Wireless networks are playing an imperative role in users daily existence; in current scenario, the users want wireless connectivity for all location with all types of service. One of the major challenges for wireless network is security issue. First and foremost task is to detect the security attacks in the network and the second task is to prevent from an authorized attacks. In the authors' view, a lot of researches are going on and somehow they have succeeded in the first case but the second task is very tough due to wireless channel. Their research is based on how to avoid network attack i.e. misbehavior node attack in the WiMAX system.