EVM stands for in blockchain
A virtual machine (VM), most notably the Ethereum Virtual Machine (EVM), is a safe and separated runtime environment for code execution in the context of blockchain, especially for platforms like Ethereum. It can be thought of as a computer emulator.
The following summarizes of the virtual machines (VMs), with an emphasis on EVM:
Purpose and Role of EVM
- A virtual machine (VM) is an essential component of a smart contract system that runs the code on the blockchain network’s nodes.
- Its main goal is to make it possible for Turing complete code to execute on a blockchain, enabling sophisticated programs called smart contracts that are not possible with simpler, more constrained transaction scripts.
- The purpose of the EVM is to enable safe execution of untrusted code over a worldwide public blockchain-based operating system.
- Because of its complete isolation and sandboxing, the programs that runs on it is unable to access external resources like a disc or network. Deterministic execution is ensured and security is increased by this isolation.
- The EVM offers a strong defence against security risks like as data manipulation and denial-of-service assaults. It can protect the computer it runs on by making sure that nothing undesirable occurs when code is executed.
Structure and Operation of EVM
- A low-level stack-based assembly, commonly known as EVM assembly, is carried out by the EVM.
- Usually written in high-level languages like Solidity, smart contracts are turned into executable bytecode that the EVM can comprehend. The blockchain has this bytecode.
- The EVM is a straightforward stack-based execution machine that changes the state of the system by executing bytecode instructions. Key-value storage and a memory byte array are features of this stack-based interpreter.
- ECC computations and the Keccak 256-bit hash are made possible by the EVM’s word size being set to 256 bits. The stack is based on a Last In, First Out (LIFO) queue and can contain up to 1024 pieces.
- Arithmetic, logic, control flow, and Ethereum-specific functions like accessing memory and storage or checking the balance of Ethereum are all covered by the EVM’s opcodes.
- Although the EVM is Turing-complete, the amount of gas needed to execute instructions limits how well it can execute. This gas requirement mitigates denial-of-service attacks by preventing infinite loops and serving as a cost for computation and storage.
- Because code execution is entirely deterministic, conforming implementations will all produce identical state transitions from identical initial states.
- If the machine halts due to defects, like insufficient gas or erroneous instructions, the EVM can handle exceptions.
- After every execution cycle, the EVM updates and preserves its internal state. An iterator function increases the program counter (PC), decreases gas, controls the stack, and retrieves instructions.
Also Read About Types Of Nodes In Blockchain: Full, Light, Mining And More
Storage within the EVM
- The EVM has access to many contract storage formats.
- Memory: Used when executing a function, this volatile storage is purged after use. Gas-limited but unrestricted.
- Storage: A key-value store that is assigned to accounts and is permanently stored on the blockchain, accessible only by the smart contract associated with that account. similar to storage on a hard drive.
- Stack: A temporary storage area where the EVM executes bytecode by pushing and popping data to carry out calculations.
Instances and Testing Environments
- The Ethereum blockchain’s standard virtual machine is called the EVM.
- Other virtual machines (VMs), like the Chain Virtual Machine (CVM) utilised in “Chain Core,” are available on many blockchain systems.
- Simulated environments that resemble a blockchain virtual machine (VM) are used for development and testing.
Examples include
- The JavaScript Virtual Machine (JVM) is a platform that allows browser-based integrated development environments (IDEs) such as Remix to replicate a blockchain for testing, deployment, and debugging without the need for additional tools.
- Often regarded as a web3 provider, Ganache is an application that offers a local test blockchain environment on a computer and is also used for smart contract testing.
- The simulated environment of the Remix IDE.
In conclusion, the virtual machine (VM), especially the EVM, is an essential feature of blockchain systems that facilitate smart contracts. It enables a variety of decentralised applications by offering the safe, segregated, and deterministic environment required to run complicated code.