Approaches for BestEffort RelayResistant Channels on Standard Contactless Channels Relay attacks is a serious and practical threat to contactless systems that is becoming more attractive with the increased use and transaction value of contactless payments. Distancebounding is a countermeasure widely studied in academic research but it has not transferred to commercial systems. Conventional communication channels cannot achieve the theoretical properties often required for the protocol to be secure and special channels might not be feasible to adopt. Our objective is to design xe2x80x98besteffortxe2x80x99 distancebounding channels suitable for real RFID systems. In this paper we discuss standard channel implementation using offtheshelf emulators and readers, and discuss potential modifications to channels implementable on current devices that would results in more relayresistant channel designs. We are present reference relay attacks for ISO 14443A and Felica type systems using our implemented devices.

An UltraLightweight RFID Mutual Authentication Protocol In some applications of the Internet of Things (IoT), for privacy preserving and authentication of entities, it is necessary to use ultralightweight cryptographic algorithms. In this paper, we propose a new ultralightweight authentication protocol between RFID components, in which only simple operations are used. In this protocol, the server has access to the data gathered by the tag in the same authentication phase through the reader interface, instead of sharing a secret key. The proposed protocol is secure against several attacks, such as replay attacks, denial of service, offline guessing attacks, modification attacks, full disclosure attacks and impersonation attacks, in addition to its practicality when compared to the previously proposed RFID authentication protocols. It also provides anonymity of tags against readers and the other tags involved in the protocol.