Untangling RFID Privacy Models

Abstract

The rise of wireless applications based on RFID has brought up major concerns on privacy. Indeed nowadays, when such an application is deployed, informed customers yearn for guarantees that their privacy will not be threatened. One formal way to perform this task is to assess the privacy level of the RFID application with a model. However, if the chosen model does not reflect the assumptions and requirements of the analyzed application, it may misevaluate its privacy level. Therefore, selecting the most appropriate model among all the existing ones is not an easy task. This paper investigates the eight most well-known RFID privacy models and thoroughly examines their advantages and drawbacks in three steps. Firstly, five RFID authentication protocols are analyzed with these models. This discloses a main worry: although these protocols intuitively ensure different privacy levels, no model is able to accurately distinguish them. Secondly, these models are grouped according to their features (e.g., tag corruption ability). This classification reveals the most appropriate candidate model(s) to be used for a privacy analysis when one of these features is especially required. Furthermore, it points out that none of the models are comprehensive. Hence, some combinations of features may not match any model. Finally, the privacy properties of the eight models are compared in order to provide an overall view of their relations. This part highlights that no model globally outclasses the other ones. Considering the required properties of an application, the thorough study provided in this paper aims to assist system designers to choose the best suited model.

Unpicking PLAID: a cryptographic analysis of an ISO-standards-track authentication protocol

“…One might expect that there should be easier approaches to obtaining secure authentication and key exchange protocols. Indeed, it seems that this problem, and even approaches offering enhanced privacy, have been discussed for a long time in the RFID community-see, for example, [Jue06] for an early survey and [CM13] for a more recent one. Identifying specific protocol solutions from that area and discussing their security and efficiency features, however, is beyond the scope of our analysis of PLAID here.…”

Security Attacks and Enhancements to Chaotic Map-Based RFID Authentication Protocols

“…He/she can also retransmit the messages maliciously to interrogate the tag or the back-end server in order to impersonate the reader or the victim tag. Several security and privacy issues and adversarial models are addressed in [22,19,5,31,15] in details. In this paper, we consider the following security and privacy notions in the security analysis of authentication protocols.…”

A Forward Privacy Model for RFID Authentication Protocols

“…If the normal execution securely updates the secret key of the reader and tag, this results in the privacy of the challenge tags for the type 2a and 2b protocols. The adversary A 3 can obtain the secret key of the target tag and easily break the privacy for type 0 protocols (e.g., SK-based protocol [9,5]). …”

“…Since 2003, many RFID authentication protocols have been investigated and several protocols have been shown to be insecure (see [5]). The security of these protocols is evaluated by using a cryptographic security model and one of the goals of the RFID authentication protocol is to satisfy this model.…”

“…In particular, their result showed that authentication protocols which have a key update mechanism and resynchronization property, satisfy only wide-weak privacy, which can be achieved by protocols in which the secret key is always fixed. Coisel and Martin suspected that the provable security level of the SK-based protocol [9] (which does not require any secret key update) and O-FRAP (key update mechanism is clearly shown) are equivalent [5].…”