That's the entire point of asymmetric crypto, the amount of effort you would need to brute force 2^160 keys is staggering. Even if you made billions of ASIC processors and ran them until the end of time, you probably wouldn't find the funds you were looking for.
This is constantly suggested, and it's always useless. If you could attack keys like this the system would be broken.
It's important to note that asymmetric crypto behaves somewhat differently. RSA is a particularly notable example of this: a 160-bit RSA key is almost trivial to break, 512-bit keys are possible, and there are good reasons to think that large organizations with lots of cash and motivation are able to break individual 1024-bit keys when they want to.
The ECDSA keys used in Bitcoin are much stronger than RSA keys at the same size, and they seem quite safe, but don't make the mistake of looking at the time needed to brute force e.g. a 128-bit AES key and assume that applies to asymmetric algorithms too.
No. What the GP is quoting is "security bits" a measure explicitly designed to mitigate that difference. Bitcoin addresses have 160 bits of security, 128 bits if the public key is known. This is directly comparable to symmetric key sizes.
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That's the entire point of asymmetric crypto, the amount of effort you would need to brute force 2^160 keys is staggering. Even if you made billions of ASIC processors and ran them until the end of time, you probably wouldn't find the funds you were looking for.
This is constantly suggested, and it's always useless. If you could attack keys like this the system would be broken.
It's important to note that asymmetric crypto behaves somewhat differently. RSA is a particularly notable example of this: a 160-bit RSA key is almost trivial to break, 512-bit keys are possible, and there are good reasons to think that large organizations with lots of cash and motivation are able to break individual 1024-bit keys when they want to.
The ECDSA keys used in Bitcoin are much stronger than RSA keys at the same size, and they seem quite safe, but don't make the mistake of looking at the time needed to brute force e.g. a 128-bit AES key and assume that applies to asymmetric algorithms too.
No. What the GP is quoting is "security bits" a measure explicitly designed to mitigate that difference. Bitcoin addresses have 160 bits of security, 128 bits if the public key is known. This is directly comparable to symmetric key sizes.
Thanks for clarifying that. The mismatch between the key size quoted and what's used in Bitcoin should have tipped me off.