7 ms·

A rudimentary quantum network link between Dutch cities

082349872349872 2y ago
the article: https://www.science.org/doi/10.1126/sciadv.adp6442 https://www.science.org/doi/10.1126/sciadv.adp6442
ziofill 2y ago
I've worked in quantum nonlinear optics during my first postdoc 12 years ago, and back then we could only dream of the efficiency of frequency conversions that are used here. So many advances in just a decade, and most of them don't even make the news.
- metropolbadger 2y ago
  All those incremental changes is what made my research work indeed. As we described in the paper, the margin we had on amount of signal (dependent also on the conversion efficiency!) was small, so every % of loss anywhere in this chain of photon from emission to detection mattered.
gatkinso 2y ago
Did you hear a cat just now?
qqj 2y ago
[dead]
bawolff 2y ago
What is actually the usecase for "quantum internet"? Like at most i hear about quantum key distribution, but quite frankly the classical equivalents to that are just as good if not better, so what is the actual benefit?
- solarkraft 2y ago
  What are the classical equivalents?
  - danparsonson 2y ago
    Diffie-Hellman?
  - dekhn 2y ago
    manually distributing codebooks of pre-shared keys
- flockonus 2y ago
  I'm curious too! I'd immediately understand if it allows for speed of light communication wireless, but this is clearly wired, requiring more precision engineering than usual fibre.
  - pezezin 2y ago
    What do you mean by "speed of light communication wireless"? Wireless signals (WiFi or similar) are already speed of light.
- ikari_pl 2y ago
  I'd prefer @ziofill to answer, but I think: - security - if we use quantum entanglement/teleportation to the extent I've read about how it works, then even if you still need a fiber optic cable connecting the two parties, the data is unreadable if you're not looking at physically the same wave/photons, meaning that man in the middle attack (like the ones with bending an optic cable to break it's internal reflection) is literally impossible. The data in the middle would not be readable without the receiving end entangled device, and the other side would immediately know about the attack, because an identical signal would not be readable either, as it's not the same signal anymore. - I think the ultimate promise is transferring data without a physical link of any kind in-between. Connect two atoms, manipulate one, read the other - like ansibles in LeGuin/O.S.Card fiction. Instant interplanetary communication (which, I think, fucks up the idea of time too?)
metropolbadger 2y ago
Hi all! I'm one of the co-authors. Honestly it's a dream to end up on HN with my research. As mentioned in the video we made, it has been a long road (6-7 years) to achieve this absolute moonshot of a project. I think we'll look back on this demonstration as the first experiment that truly made a distributed and real-world deployed quantum network. Not only did we use a (quantum) hardware platform capable of quantum processing, we also generated the entanglement in a way that it can be used in further quantum computations. In order for all this to work on a distributed network, we had to fully design and build the architecture to support that, both hard- and software. And we did it successfully! Besides hard-working PhD students, another key ingredient that our research institute QuTech facilitated, was the collaboration with expert hardware and software engineers, allowing us to quickly transform new ideas into (deployable) products. A great show of what's possible when academia mixes with professional engineering. But of course there was enough hacking and tinkering going on that it warrants to be on HN ;) You can reply here if you have any questions, I'll be checking throughout the day. Thanks!
- Havoc 2y ago
  It says over fiber. I assume that has to be a straight shot point to point non-routed? Or could this deal with repeaters and routers etc
  - pclmulqdq 2y ago
    All of the quantum networking stuff is point-to-point. It's not clear to me whether fiber amplifiers are even allowed on these links.
    - dwnw 2y ago
      Amplification would absorb one photon and replace it with one or more new photons. Definitely not quantum. Personally, I always wonder why point-to-point connections are called "networks". The information is not quantum at any node, even if there are multiple nodes in a system. Then there's "quantum internet", which makes no sense at all. What are we going to do, run direct fiber from every computer to every other computer directly? You can't hop safely or anything. Don't get me started on the total bullshit that is the "quantum repeater", now we need "quantum switch" too? We call serial port connections things like "link", "connection", etc. We typically don't call them networks until we start linking them all together with simple routing logic that doesn't inherently require access to all the unencrypted information the packets contain and such. To me these are all just signs that the whole scheme is/was and will forever be mostly crankery. Quantum networking is an oxymoron. It doesn't allow end-to-end encryption and in exchange gives back extremely fragile single link security properties.
deleted 2y ago
[deleted]
dwnw 2y ago
To disperse some of the hype here around using this for "uncrackable" key exchange: QKD has been a product of choice for cybersecurity conmen for decades. https://www.nsa.gov/Cybersecurity/Quantum-Key-Distribution-QKD-and-Quantum-Cryptography-QC/ https://www.nsa.gov/Cybersecurity/Quantum-Key-Distribution-Q... https://www.ncsc.gov.uk/whitepaper/quantum-security-technologies https://www.ncsc.gov.uk/whitepaper/quantum-security-technolo... https://en.wikipedia.org/wiki/Snake_oil_(cryptography) https://en.wikipedia.org/wiki/Snake_oil_(cryptography) Stick with TLS. If you really think quantum computers are a threat to anything, use a hybrid-PQC key exchange. My honest professional opinion is a cryptographically-relevant quantum computer will never exist, making classic cryptography superior in every case.
robblbobbl 2y ago
Good job!
Kon-Peki 2y ago
> “The distance over which we create quantum entanglement in this project, via 25 km of deployed underground fiber, is a record for quantum processors,” says Hanson. “This is the first time such quantum processors in different cities are connected.” I know very little about quantum networking. I assume you are going beyond what they did here? How so? [1] > Recently, as a sort of proof of potential and a first step toward functional quantum networks, a team of researchers with the Illinois‐Express Quantum Network (IEQNET) successfully deployed a long-distance quantum network between two U.S. Department of Energy (DOE) laboratories using local fiber optics. > The experiment marked the first time that quantum-encoded photons — the particle through which quantum information is delivered — and classical signals were simultaneously delivered across a metropolitan-scale distance with an unprecedented level of synchronization. > “To have two national labs that are 50 kilometers apart, working on quantum networks with this shared range of technical capability and expertise, is not a trivial thing,” said Panagiotis Spentzouris, head of the Quantum Science Program at Fermilab and lead researcher on the project. “You need a diverse team to attack this very difficult and complex problem.” [1] https://www.anl.gov/article/quantum-network-between-two-national-labs-achieves-record-synch https://www.anl.gov/article/quantum-network-between-two-nati...

