Related, this was just published today: <a href="http://voxelsoft.com/dev/sumcoin.pdf" rel="nofollow">http://voxelsoft.com/dev/sumcoin.pdf</a>
> A commitment scheme lets you keep a piece of data secret but commit to it so that you can not change it later.<p>> commitment = SHA256( binding_factor || data )<p>> Tell someone the commitment, then [later] reveal both the data and blinding factor.<p>It looks like I can change my data, then generate a binding factor that will combine to produce the original hash input.
This is related to:<p><a href="https://news.ycombinator.com/item?id=9684066" rel="nofollow">https://news.ycombinator.com/item?id=9684066</a>