On 5 November 2013 20:51, <colj@safe-mail.net> wrote:

Possible Solution:
If N amount of blocks built of the same previous block are received within a time frame of T mine on the block with the lowest hash.

Logic:
In order for Alice to pull of this attack she not only has to propagate her blocks first she must also ensure her blocks are of the smallest hash.

Alice would now have to decrease her target to pull of this attack. Since she has a lower target it will take her longer to find a valid block negating her time advantage.

If I understand the issue properly, this seems like a pretty elegant solution: if two blocks are broadcast within a certain period of eachother, chose the lower target. That's a provable fair way of randomly choosing the winning block and would seem like a pretty simply patch.

Drak