Probability that two different files can have same MD5 hash for both an unencrypted and encrypted version (AES256, same key between files)
This math is way over my head, and don't even know if it can be done, but here are the assumptions: Take unencrypted File [Fu] of variable length, but assume 100KB as an example. Let File [Fe] be ...
Hashcash is a proof-of-work system in which the Sender needs to find $Y$ such as the first (let's say 20) bits of $H(X+Y)$ are zeros where $H$ is a one-way hash function, $X$ is a fixed value and $+$ ...
I have such requirements to the hash function in my project: operating on 32-bit data, not mathematically breakable (built on existing hashes known to be secure), free of branching, as much as ...
In reading about the Bitcoin protocol I noticed how much its proofs-of-work apparently depend on uniformity of the SHA-256 hash function. And so presumably do many other applications. How do ...