Bitcoin split on Aug. 8 when BIP-110's mandatory signaling kicked in at block 961632, but the minority chain has only managed to mine two blocks since. Nodes enforcing the rule change started rejecting blocks that didn't comply, and now the chain's backers are debating a proof-of-work algorithm reset to keep it moving.
The split at block 961632
BIP-110 required miners to signal support for the change starting at block 961632. When the block arrived, nodes running the new rules began rejecting blocks that didn't carry the mandatory signal. That effectively created two chains: the main Bitcoin chain, which continues to operate as before, and a minority chain that follows BIP-110's rules.
The split wasn't a surprise — the proposal had been known for months. But the speed with which the minority chain has stalled is notable.
Two blocks and a stall
So far, the minority chain has mined just two blocks. Bitcoin's difficulty — the mechanism that adjusts how hard it is to find a block — is calibrated for the main chain's hash rate. On the minority chain, with far less hash power, that difficulty makes mining nearly impossible. Activity has effectively come to a crawl.
That's a problem for anyone hoping to use the new chain. Two blocks is barely a start, and without a steady stream of blocks, transactions can't confirm reliably.
Debating a PoW reset
Now, proponents of BIP-110 are discussing whether to change the proof-of-work algorithm on the minority chain. The proposed reset is aimed at 'firing' Bitcoin miners — that is, making the existing ASIC hardware used for Bitcoin mining obsolete on the new chain, so it can attract different miners or at least function without the main chain's hash rate.
Changing the PoW algorithm is a significant technical decision. It would mean the minority chain no longer uses the same mining hardware as Bitcoin, which could be a way to break the difficulty deadlock. But it's also a departure from the original BIP-110 design, and it's unclear whether the proponents can reach consensus.
