A New Unpredictability-Based RFID Privacy Model

A new unpredictability‐based radio frequency identification forward privacy model and a provably secure construction

“…Yang et al . have proved that their unp τ ‐privacy model is stronger than both ind‐privacy and unp*‐privacy . Therefore, once we can show unp f τ ‐privacy is stronger than unp τ ‐privacy, then it is stronger than ind‐privacy and unp*‐privacy.…”

“…In this section, we first revisit Yang et al . 's unp τ ‐privacy model , which has already been shown to be stronger than ind‐privacy , unp‐privacy , and unp*‐privacy . We then propose a counter‐example protocol, which can be proved to be unp τ ‐private but not forward private.…”

“…As stated by Yang et al . , the unp τ ‐privacy model is sufficient enough for the basic privacy of RFID tags, that is, no adversary can trace any tag if the adversary has no ability to corrupt the tag. It is also proved to be stronger than previous indistinguishability‐based and unpredictability‐based privacy models, which means it can capture more practical attacks.…”

“…In order to preserve the privacy of RFID authentication systems, many privacy models have been formalized in the literature, for example, . Among them, there are five main categories, indistinguishability‐based models , unpredictability‐based models , simulation‐based models , universal composability‐based models , and zero‐knowledge‐based models . These privacy models have captured strong adversarial capabilities regarding tag anonymity and untraceability.…”

“…In 2013, Yang et al . polished unp*‐privacy to be unp τ ‐privacy. In the unp τ ‐privacy model, adversaries are allowed to observe the decisions of a reader and any tag, that is, “accept” or “reject”, while this ability is not permitted in some other unpredictability‐based privacy models such as unp‐privacy, eunp‐privacy, and unp*‐privacy.…”