Cryptographic Attestation & Verification Model (CAVM)

VoxaCP introduces a cryptographic attestation framework designed to verify the provenance, integrity, and authenticity of outputs generated by decentralized AI agents. This model uses digital signatures, zero-knowledge proofs, and deterministic state representations to achieve full verifiability — without relying on centralized authorities.

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1. Formal Representation of Model State

Let a VoxaCP Agent be defined as a deterministic function:

f_θ : X → Y

where X is the input space, Y is the output space, and θ ∈ Rⁿ represents the fixed model parameters.

To cryptographically bind an output to a specific model instance, we derive a state commitment using a collision-resistant hash function H:

C = H(f_θ ∥ θ ∥ m)

where m is the message or input prompt, and ∥ denotes byte-level concatenation.

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2. Attestation Signature Scheme

Each agent instance is initialized with a public-private key pair (pk, sk). Upon generating an output y = f_θ(m), the agent signs the tuple (m, y, C) using a digital signature algorithm such as EdDSA:

σ = Sign_sk(m, y, C)

The tuple (m, y, C, σ, pk) forms the attestation package, which can be independently verified:

Verify_pk(m, y, C, σ) = true

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3. Deterministic Output Verification

To eliminate nondeterminism in generative model outputs, VoxaCP enforces seed-locked generation:

y = f_θ(m; s)

where s is a shared PRNG seed. This guarantees that the same input and seed always yield the same output, satisfying the deterministic constraint:

f_θ(m₁; s) = f_θ(m₂; s) ⇒ m₁ = m₂

The seed is included in the attestation hash:

C = H(f_θ ∥ θ ∥ m ∥ s)

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4. Zero-Knowledge Proof of Execution

For sensitive or proprietary models, VoxaCP supports optional zk-SNARK-compatible attestation. Here, a prover generates a succinct proof π such that:

π = Prove(R_f, m, y)

where R_f encodes the execution circuit of f_θ. A verifier can confirm the correctness of the computation without learning the model internals:

Verify_ZK(π, m, y) = true

This enables third parties to trust the authenticity of model outputs without revealing model parameters or architecture.

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5. Blockchain Anchoring

To guarantee immutability, VoxaCP periodically commits attestation hashes to a blockchain smart contract (e.g., Ethereum):

SubmitAttestation(C, t) → on-chain

where t is a timestamp or block height. This creates a tamper-proof audit trail of model responses that can be queried and verified by any participant.

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6. Security Assumptions

The security of the VoxaCP Cryptographic Attestation & Verification Model is based on well-established cryptographic hardness assumptions:

• Collision resistance of the hash function H

• Unforgeability of the digital signature scheme under chosen-message attacks (UF-CMA)

• Soundness and completeness of the zk-SNARK proof system

• Determinism of the model f_θ under fixed seeds

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