(The recent ARP virus tyranny has disturbed almost all the local area networks. Wherever it goes, the network fails frequently, the speed of the network suddenly slows down, and the network connection is intermittent, which affects the normal office order at light, and can cause the entire local area network at worst. Paralysis, and even the formation of irreparable loss. Therefore, how to adopt effective methods to prevent ARP virus has become the top priority of the recent network security office.)