x86 Virtual Machine (Qtum)

What Is an x86 Virtual Machine?

An x86 virtual machine (VM) is a virtualized environment that emulates the x86 architecture, allowing the execution of programs and software for the x86 instruction set.

The Qtum project has developed an x86 VM designed explicitly for executing smart contracts in various programming languages.

Similar to the Ethereum Virtual Machine (EVM), the Qtum x86 VM enables the execution of smart contracts, but with some notable enhancements:

  • Flexibility in Smart Contract Development: Unlike the Ethereum VM, which primarily supports Solidity, the Qtum x86 VM allows developers to write smart contracts in multiple programming languages with a just-in-time (JIT) compiler. This includes languages like C++, Java, Python, and others commonly used in application development. This provides dApp developers with more choices and flexibility in developing smart contracts.
  • Multiple Pricing Models: In addition to the gas model used in Ethereum, where users pay for each operation executed in a smart contract, Qtum introduces two new pricing models. These include a fixed fee per transaction and a fee per transaction, offering alternative options for transaction cost calculation.
  • Enhanced x86 Support: The Qtum x86 VM supports x86 registers and memory operations using a unified 16-bit instruction encoding scheme. This design reduces gas costs in common cases compared to the Ethereum VM, enabling more efficient execution of operations per transaction and potentially increasing throughput on the Qtum blockchain.

What Is Qtum?

Qtum is an open-source blockchain project that aims to combine the stability of Bitcoin with the flexibility of Ethereum.

It was founded by the Qtum Foundation, headquartered in Singapore, in 2016 and launched its mainnet in 2017.

Qtum combines several key elements to achieve its goals:

  • Bitcoin Core: Qtum builds upon the robustness and security of the Bitcoin Core codebase.
  • Proof-of-Stake Consensus: Qtum employs a proof-of-stake consensus mechanism, which is more energy-efficient than Bitcoin’s proof-of-work and reduces the risk of centralization.
  • Ethereum Virtual Machine (EVM): The EVM allows developers to execute smart contracts on the Qtum blockchain, providing compatibility with Ethereum’s ecosystem.

Qtum also implements a Decentralized Governance Protocol (DGP), allowing dynamic blockchain parameter adjustments without hard forks.

This ensures the blockchain remains functional even in the face of changes or upgrades.

Qtum’s UTXO transaction model enables faster transaction processing, while still supporting the execution of smart contracts.