Blockchain-based Circuit Allocation System

Official repository of the undergraduate thesis of Gessica F. Mendonça Azevedo.

API for decentralized circuit request management that extends the MEICAN (Management Environment of Inter-domain Circuits for Advanced Networks) project with:

• Smart Contract MEICANRequestManager.sol (Solidity 0.8.20) – records IPFS requests, decisions, and links.
• Node/Express Backend (backend/requestManager.js) – integrates with the contract (ethers.js 6.13), uploads files to IPFS via Pinata, and exposes REST/WebSockets routes.
• HTML + JS Frontend – lists requests, performs hybrid encryption (AES-CBC 256 + RSA 2048) in the browser, and triggers the backend/contract.
• Test scripts to measure gas and execution time.

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Overview

Objective	Description
Auditability	Record approvals/rejections of circuits (and respective policy files) in an immutable way.
Transparency	Allow any interested party to validate the integrity of the process by querying events on the blockchain.
Data protection	Policy files never travel in plain text: they are encrypted locally, uploaded to Pinata, and only their hashes and links are made public.

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Repository structure

meican-smart-contract-api-main/
  ├── ABI/ # Post-compile generated ABIs
  ├── backend/ # API Express + Pinata/Ethereum integration
  │ └── .env # Environment variables file
  ├── contracts/ # Smart contracts Solidity
  ├── migrations/ # Scripts Truffle
  ├── php/ # LEGACY (not required, kept for reference)
  ├── scripts/ # Deployment, utilities and performance testing
  ├── test/ # Test scripts
  ├── web/ # Static front-end
  └── README.md # This file

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Requirements

Tool	Minimum version	Observation
Node.js	20 LTS
npm	10
Truffle	5.11	npm i -g truffle
Ganache CLI	7.x	local blockchain
Solidity	0.8.20	compiler via Truffle
Git	—
Pinata	Free account	generate API Keys

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Main dependencies

• ethers.js 6.13.7 – Ethereum interaction
• @pinata/sdk 2.1 – upload & pinning IPFS
• jszip 3.10 – ZIP packaging
• node-forge / Web Crypto API – RSA/AES in the browser
• Truffle 5 / Ganache – local development

Settings

1. Clone the repository

   git clone https://github.com/gmazevedo/meican-smart-contract-api.git
   cd meican-smart-contract-api
   

2. Install the dependencies

    npm install
   

3. Create the environment variables file

   Path: backend/.env

    RPC_URL=http://127.0.0.1:8545  # Ganache endpoint
    REQUEST_MANAGER_CONTRACT_ADDRESS= # Contract address
    ADMIN_ADDRESS=         # Deploy account
    PRIVATE_KEY=          # Deploy account private key
    PORT=8000
    PINATA_API_KEY=       # Pinata API key
    PINATA_SECRET_API_KEY=  # Pinata API key secret

4. Initialize local blockchain (Ethereum Mainnet Similar)

    ganache --chain.chainId 1 --chain.networkId 1 --miner.blockGasLimit 30000000 --miner.defaultGasPrice 430000000

5. Compile and migrate contracts

    truffle compile --config truffle-config.cjs
    truffle migrate --reset --network development --config truffle-config.cjs

6. ABI update

    cp build/contracts/MEICANRequestManager.json ABI/MEICANRequestManagerABI.json

7. Start the backend

    cd backend
    node requestManager.js

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Endpoints & main pages

Page	Route	Function
http://localhost:8000/circuitRequest.html	/circuitRequest.html	User opens a new request
http://localhost:8000/userRequestViewer.html	/userRequestViewer.html	User tracks their requests
http://localhost:8000/pendingRequests.html	/pendingRequests.html	Operator lists pending requests
http://localhost:8000/requestEval.html	/requestEval.html	Operator approves/rejects + uploads policy

Util pages

Page	Route	Function
http://localhost:8000/uploadPolicy.html	/uploadPolicy.html	Standalone IPFS upload tool
http://localhost:8000/decrypt.html	/decrypt.html	Local decryption via private key

License

Distributed under the MIT License.

© 2025 Gessica Franciéle Mendonça Azevedo