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Consensus

Proof of Quorum Optimistic (PoQo)

Liberdus utilizes Proof of Quorum Optimistic (PoQo), an advanced consensus protocol specifically designed for sharded networks with large execution shard sizes. Execution shards are a group of nodes responsible for processing and validating transactions for a specific portion of the network.

PoQo has evolved from earlier PoQ variants to address previous inefficiencies by optimizing how nodes reach consensus, while maintaining decentralization and scalability. Unlike traditional quorum-based systems that rely on extensive message exchanges or gossip, PoQo minimizes communication overhead by introducing a collector node model.

A collector node is an existing active node selected from within the execution shard. Nodes in the execution shard submit their votes to a deterministically selected collector node, which aggregates the votes into a transaction receipt and distributes it back to the shard. This streamlined approach reduces the protocol's complexity from quadratic to linear, enabling Liberdus to maintain high throughput even as the network scales.

There are a multitude of benefits for Liberdus using PoQo. By leveraging deterministic selection and sequential fallback mechanisms for collector nodes, PoQo ensures that consensus is reached efficiently, even in the event of node failures or delays. This design is resilient against malicious behavior, as nodes failing to perform can be penalized, and evidence of misbehavior can lead to swift corrective actions. Furthermore, the use of a supermajority threshold guarantees robustness while enabling the network to handle real-time, high-volume transactions effectively.

PoQo’s innovation lies in balancing efficiency, security, and decentralization, making it an ideal fit for Liberdus’s dynamic and scalable architecture.

Summary of PoQo Advantages

FeatureDescription
Consensus TypeProof of Quorum Optimistic (PoQo)
Optimized ForSharded networks with large execution shards
Consensus ComplexityReduced from O(n²) to O(n) via collector model
Collector NodeSelected deterministically from active nodes within each shard
Fault ToleranceSequential fallback ensures continued operation during node failure
Security MechanismsNode penalties and evidence-based corrective actions
ThroughputScales linearly with network size
ThresholdSupermajority (2/3+) required for consensus
Core StrengthsEfficiency • Scalability • Decentralization

Important

  • Collector-based voting minimizes redundant communication and boosts consensus speed.
  • Sequential fallback guarantees liveness- if one collector fails, another takes over.
  • Penalization system ensures validators remain honest and performant.
  • Supermajority rule maintains Byzantine fault tolerance across shards.
  • PoQo enables Liberdus to scale horizontally without central bottlenecks, aligning with its mission of censorship-resistant global communication.