Ethereum Cookbook

How to do it…

1. Whisper uses the shh protocol to send messages between DApps. In Web3JS, you can directly access the object from the root:

web3.shh

2. Create a new identity using the shh object. Call the newIdentity function to do this:

var identity = web3.shh.newIdentity();

3. Use the post method to broadcast the messages:

web3.shh.post({    // ...});

4. Every post method accepts a JSON object with the following parameters:

• topic: One or multiple arbitrary data items that are used to encode the abstract topic of this message. It can be used to filter messages based on requirements.
• payload: Unformatted byte array that provides the data to be sent. Similar to topic. 
• TTL: Time for the message to live on the network in seconds. This defaults to ...