Bitcoin Forum

Miner authors can implement simple detection routine that will stop mining if pool jumps back for more than a 5 blocks (checking by the hash of previous block).
This will make ">50%" attack much more difficult to accomplish.

There is also another vulnerability to cover - the block holding, this may me the next task for miners.
By doing this, at least all honest miners can be sure that their pool is not trying to make a fork.

Overtaking the pools or pool owners to disrupt the blockchain will be useless if the protection will be implemented in the miner software.

good idea

This would be like a 6-blocks-back block chain lock-in.  Maybe not a bad idea at this point (unlike the early days when legitimate users might throw lots of new hashing power at the network or there might have been network splits because there were so few nodes).

I think there would have to be an override, in case there WAS an hour or two or three network split.

Or maybe some attempt to detect double-spends (e.g. more-than-5-block-split OK if all transactions are valid on both chains).

This is interesting. Every miner would have be a node if I understand correctly.

No, it's much more simple. You don't have to be a node to count five hashes back.

what about this?
https://forum.bitcoin.org/index.php?topic=9137

For implementing this, you'll need to convince all the pool's owners to replace their software. And it will not stop others from creating "classic" pools.

My solution is compatible with all existing pools and doesn't requres pool author's cooperation.