Date Added: Jan 2010
In this paper, the authors propose a grouping-proof protocol for RFID tags based on (n, n)-secret sharing. Their proposed protocol addresses the scalability issue of the previous protocols by removing the need for an RFID reader to relay messages from one tag to another tag. They also present a security model for a secure grouping-proof protocol which properly addresses the so called mafia fraud attack (sometimes called distance fraud) which is a simple relay attack suggested by Desmedt. Any location-based protocol including RFID protocols is vulnerable to this attack even if cryptographic technique is deployed.