Quorum project goals
Create a permissioned version of Ethereum that supports:
- Governance – nodes & activity are tied to real world identities.
- Confidentiality – details of transactions are private (private chain).
- Security – no trust is assumed between participants / nodes.
The architecture of Quorum
- Transaction Manager – Allow access to encrypted transaction data for private transactions, manages local data store and communication with other Transaction Managers.
- Crypto Enclave – responsible for private key management and encryption and decryption of private transaction data.
- QuorumChain – The Quorum Core. Enforced by configurable consensus (voting based).
- Network Manager – controls access to the network, enabling a permissioned network to be created.
Quorom is built off Go Ethereum, the base code for Ethereum blockchain but with four major distinctions:
- Peer permissions management (Premissioned)
- Configurable Consensus
- Higher performance
Quorum Mechanisms (cont…)
- Quorum is designed to be permissioned, meaning that networks using Quorum won’t open to all.
- Quorum’s permissioned chain is a consortium blockchain, this means that it is implemented between participants that are pre-approved by a designated authority.
- A consortium blockchain runs with the same features and protocols of a normal blockchain, but maintains the failsafe of only relying on permitted nodes.
- Integrated with Comae’s Porosity, the first decompiler for the Ethereum Virtual Machine.
- Quorom proposed private chain (transactions are verified by details are not exposed).
- Private transactions are sent directly between specified recipients by Quorum’s privacy engine, called Constellation.
- Hash of private transactions is still included in the shared blockchain.
- Private smart contract state is known to and validated by only parties to the contract and approved third parties, like regulators.
- The Zero-knowledge Security Layer (ZSL) allows for cryptographically assured, private settlement of digitized assets on Quorom.
Consensus (Raft Consensus)
- Quorum’s consensus protocol is called QuorumChain and is initiated within the genesis block.
- A certain set ofnodes are relegated voting rights and all with voting rights and confer voting rights to others.
- A smart contract is used within the genesis block to assign voting rights and tracks the status of all voting nodes within the network as it updates.
- The smart contract also specify a block makers so that all the coming blocks are made by them.
- Quorum chain cannot be forked thus ensure settlement finalty.
- Faster than traditional blockchain (~25 milliseconds blocktime).
- Simplistic consensus mechanism.
- Straightforward voting procedure called by a smart contract.
- Small number of nodes is significantly fast than proof-of-work or proof-of-stake.
Quorum and ZSL
- Quorum implemented underneath of Zero Knowledge Security Layer (ZSL) to provide a secure layer (very similar to HTTP and SSL).
- ZSL enables transfer of digital assets on a distributed ledger without revealing any information about the sender, recipient, or quantity of assets.
- ZSL uses zk-SNARKs (Zero-knowledge cryptographic proofs).
- ZSL was encapsulated as a smart contract in the Quorum chain.
Quorum Use Cases
- Assume Alice want to buy some CAT shares with USD from Bob:
Quorum Use Cases (cont…)
- Alice create a contract as shown in the diagram above and Bob accept the contract.
- The state of the contract becomes Accepted.
- Alice then pay USD to Bob.
- The state of the contract becomes Paid.
- Bob then release shares to Alice
- The state of the contract becomes Delivered.
- After the share has been delivered, the state of the contract becomes Settled.
- The transaction is made privately thus other participants in that shared chain have no idea about who is trading and what was being traded.
The core innovation of blockchain is digital trust, provable and intrinsic to the system without reliance on an external authority. Open source code can be transparently vetted and validated to ensure it does exactly what is say it does.
Quorum is GPL/LGPL licensed, this ensures that the platform will be free to use in perpetuity and encourages experimentation.
Quorum is able to incorporate the majority of Ethereum updates quickly and seamlessly.