KZG Revocation Analysis

Compares KZG polynomial commitments (O(1) gas) against a Merkle tree baseline (O(depth) gas) for blockchain-based credential revocation, benchmarked on the Hoodi testnet with the EIP-4844 trusted setup.

Results

KZG vs. Merkle

Property	KZG	Merkle
Verify gas	O(1) — 43,026 gas	O(depth) — 27k–32k gas
Update gas	O(1) — 39,997 gas	O(1) — 30,075 gas
Commitment size	48 bytes (G1 point)	32 bytes (keccak256)
Proof size	160 bytes (constant)	32 × depth bytes
Security bound	≤ 4,095 credentials/poly	Unlimited
Off-chain verify	0.59 ms (C backend)	Sub-ms

KZG gas is constant because the commitment is always a 48-byte G1 point and the verification payload always 160 bytes, independent of polynomial degree. Merkle verification adds ~906 gas per depth level (one keccak256 per proof element).

Merkle Batch Efficiency (Hoodi testnet)

Batch size	Gas per revocation	Saving
1	30,074	—
10	3,008	90%
50	602	98%
100	301	99%

Structure

contracts/   KZGRevocation.sol, KZGVerifier.sol, MerkleRevocation.sol
scripts/     benchmarkUpdateCommitmentGas.js, benchmarkBaseline.js, compareResults.js
results/     gas_sweep_update_commitment.json, baseline_merkle.json, hoodi_kzg_test_results.json
src/         C implementation (c-kzg-4844)
bindings/    Python bindings
test/        MerkleRevocation.test.js

Running the Benchmarks

npm install

# KZG gas sweep — no external node needed
npx hardhat run scripts/benchmarkUpdateCommitmentGas.js --network hardhat

# Merkle baseline — requires Hoodi RPC in hardhat.config.js
npx hardhat run scripts/benchmarkBaseline.js --network hoodi

# C backend timing
cd src && make benchmark_kzg_timing && ./benchmark_kzg_timing

# Merkle contract tests
npx hardhat test test/MerkleRevocation.test.js

Security Note

KZG security requires degree ≤ 4,095 (EIP-4844 trusted setup bound). Gas costs are identical beyond this limit but cryptographic guarantees are not. Scale horizontally with multiple polynomials rather than increasing degree.

License

Apache-2.0

Citation

@misc{kzg_revocation_analysis_2026,
  title        = {KZG Polynomial Commitment for Shared SSI Revocation},
  author       = {Kosubiene, Gintare and Masteika, Saulius},
  year         = {2026},
  howpublished = {GitHub Repository}
}