Simple event subscription pattern in NodeJS

events_subscription.js

var events = require('events'),
	net = require('net'),
	channel = new events.EventEmitter();
	
channel.clients = {};
channel.subscriptions = {};

// Add listener on join event
// we save client user object and send
channel.on('join', function(id, client) {
	this.clients[id] = client;
	this.subscriptions[id] = function(senderId, message) {
		// ignore from user himself
		if (id != senderId)
		{
			this.clients[id].write(message);
		}
	}
	this.on('broadcast', this.subscriptions[id]);
});

var server = net.createServer(function(client){
	var id = client.remoteAddress + ':' + client.remotePort;
	client.on('connect', function(){
		// Emit join event after user connect
		channel.emit('join', id, client);
	});
	client.on('data', function(data) {
		data = data.toString();
		// Emit broadcast event for channel,
		// when user sends a message
		channel.emit('broadcast', id, data);
	});
});

server.listen(8888);