Cryptographic Accumulator
I’ve been following this thread that mostly boils down to this: if I have the SHA-256 hash of a file, can I use that to get a file from IPFS? The short answer is not really?, because Merkle-DAG.
The slightly-longer answer is that because Merkle-DAG is required to allow chunking files and verifying those chunks as they come in, and SHA-256 does not have a facility to combine hashes of two components into a single hash for the combined block, you can’t find files on IPFS my the hash of the entire file in a way where you can verify that each block belongs to that hash without having to download the entire file.