Private Messaging

In DPSN, private messaging involves a two-step process:

1. Key Exchange: The publisher initially sends an encrypted key to the subscriber.

2. Message Encryption: Subsequent messages are encrypted using this shared key.

Integrating with the DPSN SDK

Publisher Side

1. Create a Private Message Channel: While creating a new stream, set Visibility = Private Stream. Before starting, register on DPSN Dashboard to start registration as publisher and obtain your publisher access token (Auto-generated on registration) by clicking the top-right menu → Access Tokens to view your publisher access token.

2. Encrypt and Send Messages: Share the private topic ID with the intended recipient

JavaScript

const DPSN = require('dpsn-sdk');

// Create a publisher instance and publish keys
const publisherPrivateChannel = new DPSN.Publisher(process.env.DPSN_DELEGATED_ADDRESS_PVTKEY, 'your_topic');
// Publish key
await publisherPrivateChannel.createPrivateChannel();
// Publish a message
publisherPrivateChannel.publishPrivateMessage(message);

Subscriber Side

1. Subscribe to the Topic: Subscribe to the topic where the public key was published.

2. Receive and Store Public Key: The SDK will automatically handle receiving and storing the public key.

3. Decrypt Messages: Use the decryptPrivateMessage function to decrypt incoming messages on the topic.

JavaScript

const DPSN = require('dpsn-sdk');

// Create a subscriber instance
const subscriber = new DPSN.Subscriber(process.env.DPSN_DELEGATED_ADDRESS_PVTKEY, 'your_topic');

// Subscribe to the topic
subscriber.subscribeToTopic('your_topic', (message) => {
  // Decrypt the message. The first key message will return null
  const decryptedMessage = subscriber.decryptPrivateMessage(message);
  if(decryptedMessage) process(decryptedMessage);
});

Key Features and Benefits

• Simplified Integration: The SDK handles key generation, encryption, and decryption, making it easy to implement private messaging.

• Security: DPSN ensures the security of private messages through robust encryption and key management.

• Scalability: The system can handle a large number of private messages and subscribers.

• Flexibility: Publishers can create multiple private channels and control access to them.