh the risks. But solar power has never rendered an area of the planet uninhabitable, so I understand the concern.

Solar panels do come at an environmental cost, particularly in developing economies with little environmental regulation.

https://sinosphere.blogs.nytimes.com/2014/06/02/chinas-solar...

Re: Grad Student Solved a Fundamental Quantum Computing Problem

#15

Post by [deleted] »

cyrux004 wrote: post #5
throwawaymath wrote: post #4

Mahadev's result is excellent by any standard and remarkable for a graduate student. It's both impressively creative and technically novel. But quantum verification has not been solved, and the headline is wrong. In essence, Mahadev developed a quantum verification protocol that relies on a post-quantum secure cryptosystem. She used an encryption scheme based on the the Learning With Errors (LWE) problem, which is on…

what do you do mr. throwaway ?

[deleted]

Re: Grad Student Solved a Fundamental Quantum Computing Problem

#16

Post by amarant »

chasingthewind wrote: post #13
killjoywashere wrote: post #7

The lack of inspectability, it seems to me, would make quantum computing flat-out unacceptable in a variety of problem domains, including pretty much any decision support system. Not theoretically, so much as socially. In the way nuclear reactors are unacceptably risky to many who accept a far higher death toll associated with roofers falling to their deaths installing solar. Sure nuclear saves lives, but my aunt doe…

I think it's quite "rational" to find nuclear power far scarier than rooftop solar. The tail risk of nuclear power is Fukushima. I'm not even sure what the tail risk of rooftop solar would be. The average case outcome between these two isn't compelling for me.

still, if you count lives lost per kwh produced, nuclear is the safest source of energy around. that's gotta count for something

wish i had a better source handy, but this forbes article will have to do for now: https://www.forbes.com/sites/jamesconca/2012/06/10/energys-d...

Re: Grad Student Solved a Fundamental Quantum Computing Problem

#17

Post by 3pt14159 »

zamadatix wrote: post #11
d3andj wrote: post #9

I sincerely believe we should treat quantum computing discoveries as (long term) major 0-days, as in they should sent in confidentiality to sensitive sectors's actors, those that depend heavily on classic encryption.

Or perhaps if it is believed we are close to making a quantum computer that can easily break classic cryptography we simply assume it's broken instead of waiting for the first person who wants to tell us publicly? I don't see why quantum research should be held up more than any other area when it comes to zero days. If we are going to trust people to be forthcoming I think we can trust them to decide if it should be…

If you listen to natsec or intelligence Podcasts you'll hear these people stressing over quantum. We need quantum proof algorithms today, not ten years from now. For symmetric encryption this is easy, unfortunately the vast majority of our encryption protocols bootstrap with PKI.

I've come to the view that because we have a physical safety problem with cyber now (cars, drones, etc) we should be shipping devices with hardware enforced one time pads and the update procedure should incorporate them with a layered approach (ie, encryption + OTP).

Yes physical security is hard and OTPs shouldn't be used most places, but if the factories or update servers for Tesla are physically owned we're fucked anyway so we already have a physical security problem. Why solely trust in cryptographers that have routinely underestimated the risk of algorithmic or side-channel breach? I really want my mind to be changed here, because I don't like having opinions that are way outside the mainstream, but no matter how I dice it I don't see why we shouldn't be employing OTPs.

Re: Grad Student Solved a Fundamental Quantum Computing Problem

#18

Post by amelius »

d3andj wrote: post #9

I sincerely believe we should treat quantum computing discoveries as (long term) major 0-days, as in they should sent in confidentiality to sensitive sectors's actors, those that depend heavily on classic encryption.

Except QC breaks only public key systems. Sensitive actors can just use secret keys to transmit information.

Re: Grad Student Solved a Fundamental Quantum Computing Problem

#19

Post by rocqua »

3pt14159 wrote: post #17
zamadatix wrote: post #11

Earlier quoted context omitted.

Or perhaps if it is believed we are close to making a quantum computer that can easily break classic cryptography we simply assume it's broken instead of waiting for the first person who wants to tell us publicly? I don't see why quantum research should be held up more than any other area when it comes to zero days. If we are going to trust people to be forthcoming I think we can trust them to decide if it should be…

If you listen to natsec or intelligence Podcasts you'll hear these people stressing over quantum. We need quantum proof algorithms today, not ten years from now. For symmetric encryption this is easy, unfortunately the vast majority of our encryption protocols bootstrap with PKI. I've come to the view that because we have a physical safety problem with cyber now (cars, drones, etc) we should be shipping devices with…

Presuming you mean One Time Pads, they are an exagerated solution. If I want to send you 1GB of data, we should not require 1GB of shared secret random data.

A setup where you have e.g. 4kb of shared secret data, and use that to communicate fully randomly generated keys. Then those keys are used with symmetric encryption for the full transaction.

The main issue with this is the 'shared secret' part. How would you do 'code signing' with an OTP? You'd need a shared secret with the developer. The developer can't possibly have a different shared secret with each user, and even if they could, it would mean that every user would need a different signature on their binary. So instead, there is one secret shared with everyone.

But if Alice, Bob, and the Dev all have access to the shared secret, then Alice doesn't know whether Bob or the Dev made the signature. This can partially be solved by secure enclaves, but if you have the same secret on a million secure enclaves, it becomes feasible to extract that secret. Besides, it seems quite probably that secure enclaves also have side-channels.

Asymmetric cryptography doesn't have this issue, because you don't rely on a user having only partial access to some data. For many interactive things, a 'chain' of shared secrets could probably be used to set up a secure channel. But for off-line usage such as attestations or proofs of authorization, that isn't possible.

PKI does suck, but the biggest issue is authenticating keys, not the use of weak algorithms.

Re: Grad Student Solved a Fundamental Quantum Computing Problem

#20

Post by 3pt14159 »

rocqua wrote: post #19
3pt14159 wrote: post #17

Earlier quoted context omitted.

If you listen to natsec or intelligence Podcasts you'll hear these people stressing over quantum. We need quantum proof algorithms today, not ten years from now. For symmetric encryption this is easy, unfortunately the vast majority of our encryption protocols bootstrap with PKI. I've come to the view that because we have a physical safety problem with cyber now (cars, drones, etc) we should be shipping devices with…

Presuming you mean One Time Pads, they are an exagerated solution. If I want to send you 1GB of data, we should not require 1GB of shared secret random data. A setup where you have e.g. 4kb of shared secret data, and use that to communicate fully randomly generated keys. Then those keys are used with symmetric encryption for the full transaction. The main issue with this is the 'shared secret' part. How would you do…

Yes, I didn't capitalize it, but I did spell out OTPs in my original post.

Here's the part where CompSci people lose me:

> If I want to send you 1GB of data, we should not require 1GB of shared secret random data.

I agree if the data is something trivial like video but it doesn't follow to me that OTPs shouldn't be used for something as critical as code updates for autonomous vehicles control systems.

> How would you do 'code signing' with an OTP?

We don't take anything away. We don't discard our normal cryptographic methods of encryption and code signing. We simply layer them. That way if the cryptographic method is flawed, or the keys compromised, an attacker would also need to compromise the OTP.

Just as structural engineers layer their defences for structural collapse, I fail to see how introducing a OTP presents a serious burden to autonomous device makers compared to the stakes involved. It makes class-attacks far less relevant because the OTPs would need to be breached too.

Even if our OTPs were solely used for the cryptographic signature (as opposed to the whole encrypted code update) we would still be leagues better in the event of a compromise. I know we shouldn't need to, but mistakes keep happening. I know we shouldn't trust physical security over cryptographic security, but if we're layering them how does it hurt?

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