摘要:RFID has been more and more attention and application by people, but the existence of security and privacy problems worthy of attention is concern. The certification process analysis of several typical security protocols is based on existing RFID authentication protocol. It proposed an improved bidirectional authentication algorithm. The use of one-way HASH function can solve the security problem of RFID. The protocol has anti-replay, impedance analysis, forgery, and tracking performance, and is suitable for the distributed system. With the development of computer and Internet is widely used in various industries, interaction of high-speed information transfer process. The problem of information security is concern. The paper produce and use all kinds of algorithms based on hash function firstly. Then as information on a solid safety lock, MD5, SHA-1 file verification, encryption, digital signature, PKI building has security full of all kinds of information. Finally, it can effectively prevent the attack, ensuring the authenticity of the information not to be modified or leaks