StarkWare Researchers propose Smart Contracts for Bitcoin With ColliderVM

Researchers at the Weizmann Institute of Science and Sidechain developer StarkWare claim that they have found a way to work around multiple Bitcoin script restrictions.

A recent study has revealed that paperThe new design is said to make it easier for Bitcoin users to deploy complex smart contracts in an efficient manner. It is possible that the new system will also have a vastly improved computing efficiency.

ColliderVM was designed as a protocol to allow stateful computing on Bitcoin. This allows for multi-step processing to be safely executed across multiple transactions. The output of Bitcoin scripts is typically not available to other scripts. This makes complex calculations difficult.

The researchers argue that ColliderVM could allow the use of Scalable Transparent Arguments of Knowledge (STARKs) — a type of zero-knowledge proof — on Bitcoin without requiring consensus-level changes to the network. The architecture could allow Bitcoin to validate complex off-chain computations using minimal on-chain data.

ColliderVM targets Bitcoin limits

Bitcoin blocks can include up to 4,000,000 OPCodes across all transactions. script Can contain as many as 1,000 stack elements. Stateless execution is also a problem because it means each script runs without any memory for previous transactions or state. Complex computations are therefore impractical.

BitVM is a new implementation that was developed in 2023 paper Robin Linus, a researcher at Bitcoin firm ZeroSync, developed a smart contract that allowed complex transactions on Bitcoin. However it required proof of fraud. The fraud proofs, which are cryptographic evidences of a certain transaction or computation being performed incorrectly and possibly leading to corrective measures.

Fraud proof implementation usually requires operators to advance capital for corrective action. BitVM operators advance capital to cover fraudulent transactions. They recover this money once the fraud-proof period has ended.

It is more cost-effective, though still not as efficient, from the computing perspective, than previous systems. Prior implementations relied on cryptographic signatures.Lamport and WinternitzThe resulting code was computationally intensive.

ColliderVM’s drawings from the ColliderScript of November 2024 paper Researchers from StarkWare have developed a new system that combines the work of researchers at Cloudflare (a web service provider) and Blockstream, whose Bitcoin sidechain is being developed. This system uses a collision-based hash commitment to set a challenge for producing an input which, when ran through a cryptographic hash function produces an output that has predetermined features.

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It is much easier for honest users to use this setup than it would be for malicious ones.

But no food or herb

Hashing is a mathematical operation that cannot be reversed and can produce a constant length alphanumeric sequence. The term non-reversible refers to the fact that it’s impossible to run a computation backward to retrieve the original hash data.

The result is an ID that can be used to identify data, but does not contain any data.

This system — somewhat resembling Bitcoin (BTC) mining — requires significantly fewer hash operations compared to BitVM, reducing both script size and processing time. ColliderVM’s researchers say they reduced those operations further by at least 10,000.

They seem to be suggesting that a STARKs based Bitcoin Sidechain is almost feasible with this implementation. This paper is entitled:

“We estimate that the Bitcoin script length for STARK proof verification becomes nearly practical, allowing it to be used alongside other, pairing-based proof systems common today in applications.”

Starks are an acronym for STARKs. ZK-proof The system is known for its scalability, and their trustless nature. (No trusted setup required). ZK-proofs is a cryptographic method that allows the user to verify a certain feature in a data piece without having to reveal its underlying data.

Early ZK-proof devices required a secure one-time setup which relied on “toxic waste” data. Toxic waste could be used to generate fake proofs of identity and forge false signatures. The STARKs are not trustable because they do not depend on this setup.

STARK-proofs require onchain verification scripts which are more efficient than Bitcoin. ColliderVM’s researchers argue that by using their efficient system approach, they are able to create an onchain verifier script for STARKproofs. “nearly practical.”

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Sidechains based on Bitcoin that are trustless?

Bitcoin has become a widely accepted currency. considered the most secure and reliable blockchainIts critics point out that its features are significantly less extensive than many other altcoins. Liquid by Blockstream is one example of a sidechain, which can be trusted.

Andrew Poelstra is the director of Blockstream’s research team and a mathematician. He told Cointelegraph in 2020 that ZK systems would be used. are “one of the most exciting areas of developmentIn the cryptography area. In a paper published in 2014, Cypherpunk (a developer who was cited in Bitcoin’s white paper, and founder of Blockstream) explained that more work was needed Sidechains that use ZK proof-based verification are a great way to add security and trustworthiness to Bitcoin.

Even 10 years from now, the system built on ColliderVM will still be trust minimalized, not trustless. Users would need to have faith that at least some network participants are honest to maintain the proper functioning of the system.

Ben Fisch and Lior Fisch are researchers who worked with Ben-Sasson as co-founder at StarkWare. Ben-Sasson was one of the first developers of STARKs. He has been a long-time advocate for zero-knowledge-proofs as a way to enhance blockchain scalability.

Ben-Sasson, co-founder of StarkWare and a Cointelegraph interviewee recently noted that for a true Bitcoin layer-2 to be possible it would have to include: “the security of Bitcoin itself.” Current solutions are based on economic incentives or trusting signers. Yet, he acknowledged the Lightning Network.

“We should also acknowledge there’s, of course, today, lightning networks, which have the security of Bitcoin.”

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