3 ms·

More details: https://x.com/sweis/status/2101484464807596264 https://x.com/sweis/status/2101484464807596264 I had Claude port CADO-NFS to run on GPUs. Then

by madars 12d ago

More details: https://x.com/sweis/status/2101484464807596264 https://x.com/sweis/status/2101484464807596264 I had Claude port CADO-NFS to run on GPUs. Then it orchestrated a fleet to run on scavenged idle capacity. It ran with a max of 2048 GPUs for about of 30 GPU-years over 10 days. I asked Claude if it had a message for a public: “The credit belongs first to the people who built the number field sieve and CADO-NFS over several decades, and to the teams who set the earlier records. This run used their algorithm and much of their code.” Also to clarify: - No new algorithmic factoring improvements. - It’s still exponential. - No new threats to deployed keys.

sjs382 12d ago
https://xxcancel.com/sweis/status/2101484464807596264 https://xxcancel.com/sweis/status/2101484464807596264
wslh 12d ago
> It’s still exponential It's actually subexponential: https://en.wikipedia.org/wiki/General_number_field_sieve?wprov=sfti1#Method https://en.wikipedia.org/wiki/General_number_field_sieve?wpr...
- cwillu 12d ago
  …but super-polynomial.
  - schoen 12d ago
    Like in the song! https://www.metzdowd.com/pipermail/cryptography/2004-June/007114.html https://www.metzdowd.com/pipermail/cryptography/2004-June/00...
    - homosapien97 12d ago
      Thanks for sharing, that brightened my day
    - aidenn0 12d ago
      When's the coming age of crypto-anarchy?
      - schoen 12d ago
        Not sure! It sounded more imminent back in 2000 when I heard Eric Hughes perform the song.
- sweis 12d ago
  I misspoke and corrected down thread.
deleted 12d ago
[deleted]
DavideNL 12d ago
More details: https://archive.li/20260920025515/https://x.com/sweis/status/2101484464807596264 https://archive.li/20260920025515/https://x.com/sweis/status...
whizzter 12d ago
10 days of 2048 GPU's. Back of the envelope.. 1024 bit keys with recordings of not too old data can probably be found (MS only deprecated them in 2024 even if they planned on it in 2013) How long would it take for NSA to crack them if they had say the equivalent of a million GPU's? (either GPU's or crypto tuned ASICs)
- walrus01 12d ago
  A sufficiently motivated person with a good thermal camera and a cessna 172, entirely within the bounds of the law, could probably make an estimate of the waste heat from this, and then calculate backwards for how much compute power it is. https://en.wikipedia.org/wiki/Utah_Data_Center https://en.wikipedia.org/wiki/Utah_Data_Center
  - maqp 11d ago
    Except that's the "Massive Data Repository" which is mostly just about hoarding mass surveillance data. (Unless of course that's what THEY want us to think!) A better approximation can probably be had by comparing against the performance of the top ones at https://top500.org/ https://top500.org/
- ErroneousBosh 12d ago
  > How long would it take for NSA to crack them if they had say the equivalent of a million GPU's? (either GPU's or crypto tuned ASICs) Something I've often wondered is where the curve between "shit encryption / nation state cracking" crosses. How much CPU would you need to be Annoyingly Difficult to crack? I reckon with elliptic curves you could be quite annoying within about a minute on a 1980s-level CPU, to the extent that you could send a fairly ephemeral message quite quickly that would take disproportionately long to crack. Certainly long enough for the thing you have communicated to be no longer worth the effort to know. You could probably do 256-bit Curve25519 key generation in under ten minutes on an Apple II or Commodore 64, because the 6502's maths is terribly limited, but something like the Tandy Color or Dragon 32 with its 6809 processor (or hey why not the Ensoniq Mirage sampler?) could do that in probably a minute or so because it has a MUL opcode that's quite fast. I reckon that would keep even a fairly interested nation state chewing away long after your message had been read, understood, and acted upon.
