Ethereum Virtual Machine (EVM)
All blockchains are considered to be a form of a distributed ledger also called DLT (distributed ledger technology), which is a consensus of shared, and synchronized duplicated digital data, a database with no central regulator.
This ‘distributed ledger’ analogy applies to characterize the blockchain primitives, which allow a currency to be decentralized using primary cryptography mechanisms. Ethereum’s native cryptocurrency follows the same basic rules. Over and above that, it provides a much more powerful and complex feature - programs that run on the Ethereum blockchain that are called smart contracts, which govern the behavior of accounts within the Ethereum state. Due to this, a need for a more suitable sophisticated analogy appears that is a ‘distributed state machine’.
Ethereum state stores all accounts and balances as well as the state of the machine. This state represents a large data structure that changes from block to block according to a predetermined bunch of principles and can execute arbitrary machine code. The set of particular rules for calculating a new valid state from block to block are controlled by a single ‘canonical’ computer called the Ethereum Virtual Machine (EVM).
A physical EVM instance is supported by thousands of connected computers running the Ethereum client. Every Ethereum node keeps a copy of its state. A state change in the EVM is committed and spread throughout the entire Ethereum network, and any node can broadcast a transaction request for it to perform arbitrary computation. Whenever it happens other participants on the network verify, validate, and execute the computation. The record of all requests along with the present state of EVM is agreed upon by all nodes and stored in the blockchain.
Ethereum virtual machine, or EVM for short, is the universe in which all Ethereum accounts and smart contracts live. It is a Turing-complete virtual machine that enables the execution of code just as intended. Every Ethereum node runs on the EVM to maintain consensus across the network.
Benefits of Humanode’s compatibility with Ethereum
To bring crypto-biometric technology to existing protocols Humanode Network includes an EVM pallet that allows it to run Solidity smart contracts and use existing developer tools. Its implementation is based on SputnikVM which consists of 4 modules: evm, evm-core, evm-runtime, and evm-gasometer.
One of the goals of Humanode network is to solve current issues of the transaction fee pricing by making the fees stable in USD terms despite the volatility of the native token. Hence, evm-gasometer is replaced with a cost-based fee system.
Unified accounts, first proposed by Moonbeam, a Polkadot smart contract platform for building natively interoperable blockchain applications, solve the problem of account incompatibility between H256 Substrate addresses and H160 Ethereum addresses where the user is unable to send transactions directly, has to have two accounts, and move assets between them to get access to both chains. With unified accounts, a single H160 is all the user needs making her experience seamless.
Moving a decentralized application (dApp) or a smart contract framework from Ethereum to Humanode will require minimal changes. Solidity smart contracts, block explorers, development tools, bridges, and frameworks for decentralized autonomous organizations (DAOs) are easily ported to the chain based on equal validators. By bridging Humanode to other EVM-compatible chains, the network will be able to provide private biometric processing and Sybil-resistance to dApps and protocols based on other chains.
A Sybil-proof system was best conceptualized by Ethereum co-founder Vitalik Buterin as a ‘unique identity system’ for generating tokens that prove that identity is not part of a Sybil attack. In recent years, attempts in the field were made by several blockchain-based initiatives. Nevertheless, there were still no relevant Sybil-resistant identity mechanisms. In other words, in the digital space, there was a possibility for users to create multiple accounts in one system using distinct pseudonyms to vote several times or receive multiple rewards, etc. The Humanode project came closest to solving this problem. Humanode combines state-of-art liveness detection, multimodal biometric processing with constant proof-of-existence to create a robust Sybil-resistance that would safeguard the system from spoofs and bypasses committed by bad actors. A big part of Sybil defense is in the hands of human nodes themselves - the more there are human nodes that actively govern and participate in the life of the network, the stronger the resistance as Sybil identities become less eligible to become validator nodes.
Moreover, besides biometrics and blockchain technologies in the broad sense, Humanode utilizes crypto-biometrics which is based on a stack of various disciplines and technologies such as cybersecurity, encryption, liveness detection, and zero-knowledge proofs. Thus, there will be no more data privacy concerns. A biometric smart contract written in Solidity deployed on a needed chain will communicate with, for instance, a decentralized finance (DeFi) protocol, and then send the request to the Humanode network where biometric data is stored. Without revealing the user's identity, the Humanode network sends zero-knowledge liveness proof and identity check back to the DeFi protocol proving the user is the same real human being without using any personally identifiable information (PII).
Thanks to EVM support, Humanode could easily integrate DAOs frameworks, for example, Aragon DAO, and integrate credit-scoring into platforms like Maker, Aave, and Compound. The key point here is that biometrics is unique, especially when combined with crypto-biometrics, which provide the highest level of security and privacy as well as identity verification for credit scores. It is a win-win situation for both the creditor and the debtor, while also resolving a major issue for platforms in terms of establishing trust. What’s more, Humanode biometric identifications are likely to be integrated into Ethereum-based NFT marketplaces and metaverses as a means to prove ownership or origin of NFTs with your biometrics, either as a browser extension or as a full-fledged app, which will offer the most user-friendly interface and the easiest way to interact with blockchain-based services as due to Humanode technology, to enter these platforms and to sign transactions users will only need to scan their faces.
Uniting crypto communities
Compatibility with Ethereum means that any Ethereum developer will not see Humanode as a rival development ecosystem they need to learn, but an alternative they can easily jump into and start building on, and vice versa.
It is worth noting that some major blockchain ecosystems have raised huge amounts of funds but besides these great financial incentives have failed to build large and devoted developer communities. The main reason is that lots of developers have spent years building the Ethereum experience and are usually unwilling to start over with an unknown development environment. While that is going on, projects that aim for greater Ethereum compatibility for developers, such as Binance Smart Chain (BSC), Avalanche’s EVM compatible C-chain or Polygon based on Ethermint, to name a few, developing rapidly and successfully, have flourishing developer communities which complement the Ethereum one. Similarly, one of Humanode's goals is to grow alongside Ethereum and its developer community, rather than compete with them, which will open up many opportunities for both Humanode developers and Ethereum coders.