Drivechain is a Bitcoin improvement proposal that aims to scale Bitcoin and add new features using sidechains.
Drivechain could reduce contentious hard fork disputes by moving experiments to sidechains instead of changing layer 1. Without having to modify the main Bitcoin protocol, there is less risk of causing major disputes and splits in the community when adding new features. Drivechain could also support Bitcoin's security budget after the block reward declines by collecting fees from sidechains. As the block rewards diminish over time, transaction fees from high-volume sidechains could replace this revenue source.
The Drivechain implementation has two key parts - hashrate escrows using blind merged mining to secure sidechains, and new blockchain messages to manage sidechain creation/destruction and transfer funds between sidechains and layer 1.
Hashrate escrows use Bitcoin's mining power to arbitrate sidechain disputes, while blind merged mining lets Bitcoin miners secure sidechains without running full sidechain nodes. The new blockchain messages move assets between chains.
Drivechain requires six new blockchain messages to create/destroy sidechains, bridge Bitcoin to sidechains, and return funds from sidechains to the parent chain. These novel message types enable the two-way transfer of Bitcoins between both the chains. They facilitate the locking and unlocking of funds on each blockchain.
Drivechain moves experiments off layer 1 onto sidechains. This avoids contentious layer 1 changes and hard fork disputes that have created disputes over Bitcoin upgrades. Controversial proposals like increased block sizes or privacy features can be tried on sidechains first rather than directly modifying the parent chain. This prevents network splits and loss of network effect.
Moreover, since sidechains don't modify layer 1, bugs or failures are isolated from the Bitcoin base layer. This reduces attack vectors from code changes. Bitcoin remains simple and robust, avoiding new risks from untested sidechain innovations. Failed experiments don't put the main chain at risk.
In addition to these, Drivechain allows new Bitcoin features to be developed permissionlessly on sidechains. These could include smart contracts, higher privacy, additional assets, prediction markets, etc. Almost any major crypto innovation could be implemented safely as a sidechain, benefiting Bitcoin with new capabilities without danger to the base protocol.
Some argue that Drivechain allows miners to steal sidechain funds. With 51% of hash rate, miners could withdraw BTC from sidechains that they did not deposit. This "miner extractable value" critique suggests sidechain assets are less secure than native BTC unless the whole mining industry is trusted.
Opponents believe blind merged mining incentivizes Bitcoin miners to participate in sidechains they don't validate fully. This could further centralize mining in a few mega-pools that can handle multiple chains. Small independent miners may be pushed out, and forced to rely on larger pooling operators. Critics also argue the complexity of Drivechain and sidechains may have unintended impacts, like new attack vectors. There are fears about scam risks, such as fake sidechains designed to steal users' funds. The more complex Bitcoin's ecosystem grows, the more edge cases and vulnerabilities may emerge.
Join the thousands already learning crypto!