Cloud Provers

Overview

In the Cubiq Network, Cloud Provers are specialized nodes responsible for the computationally intensive task of generating zero-knowledge proofs (ZKPs). These proofs cryptographically verify the correctness of transactions and state changes on the network, allowing lightweight mobile Qubes to validate the blockchain without needing to re-execute every transaction.

This separation of concerns—computation by provers, verification by Qubes—is fundamental to Cubiq's mobile-native design, enabling broad participation and scalability.

Role of Cloud Provers

Cloud Provers perform several critical functions:

• Proof Generation: They take transaction batches and generate compact zero-knowledge proofs using advanced cryptographic techniques (e.g., Plonky3).
• Execution Trace Generation: They simulate transaction execution within the zkEVM to create the necessary traces for proof generation.
• Proof Aggregation: Provers can aggregate multiple individual proofs into a single, more compact proof, further enhancing scalability.
• zkURL Publication: Once generated, proofs are published via the zkURL protocol for efficient distribution and retrieval by Qubes.

Prover Network Architecture

The Cloud Prover Network is designed for high availability, scalability, and decentralization:

Distributed Infrastructure

• Geographic Distribution: Provers are deployed globally to minimize latency and enhance resilience.
• Horizontal Scaling: The network can scale horizontally by adding more prover instances as demand for proof generation increases.
• Load Balancing: Incoming proof requests are distributed across available provers to optimize throughput.

Technology Stack

• GPU Acceleration: Provers leverage powerful GPUs to accelerate the computationally intensive ZKP generation process.
• Rust-based zkEVM: Used for efficient and provable execution trace generation.
• Containerization: Prover instances are containerized for consistent deployment and management.

Plonky3 Integration

Cubiq Network utilizes Plonky3 as its primary zero-knowledge proof system for Cloud Provers. Plonky3 offers several advantages:

• Recursive Proofs: Enables the aggregation of multiple proofs into a single, compact proof, which is highly efficient for on-chain verification and mobile Qube validation.
• STARK-based: Provides strong cryptographic security guarantees and transparency.
• Fast Proving Times: Optimized for performance, allowing for rapid proof generation.
• Small Proof Sizes: Generates proofs that are small enough to be efficiently transmitted and verified by mobile devices.

// Pseudocode: Simplified Plonky3 proof generation flow
function generate_proof(transactions: List<Transaction>): ZKProof {
  // 1. Execute transactions in zkEVM to get execution trace
  let trace = zk_evm.execute(transactions);

  // 2. Convert trace into Plonky3 circuit constraints
  let circuit = plonky3.build_circuit(trace);

  // 3. Generate the zero-knowledge proof
  let proof = plonky3.prove(circuit);

  return proof;
}

Scalability and Performance

The Cloud Prover Network is designed to meet the demands of a global, mobile-first blockchain:

Throughput

• Parallel Proving: Multiple provers can generate proofs concurrently for different blocks or transaction batches.
• Batching: Transactions are batched to optimize proof generation efficiency.

Latency

• Optimized Algorithms: Continuous research and development to reduce proof generation times.
• Geographic Proximity: Users are routed to the nearest available prover for lower latency.