Passive RFID Tag Revocation Checking via Low Power Display

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Passive RFID tags face challenges in revocation and expiration checking due to limited storage and lack of self-sustaining power, making them vulnerable to revoked reader attacks, as they rely on readers for time and date information, which can lead to insecure certificate validation.

Innovation Solution

Involving the user in the authentication protocol using hash chains and cryptographic signatures, combined with a low-power, ultra-thin display on the RFID tag powered by the RFID antenna, allows for efficient and timely revocation and expiration checking of reader certificates with constant communication overhead, ensuring secure information transmission.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If RFID tags rely on readers for time and date information, then power consumption is reduced and device complexity is minimized, but security reliability deteriorates due to vulnerability to revoked reader attacks and undetected expired certificates

Engineering Contradiction:

Improvepower consumptionVSAvoidsecurity reliability

Core Design Contradiction:

Use of energy by moving objectVSReliability

Solution Approach 1:

The patent introduces a display device as an intermediary component that visually presents certificate validity information to the user. This mediator allows the passive RFID tag to maintain low power consumption while the display provides security verification capability, resolving the contradiction between energy efficiency and security reliability.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The system implements feedback by displaying certificate expiration dates and validity status to the user. This visual feedback loop enables users to verify reader credentials without requiring the RFID tag to actively maintain security state, thus maintaining low power consumption while improving security reliability through user awareness.

Inventive Principle:

Principle #23Feedback

2Device complexity

If RFID tags have limited storage capacity, then device complexity and cost are reduced, but the ability to store and verify revocation lists and certificates is compromised

Engineering Contradiction:

Improvedevice complexityVSAvoidrevocation list storage

Core Design Contradiction:

Device complexityVSLoss of information

Solution Approach 1:

The patent shifts the storage dimension from the RFID tag to the reader device. Instead of storing revocation lists on the constrained tag, the system stores comprehensive revocation data on the reader with sufficient storage capacity, then transmits only essential validity information to the tag for display. This dimensional shift resolves the storage capacity limitation while maintaining security verification capability.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

3Device complexity

If RFID tags lack online communication channels, then device complexity and power requirements are minimized, but the ability to perform real-time revocation checking is lost

Engineering Contradiction:

Improvedevice complexityVSAvoidrevocation checking capability

Core Design Contradiction:

Device complexityVSReliability

Solution Approach 1:

The system performs preliminary action by having the reader transmit certificate and revocation information to the RFID tag before authentication occurs. This advance preparation allows the passive tag to verify reader credentials offline without requiring real-time online communication, thus maintaining low device complexity while enabling revocation checking capability.

Inventive Principle:

Principle #10Preliminary action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This solution provides robust security guarantees by enabling timely and efficient revocation status checks, preventing information disclosure to readers with revoked or expired credentials, and minimizing communication and storage overhead, applicable to various RFID applications including e-passports and credit cards.

Implementation Method 1

Methodology Applied

Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentUS8710952B2RFID reader revocation checking using low power attached displays

Publication Date: 2014.04.29 RGT UNIV OF CALIFORNIA

AI summary

A method of authenticating a radio frequency identification (RFID) reader to efficiently and timely check of revocation status of the RFID reader includes the steps of checking whether a given certificate is expired or revoked, and allowing a user of an RFID tag to verify that the credentials and revocation status information reported to the tag by reader is correct and current/valid before permitting information transmission from the RFID tag to the reader. An RFID tag includes a passively powered display and a user activatable control which allows the method to be carried out with the tag. The tag may include encrypted communication ability and automatic certificate revocation list checking. (This method is applicable not just to RFID but to any technology involving purely passive operation, i.e., where the tag obtains power from a reader).