On Tue, Feb 04, 2014 at 04:17:47PM +0100, Natanael wrote: > Because it's trivial to create collisions! You can choose exactly what > output you want. That's why XOR is a very bad digest scheme.
You're close, but not quite. So, imagine you have a merkle tree, and you're trying to timestamp some data at the bottom of the tree. Now you can successfully timestamp the top digest in the Bitcoin blockchain right, and be sure that digest existed before some time. But what about the digests at the bottom of the tree? What can an attacker do exactly to make a fake timestamp if the tree is using XOR rather than a proper hash function? -- 'peter'[:-1]@petertodd.org 000000000000000075829f6169c79d7d5aaa20bfa8da6e9edb2393c4f8662ba0
signature.asc
Description: Digital signature
------------------------------------------------------------------------------ Managing the Performance of Cloud-Based Applications Take advantage of what the Cloud has to offer - Avoid Common Pitfalls. Read the Whitepaper. http://pubads.g.doubleclick.net/gampad/clk?id=121051231&iu=/4140/ostg.clktrk
_______________________________________________ Bitcoin-development mailing list Bitcoin-development@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/bitcoin-development
