In recent years, radio frequency identification (RFID) systems have become popular for identification. The key technology to protect the security of RFID systems is mutual authentication between the tags and the server. To enhance the efficiency of RFID systems, recently, Liu et al. proposed a group authentication protocol based on the concept of secret sharing. In this paper, we show that Liu et al.’s protocol falls short of providing security requirements. More specifically, we prove that in their protocol, authenticity of the tags to the server can not be achieved and on top of that the scheme can not be used more than once. We further propose a group mutual authentication protocol for RFID tags to overcome the mentioned drawbacks and prove that our proposal is secure. The results of analyzing the performance of the proposed protocol and its comparison with existing literature indicate that it outperforms current secure RFID authentication protocols.

近年来，射频识别（RFID）系统已成为流行的识别方法。保护RFID系统安全的关键技术是标签和服务器之间的相互认证。为了提高RFID系统的效率，最近，Liu等人。提出了一种基于秘密共享概念的群组认证协议。在本文中，我们表明Liu等人的协议没有提供安全性要求。更具体地说，我们证明在其协议中，无法实现服务器标签的真实性，而且该方案不能被多次使用。我们进一步提出了一种用于RFID标签的群组相互认证协议，以克服上述缺点并证明我们的提议是安全的。