node 搭设的事件发射器，出现了问题，代码如下，我认为是这一部份的问题请大神看看

var events = require('events');
var net = require('net');
var channel = new events.EventEmitter();
channel.clients = {};
channel.subscriptions = {};
 
channel.on('join',function(id,client){   //on 方法本身就有遍历的功能
this.clients[id] = client;
**this.subscriptions[id] = function(senderId,message){
     if(id != senderId){           //除了自己以外的都发送
         this.clients[id].write(message);
      }**
//我认为是这里的问题！！
} 
this.on('broadcast',this.subscriptions[id]);
var welcome = 'welcome!\n' + this.listeners('broadcast').length;
client.write(welcome);
});

 var sever = net.createServer(function(client){
     var id = client.remoteAddress + ':' + client.remorePort;

 channel.emit('join',id,client);
 client.on('data',function(data){
     data = data.toString();
     channel.emit('broadcast',id,data);
 });
 console.log('connect!');

 });
 sever.listen(8888);
 
 

请大神看看
当我运行两个cmd 时并不能接收对方发出的消息。