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Atul Khekade
Atul Khekade

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[Informative] ISO20022 Payments Application Generator via AI for XDC Network

For managing large value payments efficiently while incorporating elements of ISO 20022 message types and ensuring no double spend through tokenization, without the full complexity of a blockchain, a simplified but effective data structure can be designed. This design will focus on the core requirements: representing payment information according to the ISO 20022 standards and ensuring the uniqueness and non-replicability of each payment through tokenization.

Data Structure Design

The data structure combines elements of traditional databases for managing structured data with cryptographic techniques for tokenization. This ensures each payment is unique, traceable, and cannot be double-spent without the overhead of a full blockchain infrastructure.

1. Payment Information Structure

This structure stores the payment information in a format that is compliant with the ISO 20022 standards, focusing on key attributes relevant to large value transactions.


class PaymentInfo:
    def __init__(self, payment_id, debtor, creditor, amount, currency, payment_date, token):
        self.payment_id = payment_id  # Unique identifier for the payment
        self.debtor = debtor  # Debtor information (account, name, address)
        self.creditor = creditor  # Creditor information (account, name, address)
        self.amount = amount  # Amount of the payment
        self.currency = currency  # Currency of the payment
        self.payment_date = payment_date  # Date of the payment
        self.token = token  # Unique token representing this payment transaction
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2. Tokenization Mechanism

To prevent double spending, each payment transfer is tokenized. This token is a cryptographic hash that uniquely represents each payment based on its details. The hash function ensures that even minor differences in payment details result in a completely different token, thus ensuring the uniqueness of each transaction.


import hashlib

def generate_payment_token(payment_info):
    # Create a unique string representation of the payment information
    payment_string = f"{payment_info.payment_id}|{payment_info.debtor}|{payment_info.creditor}|{payment_info.amount}|{payment_info.currency}|{payment_info.payment_date}"

    # Use a cryptographic hash function to generate a unique token
    token = hashlib.sha256(payment_string.encode()).hexdigest()
    return token
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3. Payment Management System

This system manages the lifecycle of each payment, including creation, token generation, and ensuring no double spending.


class PaymentManagementSystem:
    def __init__(self):
        self.payments = {}  # Stores payment_id: PaymentInfo

    def create_payment(self, payment_id, debtor, creditor, amount, currency, payment_date):
        # Generate a unique token for the new payment
        temp_payment_info = PaymentInfo(payment_id, debtor, creditor, amount, currency, payment_date, None)
        token = generate_payment_token(temp_payment_info)

        # Ensure the token is unique to prevent double spending
        if token not in self.payments:
            # Add token to the payment info
            temp_payment_info.token = token
            # Store the payment information
            self.payments[payment_id] = temp_payment_info
            return True
            # Token already exists, indicating a potential double spend attempt
            return False
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Using XDC Network for Payment Block Confirmations

To integrate the payment information structure and its management system with the XDC Network, where a block of payments can be verified and confirmed, we need to design an approach that leverages the unique features of the XDC Network, especially its Delegated Proof of Stake (XDPoS 2.0) consensus mechanism, the HotStuff protocol for consensus, and its forensic monitoring capabilities for security.

This design would involve creating a smart contract on the XDC Network that interacts with the payment management system to ensure each block of payments is unique, confirmed, and immutable. The smart contract will serve as the bridge between the external system and the blockchain, providing a decentralized verification mechanism for the payments.

Step 1: Smart Contract for Payment Verification

The smart contract will be responsible for verifying each block of payments by checking the unique token associated with each payment. This ensures no double spending and maintains the integrity of the payment system.


pragma solidity ^0.8.0;

contract PaymentVerification {
    struct Payment {
        string paymentId;
        bytes32 token; // Unique token generated off-chain
        bool verified;

    mapping(bytes32 => Payment) public payments;

    event PaymentAdded(string paymentId, bytes32 token);
    event PaymentVerified(string paymentId, bytes32 token);

    // Add a new payment to the blockchain for verification
    function addPayment(string memory paymentId, bytes32 token) public {
        require(payments[token].token == 0, "Payment already exists.");
        payments[token] = Payment(paymentId, token, false);
        emit PaymentAdded(paymentId, token);

    // Verify a payment on the blockchain
    function verifyPayment(string memory paymentId, bytes32 token) public {
        require(payments[token].token != 0, "Payment does not exist.");
        require(!payments[token].verified, "Payment already verified.");
        payments[token].verified = true;
        emit PaymentVerified(paymentId, token);
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Step 2: Interfacing the Payment Management System with XDC Network

To interface the external payment management system with the XDC Network, you can use the XDC Network's SDKs or APIs. This involves sending the payment details from the external system to the smart contract on the XDC Network for verification.

Example Python Script for Interfacing with the Smart Contract

Assuming you have a Python-based backend for the payment management system, you can use the library to interact with the smart contract.


from web3 import Web3

# Connect to the XDC Network
w3 = Web3(Web3.HTTPProvider(''))

# Assume this is the address of the deployed PaymentVerification smart contract
contract_address = '0xYourContractAddress'
contract_abi = # ABI of the PaymentVerification contract

# Load the contract
contract = w3.eth.contract(address=contract_address, abi=contract_abi)

# Function to add a payment to the blockchain
def add_payment_to_blockchain(payment_id, token):
    # Assume you have the function to sign and send the transaction
    tx_hash = contract.functions.addPayment(payment_id, token).transact()
    receipt = w3.eth.waitForTransactionReceipt(tx_hash)
    return receipt

# Example usage
payment_id = 'PAY123'
token = '0xUniqueTokenGeneratedForThePayment'
receipt = add_payment_to_blockchain(payment_id, token)
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This approach provides a method to integrate a payment management system with the XDC Network, leveraging smart contracts for decentralized verification and ensuring the integrity and uniqueness of each payment. The external system is responsible for generating unique tokens for each payment, which are then verified on the blockchain, providing an immutable record of transactions.

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