deleted 12d ago
[deleted]
weinzierl 12d ago
What does "scavenged idle capacity" mean here?
- JoshTriplett 12d ago
  The author works at Anthropic, so probably idle capacity in Anthropic's datacenters.
  - bradfa 12d ago
    If so, then the class of GPU used here may be significantly higher than mere mortals generally have access to simply due to cost. Obviously nation states will likely have significantly more resources than this, but this is not script kiddie levels of GPUs.
  - gosub100 12d ago
    "idle capacity" - aka subtle advertisement
- dgacmu 12d ago
  If you look at the numbers, he managed about 50% utilization of those 2048 GPUs over 10 days, so he was probably sneaking in factoring work between training runs.
charlieyu1 12d ago
I've done a fair amount of heavy computing now. Integer factorisation is not something you can really improve with GPUs. This sounds extremely wasteful, a bunch of cheap CPU cores would do just as well with much lower hardware cost and electricity cost.
- saidnooneever 12d ago
  but we have AI now so it doesnt matter what people know about computers :'). we got plenty of rainforest to burn afterall have you seen Brazil?
- timcobb 12d ago
  ~so then how does one even understand this post? you have a person who appears to have done some sort of expert-level thing; however, their approach doesn't even make sense...?~ edit: GPU discussed here https://cognition.com/blog/factoring-rsa-260 https://cognition.com/blog/factoring-rsa-260
- hughw 12d ago
  I don't get your argument. The GPU effectiveness derives from massive parallelism. Has nothing to do with integer vs floating point. You just can't cram 20,000 CPU cores in the same space a GPU puts the same number of SIMTs. You'll never crack it on CPUs.
bertonvv 12d ago
It seems that Eric Lu at Cognition AI used the exact same strategy on fewer GPUs to factor RSA-260 a couple weeks ago: https://cognition.com/blog/factoring-rsa-260 https://cognition.com/blog/factoring-rsa-260 Devin (their AI agent) ported CADO-NFS to run on GPUs, similarly without any claimed algorithmic factoring improvements, they just let it run for 13 GPU-years. I recommend reading their article since it's much more thorough on details.
- thesz 12d ago
  34 bits of key growth resulted in resource usage growth slightly more than 2 (30 GPU-years vs 13.5 GPU-years). Thus, it appears, that ~585 GPU years can factor 1024 bit RSA. 2.2^((1024-896)/34)=19.5, expected growth of resources' usage compared to 896 bits factorization, multiplying it by 30 GPU years for 896 bits gives about 585 GPU-years. This will cost about $20M with Cognition AI setup.
  - maqp 11d ago
    That's a relatively expensive strategy to get your name on Wikipedia.
- sweis 11d ago
  Yep, they ran on some newer GPUs so were able to use fewer. Their implementation was faster than mine on RSA-260. For RSA-896, mine improved the performance a bit and selected a good polynomial. I’ll post more details once I get a chance. I wanted to publish as soon as I had the factors because I was beat by 48 hours last time.
jgalt212 12d ago
> I had Claude port CADO-NFS to run on GPUs. Then it orchestrated a fleet to run on scavenged idle capacity Is it easier to find unused GPUs than unused CPUs?