the article: https://www.science.org/doi/10.1126/sciadv.adp6442 https://www.science.org/doi/10.1126/sciadv.adp6442

I've worked in quantum nonlinear optics during my first postdoc 12 years ago, and back then we could only dream of the efficiency of frequency conversions that are used here. So many advances in just a decade, and most of them don't even make the news.

metropolbadger 2y ago
All those incremental changes is what made my research work indeed. As we described in the paper, the margin we had on amount of signal (dependent also on the conversion efficiency!) was small, so every % of loss anywhere in this chain of photon from emission to detection mattered.

gatkinso 2y ago

Did you hear a cat just now?

qqj 2y ago

[dead]

bawolff 2y ago

What is actually the usecase for "quantum internet"? Like at most i hear about quantum key distribution, but quite frankly the classical equivalents to that are just as good if not better, so what is the actual benefit?

solarkraft 2y ago
What are the classical equivalents?
- danparsonson 2y ago
  Diffie-Hellman?
- dekhn 2y ago
  manually distributing codebooks of pre-shared keys
flockonus 2y ago
I'm curious too! I'd immediately understand if it allows for speed of light communication wireless, but this is clearly wired, requiring more precision engineering than usual fibre.
- pezezin 2y ago
  What do you mean by "speed of light communication wireless"? Wireless signals (WiFi or similar) are already speed of light.
ikari_pl 2y ago
I'd prefer @ziofill to answer, but I think: - security - if we use quantum entanglement/teleportation to the extent I've read about how it works, then even if you still need a fiber optic cable connecting the two parties, the data is unreadable if you're not looking at physically the same wave/photons, meaning that man in the middle attack (like the ones with bending an optic cable to break it's internal reflection) is literally impossible. The data in the middle would not be readable without the receiving end entangled device, and the other side would immediately know about the attack, because an identical signal would not be readable either, as it's not the same signal anymore. - I think the ultimate promise is transferring data without a physical link of any kind in-between. Connect two atoms, manipulate one, read the other - like ansibles in LeGuin/O.S.Card fiction. Instant interplanetary communication (which, I think, fucks up the idea of time too?)

