Archethic Blockchain is using a new consensus called
ARCH (Atomic Rotating Commitment Heuristic) for an uncompromising consensus to support high scalability and high throughput.
Archethic Blockchain is based on three properties:
- Security: Each transaction is validated atomically
- Data consistency: Algorithms ensure to access the latest write and maximum availability
- Fault tolerance: Allow nodes to operate independently even in case of disaster
ARCH consensus is defined by three concepts:
Atomic Commitment: The most absolute form a consensus which implies 100% of concordant responses for the acceptance or refusal of the transaction validation
Heuristic: Set of algorithms which manages the entire network, allowing to elect in a decentralized and coordinated way the nodes in charge to validate or store the transaction chains
Rotating: Node election is constantly changing. No nodes can predict which nodes will validate the transaction before its arrives.
Archethic Blockchain is based on
Hypergeometric distribution laws which from an unpredictable election and formal consensus make it possible to obtain with certainty (99.99999999%) the same answer by querying 197 nodes as would be obtained by querying 100 000 nodes.
Therefore, it makes possible the consensus establishment with a small part of nodes and can resist to attacks of 90% of malicious nodes.
The risk of related availability is ensured by a strict management of the disruptive nodes, which are banished after investigation of the origin of the disagreement.
By supporting more 90% of malicious nodes into its network,
ARCH consensus is above aeronautical or nuclear standard, thanks to the
Atomic Commitment which request the total agreement of the validation nodes and from a
Malicious Detection algorithm to detect the malicious nodes.
Each rotating election is unpredictable, but still verifiable and reproducible. The rotating algorithm sort a list of nodes based on:
Hash of transaction: Unpredictable until the transaction arrives
Daily nonce: Secret shared between the authorized nodes and renewed daily
Node public key: Last node public key
The rotating election produces a proof, named:
Proof of Election which can be verified by any other nodes to ensure the right election of nodes.
From this algorithm, we get a list of nodes which can be filtered according to the constraints of the validation of the transaction.
- P2P availability
- Geographical distribution
When a transaction is willing to be validated, its follows the given workflow:
- The transaction is received by any node (aka
Welcome Nodedetermines the validation nodes from the
Rotating Electionalgorithm and forward the transaction
- The validation nodes after receiving the transaction start some preliminary job to gather the context of the transaction:
- Previous transaction
- List of unspent outputs
- After the context building, the
Cross Validation Nodescommunicate to the
Coordinator Nodethe list of storage nodes involved to gather this information.
Coordinator Nodecan build the
Validation Stampand compute the replication tree. Then it transmits them to the
Cross Validation Nodes.
Cross Validation Nodesverify the content of the
Validation Stamp, sign with or without inconsistencies, and send the
Cross Validation Stampto all the validation nodes involved.
- Once all the
Cross Validation Stampsare received and if the
Atomic Commitmentis reached, the replication phase starts.
- Validation nodes send the transaction to the respective storage nodes:
- Storage nodes responsible for the new transaction chain
- Storage nodes responsible for the outputs of the transactions (transaction's movements addresses, recipients)
- Storage nodes responsible for the Beacon Chain
- The storage for the new transaction chain will notify the validation nodes and the
Welcome Nodeabout the replication, and the
Welcome Nodewill notify the client about it.