code: protected void processGossipHello(Tree data) {
  
  		// Debug
  		String sender = data.get("sender", (String) null);
  		if (debugHeartbeats) {
  			logger.info("Gossip \"hello\" received from \"" + sender + "\" node:\r\n" + data);
  		}
  
  		// Get previous parameters
  		String host = data.get("host", (String) null);
  		int port = data.get("port", 0);
  
  		// Register as offline node (if unknown)
  		registerAsNewNode(sender, host, port);
  	}
docs: --- GOSSIP HELLO MESSAGE RECEIVED ---