Tier 3

Tier 3 verification concept. Trusted oracles corroborate submitted data, and the result is recorded on chain.

Tier 3 verification adds a layer of validation through oracles. Use it for data that needs external corroboration, or that comes from indirect sources. The snippets below are conceptual: they show the shape of the flow, not a shipped SDK API. Adapt them to the oracle service you use.

Oracle-backed verification process

1. Oracle Selection: A trusted oracle is chosen to serve as an intermediary for data verification.
2. Data Submission & Request: Data is submitted to the blockchain, and a request is made to the oracle for verification.
3. Oracle Verification: The oracle verifies the data’s authenticity against external sources or predefined criteria.
4. Verification Result: The oracle provides a verification result, which is then recorded on the blockchain.

Prerequisites

• Integration with a trusted oracle service that can provide external data verification.
• Smart contracts or blockchain protocols capable of handling oracle responses.

1. Oracle selection

Identify and integrate a trusted oracle service into the blockchain system for external data verification.

// import necessary libraries and functions
import { OracleService } from './oracleService.js';

const selectOracle = async () => {
  // Select a trusted oracle from a list of available services
  const oracle = new OracleService('trusted_oracle_url');
  return oracle;
};

export const trustedOracle = await selectOracle();

2. Data submission and request

Data is submitted to the blockchain, and a verification request is sent to the chosen oracle.

// import necessary libraries and functions
import { trustedOracle } from './selectOracle.js';
import { submitToBlockchain } from './utils.js';

const submitDataAndRequestVerification = async (data) => {
  // Data submission to the blockchain
  const submissionPackage = preprocessData(data);
  submitToBlockchain(submissionPackage);

  // Send a verification request to the oracle
  trustedOracle.requestVerification(data);
};

submitDataAndRequestVerification(externalData);

3. Oracle verification

The oracle conducts verification by comparing the submitted data against reliable external sources or predefined criteria.

// Assuming the oracle service provides a method to validate data
import { trustedOracle } from './selectOracle.js';

const verifyDataWithOracle = async (data) => {
  const verificationResult = await trustedOracle.verify(data);
  return verificationResult;
};

4. Verification result

The oracle’s verification result is received and recorded on the blockchain, completing the Tier 3 verification process.

// import necessary libraries and functions
import { updateDataStatusWithOracle } from './utils.js';

const recordVerificationResult = async (dataId, oracleResult) => {
  // Record the oracle's verification result on the blockchain
  updateDataStatusWithOracle(dataId, oracleResult);
};

// Example usage
recordVerificationResult(submittedDataId, oracleVerificationOutcome);

Things to watch

• Set strict criteria for choosing oracles, so the result is reliable and independent.
• Monitor oracle performance over time.
• Consider requiring agreement between several oracles before recording a result.