by madars 12d ago

sjs382 12d ago

https://xxcancel.com/sweis/status/2101484464807596264 https://xxcancel.com/sweis/status/2101484464807596264

wslh 12d ago

> It’s still exponential It's actually subexponential: https://en.wikipedia.org/wiki/General_number_field_sieve?wprov=sfti1#Method https://en.wikipedia.org/wiki/General_number_field_sieve?wpr...

cwillu 12d ago
…but super-polynomial.
- schoen 12d ago
  Like in the song! https://www.metzdowd.com/pipermail/cryptography/2004-June/007114.html https://www.metzdowd.com/pipermail/cryptography/2004-June/00...
  - homosapien97 12d ago
    Thanks for sharing, that brightened my day
  - aidenn0 12d ago
    When's the coming age of crypto-anarchy?
    - schoen 12d ago
      Not sure! It sounded more imminent back in 2000 when I heard Eric Hughes perform the song.
sweis 12d ago
I misspoke and corrected down thread.

deleted 12d ago

[deleted]

DavideNL 12d ago

More details: https://archive.li/20260920025515/https://x.com/sweis/status/2101484464807596264 https://archive.li/20260920025515/https://x.com/sweis/status...

whizzter 12d ago

10 days of 2048 GPU's. Back of the envelope.. 1024 bit keys with recordings of not too old data can probably be found (MS only deprecated them in 2024 even if they planned on it in 2013) How long would it take for NSA to crack them if they had say the equivalent of a million GPU's? (either GPU's or crypto tuned ASICs)

walrus01 12d ago
A sufficiently motivated person with a good thermal camera and a cessna 172, entirely within the bounds of the law, could probably make an estimate of the waste heat from this, and then calculate backwards for how much compute power it is. https://en.wikipedia.org/wiki/Utah_Data_Center https://en.wikipedia.org/wiki/Utah_Data_Center
- maqp 11d ago
  Except that's the "Massive Data Repository" which is mostly just about hoarding mass surveillance data. (Unless of course that's what THEY want us to think!) A better approximation can probably be had by comparing against the performance of the top ones at https://top500.org/ https://top500.org/
ErroneousBosh 12d ago
> How long would it take for NSA to crack them if they had say the equivalent of a million GPU's? (either GPU's or crypto tuned ASICs) Something I've often wondered is where the curve between "shit encryption / nation state cracking" crosses. How much CPU would you need to be Annoyingly Difficult to crack? I reckon with elliptic curves you could be quite annoying within about a minute on a 1980s-level CPU, to the extent that you could send a fairly ephemeral message quite quickly that would take disproportionately long to crack. Certainly long enough for the thing you have communicated to be no longer worth the effort to know. You could probably do 256-bit Curve25519 key generation in under ten minutes on an Apple II or Commodore 64, because the 6502's maths is terribly limited, but something like the Tandy Color or Dragon 32 with its 6809 processor (or hey why not the Ensoniq Mirage sampler?) could do that in probably a minute or so because it has a MUL opcode that's quite fast. I reckon that would keep even a fairly interested nation state chewing away long after your message had been read, understood, and acted upon.

deleted 12d ago

[deleted]

weinzierl 12d ago

What does "scavenged idle capacity" mean here?

JoshTriplett 12d ago
The author works at Anthropic, so probably idle capacity in Anthropic's datacenters.
- bradfa 12d ago
  If so, then the class of GPU used here may be significantly higher than mere mortals generally have access to simply due to cost. Obviously nation states will likely have significantly more resources than this, but this is not script kiddie levels of GPUs.
- gosub100 12d ago
  "idle capacity" - aka subtle advertisement
dgacmu 12d ago
If you look at the numbers, he managed about 50% utilization of those 2048 GPUs over 10 days, so he was probably sneaking in factoring work between training runs.

charlieyu1 12d ago

I've done a fair amount of heavy computing now. Integer factorisation is not something you can really improve with GPUs. This sounds extremely wasteful, a bunch of cheap CPU cores would do just as well with much lower hardware cost and electricity cost.

saidnooneever 12d ago
but we have AI now so it doesnt matter what people know about computers :'). we got plenty of rainforest to burn afterall have you seen Brazil?
timcobb 12d ago
~so then how does one even understand this post? you have a person who appears to have done some sort of expert-level thing; however, their approach doesn't even make sense...?~ edit: GPU discussed here https://cognition.com/blog/factoring-rsa-260 https://cognition.com/blog/factoring-rsa-260
hughw 12d ago
I don't get your argument. The GPU effectiveness derives from massive parallelism. Has nothing to do with integer vs floating point. You just can't cram 20,000 CPU cores in the same space a GPU puts the same number of SIMTs. You'll never crack it on CPUs.

bertonvv 12d ago

It seems that Eric Lu at Cognition AI used the exact same strategy on fewer GPUs to factor RSA-260 a couple weeks ago: https://cognition.com/blog/factoring-rsa-260 https://cognition.com/blog/factoring-rsa-260 Devin (their AI agent) ported CADO-NFS to run on GPUs, similarly without any claimed algorithmic factoring improvements, they just let it run for 13 GPU-years. I recommend reading their article since it's much more thorough on details.

thesz 12d ago
34 bits of key growth resulted in resource usage growth slightly more than 2 (30 GPU-years vs 13.5 GPU-years). Thus, it appears, that ~585 GPU years can factor 1024 bit RSA. 2.2^((1024-896)/34)=19.5, expected growth of resources' usage compared to 896 bits factorization, multiplying it by 30 GPU years for 896 bits gives about 585 GPU-years. This will cost about $20M with Cognition AI setup.
- maqp 11d ago
  That's a relatively expensive strategy to get your name on Wikipedia.
sweis 11d ago
Yep, they ran on some newer GPUs so were able to use fewer. Their implementation was faster than mine on RSA-260. For RSA-896, mine improved the performance a bit and selected a good polynomial. I’ll post more details once I get a chance. I wanted to publish as soon as I had the factors because I was beat by 48 hours last time.

jgalt212 12d ago

> I had Claude port CADO-NFS to run on GPUs. Then it orchestrated a fleet to run on scavenged idle capacity Is it easier to find unused GPUs than unused CPUs?