metropolbadger 2y ago

Hi all! I'm one of the co-authors. Honestly it's a dream to end up on HN with my research. As mentioned in the video we made, it has been a long road (6-7 years) to achieve this absolute moonshot of a project. I think we'll look back on this demonstration as the first experiment that truly made a distributed and real-world deployed quantum network. Not only did we use a (quantum) hardware platform capable of quantum processing, we also generated the entanglement in a way that it can be used in further quantum computations. In order for all this to work on a distributed network, we had to fully design and build the architecture to support that, both hard- and software. And we did it successfully! Besides hard-working PhD students, another key ingredient that our research institute QuTech facilitated, was the collaboration with expert hardware and software engineers, allowing us to quickly transform new ideas into (deployable) products. A great show of what's possible when academia mixes with professional engineering. But of course there was enough hacking and tinkering going on that it warrants to be on HN ;) You can reply here if you have any questions, I'll be checking throughout the day. Thanks!

Havoc 2y ago
It says over fiber. I assume that has to be a straight shot point to point non-routed? Or could this deal with repeaters and routers etc
- pclmulqdq 2y ago
  All of the quantum networking stuff is point-to-point. It's not clear to me whether fiber amplifiers are even allowed on these links.
  - dwnw 2y ago
    Amplification would absorb one photon and replace it with one or more new photons. Definitely not quantum. Personally, I always wonder why point-to-point connections are called "networks". The information is not quantum at any node, even if there are multiple nodes in a system. Then there's "quantum internet", which makes no sense at all. What are we going to do, run direct fiber from every computer to every other computer directly? You can't hop safely or anything. Don't get me started on the total bullshit that is the "quantum repeater", now we need "quantum switch" too? We call serial port connections things like "link", "connection", etc. We typically don't call them networks until we start linking them all together with simple routing logic that doesn't inherently require access to all the unencrypted information the packets contain and such. To me these are all just signs that the whole scheme is/was and will forever be mostly crankery. Quantum networking is an oxymoron. It doesn't allow end-to-end encryption and in exchange gives back extremely fragile single link security properties.

deleted 2y ago

[deleted]

dwnw 2y ago

To disperse some of the hype here around using this for "uncrackable" key exchange: QKD has been a product of choice for cybersecurity conmen for decades. https://www.nsa.gov/Cybersecurity/Quantum-Key-Distribution-QKD-and-Quantum-Cryptography-QC/ https://www.nsa.gov/Cybersecurity/Quantum-Key-Distribution-Q... https://www.ncsc.gov.uk/whitepaper/quantum-security-technologies https://www.ncsc.gov.uk/whitepaper/quantum-security-technolo... https://en.wikipedia.org/wiki/Snake_oil_(cryptography) https://en.wikipedia.org/wiki/Snake_oil_(cryptography) Stick with TLS. If you really think quantum computers are a threat to anything, use a hybrid-PQC key exchange. My honest professional opinion is a cryptographically-relevant quantum computer will never exist, making classic cryptography superior in every case.

robblbobbl 2y ago

Good job!

Kon-Peki 2y ago

> “The distance over which we create quantum entanglement in this project, via 25 km of deployed underground fiber, is a record for quantum processors,” says Hanson. “This is the first time such quantum processors in different cities are connected.” I know very little about quantum networking. I assume you are going beyond what they did here? How so? [1] > Recently, as a sort of proof of potential and a first step toward functional quantum networks, a team of researchers with the Illinois‐Express Quantum Network (IEQNET) successfully deployed a long-distance quantum network between two U.S. Department of Energy (DOE) laboratories using local fiber optics. > The experiment marked the first time that quantum-encoded photons — the particle through which quantum information is delivered — and classical signals were simultaneously delivered across a metropolitan-scale distance with an unprecedented level of synchronization. > “To have two national labs that are 50 kilometers apart, working on quantum networks with this shared range of technical capability and expertise, is not a trivial thing,” said Panagiotis Spentzouris, head of the Quantum Science Program at Fermilab and lead researcher on the project. “You need a diverse team to attack this very difficult and complex problem.” [1] https://www.anl.gov/article/quantum-network-between-two-national-labs-achieves-record-synch https://www.anl.gov/article/quantum-network-between-two-nati...