Healthcare Blockchain System, Privacy Preserving Solution

This document details a healthcare system leveraging Zero-Knowledge Proofs (ZKPs) to securely verify blood pressure readings while maintaining patient privacy.

Key Features

• Role-Based Access Control: Strict access control for Administrators, Doctors, and Insurance Providers.
• Secure Blood Pressure Verification: ZKP implementation ensures only the validity of blood pressure readings (within a specified range) is revealed, not the actual values.
• Privacy-Preserving Claims System: Insurance claims are processed while protecting sensitive patient data.
• Intuitive Dashboards: Dedicated dashboards for Admins (user management), Doctors (patient registration and claim submission), and Insurance Providers (claim verification).

System Requirements

• Node.js: v14 or higher
• MongoDB: v4.4 or higher
• Ganache: Local blockchain emulator (for development)
• MetaMask: Browser extension for interacting with Ganache.
• Git: Version control system.
• Circom: For compiling ZKP circuits.

Installation and Setup

1. Clone and Install Dependencies:

   git clone <repository_url>
   cd <project_directory>
   npm install
   cd backend && npm install
   cd ../frontend && npm install
   npm install -g circom

2. ZKP Circuit Setup:

   cd circuits
   circom bloodPressureRange.circom --r1cs --wasm --sym

3. Backend Setup:

   cd backend
   node scripts/setup-complete.js  // Compiles circuit, generates keys, sets up the ZKP system
   node scripts/setup-roles.js    // Deploys contracts;  **Note the contract address displayed.**

4. Environment Configuration: Update the .env file with the contract address obtained from step 3. Also note the account addresses and their assigned roles.

5. Ganache Setup:

   • Download and install Ganache.
   • Create a new workspace.
   • Keep Ganache running throughout the process.

6. MetaMask Configuration:

   • Add the Ganache network to MetaMask:
     • Network Name: Ganache
     • RPC URL: http://127.0.0.1:7545
     • Chain ID: 1337
     • Currency: ETH
   • Import accounts from Ganache in the following order:
     1. Admin
     2. Doctor
     3. Insurance Provider

7. Start the Application:

   • Start MongoDB.
   • In the backend directory: node server.js
   • In the root directory: npm start (to start the frontend)

Account Roles and Permissions

Account #	Role	Permissions
1	Admin	User management
2	Doctor	Patient registration, claim submission
3	Insurance Provider	Claim verification

Important: Maintain the order of accounts from Ganache (Admin, Doctor, Insurance Provider).

Testing the System

1. ZKP Test: cd backend && node scripts/test-zkp.js

2. Doctor Workflow:

   • Log in as the Doctor (Account #2).
   • Submit claims with varying blood pressure values (e.g., 130, 150). Observe eligibility based on the defined range.

3. Insurance Provider Workflow:

   • Log in as the Insurance Provider (Account #3).
   • Review submitted claims.
   • Verify proofs using the "Verify Proof" button. Note that the actual blood pressure values remain hidden.

Troubleshooting

• MetaMask Connection: Ensure Ganache is running, network settings in MetaMask are correct, and the appropriate account is selected.
• MongoDB Connection: Verify MongoDB is running, the connection string in .env is accurate, and database permissions are correctly configured.
• ZKP Verification: Re-run setup-complete.js, check circuit compilation logs, and review proof generation parameters.

Security Considerations

• Zero-Knowledge Proofs: Fundamental for data privacy.
• Role-Based Access Control: Limits access based on roles.
• JWT Authentication: Secure authentication mechanism.
• Encrypted Data Storage: Protects data at rest.
• (Future) Two-Factor Authentication: Enhanced