One problem is that the core-years for RSA-250 were in 2017 Skylake Xeon single core terms.
If you can rent a dedicated 96-core Epyc for $1/hour (cheap dedicated host), the combination of IPC improvements (>2x) and core count make 7,010 "skylake core-years" cost only $175k, not $5M. On-demand cloud servers (which cost more than $1, maybe $5/hour) probably make the GPU cheaper, but it's closer than the author says.
I think this is the first time an "I made an agent swarm do something" blog post was actually written by a human, what a breath of fresh air.
big_toast
"I estimate that this factorization cost about 4,900 GPU-days, or 13.5 GPU-years, which is about $400k at current market prices"
"factorization ran at no marginal cost on spare or fragmented compute that couldn’t be used for other purposes"
Interesting use of stranded compute.
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brohee
The discussion on the cost of the attack needs an addendum. The lattice sieving part would be free for an an attacker with a big enough botnet or enough cloud computing stolen credentials.
Maybe it could even be practical to run it on browser in parallel to video streaming on a free video site...
mkmk
This is so well written as to be refreshing
bleepblap
Who is Devin and why do they listen to the author?
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rao-v
Devin … now that’s a name I’ve not hear in a long time
One problem is that the core-years for RSA-250 were in 2017 Skylake Xeon single core terms.
If you can rent a dedicated 96-core Epyc for $1/hour (cheap dedicated host), the combination of IPC improvements (>2x) and core count make 7,010 "skylake core-years" cost only $175k, not $5M. On-demand cloud servers (which cost more than $1, maybe $5/hour) probably make the GPU cheaper, but it's closer than the author says.
Recent and related: RSA-260 Factorized - https://news.ycombinator.com/item?id=49546284 - Sept 2026 (77 comments)
Normally we'd downweight a follow-up [1] but this is a good article and arguably adds SNI [2] in its own right.
[1] https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que...
[2] https://hn.algolia.com/?dateRange=all&page=0&prefix=false&so...
I think this is the first time an "I made an agent swarm do something" blog post was actually written by a human, what a breath of fresh air.
"I estimate that this factorization cost about 4,900 GPU-days, or 13.5 GPU-years, which is about $400k at current market prices"
"factorization ran at no marginal cost on spare or fragmented compute that couldn’t be used for other purposes"
Interesting use of stranded compute.
The discussion on the cost of the attack needs an addendum. The lattice sieving part would be free for an an attacker with a big enough botnet or enough cloud computing stolen credentials.
Maybe it could even be practical to run it on browser in parallel to video streaming on a free video site...
This is so well written as to be refreshing
Who is Devin and why do they listen to the author?
Devin … now that’s a name I’ve not hear in a long time