Cryptographic Assumptions and Implementation Risks

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The ZKP ecosystem's security relies on well-established cryptographic primitives, each carefully selected for security-performance balance within Substrate's runtime framework.

zk-SNARKs

Employing the BLS12-381 elliptic curve for strong 128-bit security and efficient zero-knowledge proofs.

The system employs the BLS12-381 elliptic curve, providing approximately 128-bit security against discrete logarithm attacks.

While this curve offers strong security guarantees, it requires a trusted setup ceremony to generate the Common Reference String (CRS).

To mitigate this single point of failure, the ecosystem implements a multi-party computation (MPC) ceremony with a minimum of 20 participants, where security is preserved as long as at least one participant is honest, coordinated through Substrate's governance mechanisms.

zk-STARKs

Eliminating trusted setups with SHA-3-based proofs designed for long-term quantum-safe security.

Security here derives from the collision resistance of the SHA-3 hash function, providing 256-bit security and quantum resistance.

While zk-STARKs eliminate the trusted setup requirement, they introduce computational overhead that limits their application to specific use cases where transparency is prioritized over performance, typically processed through Substrate's off-chain workers.

Proof-of-Space (PoSp)

Leveraging Poseidon hashing to ensure tamper-proof, efficient verification for decentralized storage.

The integrity of storage proofs depends on the Poseidon hash function's security properties.

The implementation uses specific security parameters (α = 8, rounds = 57) to achieve 128-bit security with optimized circuit complexity, crucial for efficient verification through custom storage verification pallets.

These choices—BLS12-381, SHA-3, and Poseidon—reflect a deliberate alignment with established cryptographic standards, ensuring both theoretical soundness and practical applicability within Substrate's secure runtime environment.