BIP 102 (2MB Block Size)
A short-lived proposal to increase Bitcoin's block size to 2 MB, reflecting earlier scaling contention.
BIP 102, drafted by Jeff Garzik in 2015, was the smallest possible scaling proposal: change the maximum block size from 1 MB to 2 MB at a fixed flag-day height. No witness discount, no soft fork tricks, just a hard fork to a slightly larger block.
It never activated. The community settled on SegWit (BIP 141) instead, which delivered an effective 1.7-2x capacity increase as a soft fork, fixed transaction malleability, and unlocked the Lightning Network. Big-block proponents who wanted a clean capacity bump (and rejected SegWit on principle) forked off as Bitcoin Cash in August 2017.
Almost a decade later, the answer to "how does Bitcoin scale" hasn't changed: SegWit and Taproot for base-layer efficiency, Lightning for high-throughput payments, and a deliberate refusal to chase throughput by inflating the block. BIP 102 is the road not taken, and a useful reference for why the road wasn't taken.
Spec: BIP-102.
Key takeaways
- A direct block size doubling proposal
- Never implemented due to consensus around SegWit
- Reflects the early, heated scaling disputes