After your English is getting better, you will like North America. Don't go back to China, that's not your destiny. Trust me, stay here and you will be great in a couple of years after the recession. The reason is that you are the exactly professional most companies needs. Not like most of guys with Cisco or Nortel certified, you have the real knowledge on routing algorithm and definitely much better than those CCIE etc.. Although most companies cut research budget now, it's will be okey in future. So don't worry too much, try to improve your oral English and pay more attention on R&D group of big name companies. Good luck.