Abstract: In view of the existing defects of RFID authentication protocol, based on the Hash function, and the low efficiency of the security protocol authentication in the application of the Internet of Things,  it proposed an improved RFID security mutual authentication protocol, based on the Hash function. This protocol can protect data privacy, and prevent replay attack, privacy track, and spoofing attack. Compared with other protocols of this kind in security and performance, this protocol, which uses Label certification mark Tuse, Tstore and dynamic secret value S, can prevent desynchronization attack, has higher efficiency, and is suitable for low-cost RFID systems.

Key words: Internet of Things, Hash function, radio frequency , identification（RFID）, security authentication, protocol security