Bitcoin Could Become a “Multi-Network” Cryptocurrency with New ‘Drivechain’ Sidechain Proposal

Four years ago, a team of developers proposed using sidechains to expand the capabilities of the bitcoin network. Earlier today, that idea became much closer to reality when the sidechain project arrived on testnet.

As spotted by Coindesk, the project is led by Paul Sztorc, director of research at blockchain startup company Tierion. A test version of the code called “Drivechain” was released on testnet earlier today.

Sztorc announced the news on his blog.

The test version is being released nearly three years after the idea for bitcoin sidechains was first conceived in November 2015. The origins of bitcoin sidechains date back even further: in 2014, developers proposed using sidechains to expand the functionality of the bitcoin network. The idea was to compete with Ethereum, which was just rolling out test versions around that time.

Developers proposed bitcoin sidechains to allow the creation of branches on the bitcoin network that would function in a way similar to Ethereum tokens. Cryptoassets in these bitcoin sidechains could be custom-programmed to suit the needs of various applications – similar to how developers create ERC-20 tokens on Ethereum for their decentralized apps.

Bitcoin’s sidechain proposal was led by bitcoin development company Blockstream after being proposed by Sztorc. Over time, the development team started referring to the sidechain project as a “multi-network coin” idea.

Here’s how Sztorc described a “multi-network” bitcoin in a recent blog post:

“If this ‘multi-network coin' idea is found to be viable, it has profound implications for the crypto's most salient problems. Bitcoin would be able to copy, without controversy, any technology, including: larger blocks, Turing-completeness, and ring signatures.”

How Does Drivechain Work?

On September 25, a testnet version of bitcoin’s sidechain concept was released on testnet. This is the first code release for the sidechain concept – so it’s kind of a big deal.

The project overall is called Drivechain, although the dev team is calling the first testnet release TESTDRIVE.

Drivechain’s testnet version features branches showcasing how the code can add additional characteristics in such a way that they would apply only to a portion of the cryptocurrency. It would effectively create a multi-network bitcoin. You could have a reset proof of work algorithm, for example, and one-way replay protection, on certain coins.

Key features of today’s Drivechain launch include:

• New PoW algorithm (with reset difficulty)
• UTXO loader that is much faster than doing an initial chain-sync and also allows for the easy release of other versions (say, for BCH or BTG) while letting developers mint their own testnet coins
• One-way replay protection, which replays all transactions unless owners say otherwise, at which point owners get permanent replay protection; this would force all exchanges to list the new coin in practice while also equalizing transaction fees for miners across chains

Sztorc also uploaded a “usage tour” showing how the testnet implementation can be used to:

• Send BTC From the mainchain to a sidechain
• Use the sidechain (send BTC from ourselves to ourselves)
• Send the sidechain-BTC back to the mainchain

The usage tour tutorial walks you through everything. You can get the source code from Github here.

Will Drivechain Ever Be Added to Bitcoin?

Drivechain is available on testnet. While some wish to add it to the main bitcoin protocol, others think it detracts from the purpose of bitcoin.

Sztorc believes that if Drivechain’s code is added to bitcoin, then it would solve one of the biggest problems on the bitcoin network:

“There would be no need to fight about which features bitcoin ‘should’ have (or over which features ‘define’ bitcoin).”

There’s also a chance that Drivechain could be implemented as a soft fork.

Ultimately, a project like Drivechain would significantly increase the capabilities of the bitcoin network. The protocol is available on testnet today, although it’s unclear if we’ll ever see a sidechain protocol like this implemented into bitcoin in the future.