Quote from: cynicSOB on December 18, 2014, 06:38:37 PM

I'll tell you my theories anyway: the two PhDs who wrote that research have a clear nxt bias. Look at their hidden multibranch section: they say that they got 3/20 of 500 blocks with 10% stake. 3/20 of 500 is 75 blocks. They got 75 blocks! if people wait for 6 confirmations, I only need 6 blocks, not 75. So I can do with much less than 10% stake. Of course 10% stake means 10% of actively forging coins, which means 10% of 10% of supply. So, much less than 1% of supply to double spend. Of course that's still a few hundred BTCs for NXT so I'll start with a smaller coin.

I already bought a few coins... just wait until age is accumulated...

Nxt recommends 10 blocks for normal confirmation, 720 to be sure. (There's a rolling check point at 720.)

Generally Nxt has 40-50% forging, so 10% stake means 4-5% of supply.

Quote from: cynicSOB on December 19, 2014, 12:06:38 AM

Sure, thanks. But attacking nxt requires funding that I don't have. I still claim that it can be attacked with less than 10%
NXT may not have age since last transaction, but it has "age" since last block. It accumulates equally to all miners ("forgers"?), but I believe it can be gamed to obtain more than the fair share of probabilities of creating a fork.

I don't know what you're talking about here. Nxt makes newly moved coins wait 1440 blocks before their weight is counted, but after that their weight counts in every block. I don't know what you mean by "age [that] accumulates equally to all miners". The chance of forging a block does not depend on how long it is since the previous block you forged. It depends on what fraction of the forging coins you have.

What is your criteria for a successful attack?