A controversial scaling proposal activated on bitcoin last night, though it happened quietly.
Bitcoin Improvement Proposal (BIP) 148, the much-discussed user-activated soft fork (UASF) activated at block 478,484 on the bitcoin blockchain, though its code changes were superceded by another proposal designed to disable it.
Sometimes branded as a protest effort, BIP 148 allowed bitcoin’s node operators a way to show their displeasure with miners, who they believed were blocking popular code updates, who they argued should not have a say in such matters.
As such, BIP 148 emerged as perhaps the most controversial way for the network to enact Segregated Witness, one that while influential, never achieved widespread endorsement.
If things had gone differently, users, mining pools, and companies running the BIP 148 nodes would have started rejecting blocks that did not signal support for SegWit yesterday. There’s a chance this would have caused bitcoin to split into two competing assets.
By now, however, fears of a sudden split by way of BIP 148 have been avoided. Thanks partly to a proposal known as BIP 91, bitcoin mining pools were able to rally together before August 1 by locking in SegWit for activation. UASF supporters often argue that mining pools were incentivized to signal for SegWit because they wanted to avoid the activation of BIP 148 for more political reasons.
In this way, BIP 148’s activation importance is arguably more symbolic, marking the avoidance of a split. On the other hand, a miner-activated hard fork (MAHF) that will fork bitcoin is scheduled for later today.