Identity authentication method and device

Abstract

Embodiments of the invention provide an identity authentication method and device. The method comprises the steps of determining signal intensity of a received response signal sent by a second authentication object and a signal to noise ratio corresponding to the signal intensity, wherein the response signal is used for responding to a search signal sent by a first authentication object; and authenticating the identity of the second authentication object according to the signal intensity of the response signal and the signal to noise ratio and standard signal intensity as well as standard signal to noise ratio. If the signal intensity of a response signal received by the first authentication object (such as a car) is greater than the standard signal intensity, but the signal to noise ratiothereof is less than the standard signal to noise ratio, the first authentication object receives relay attack, then authentication of the second authentication object by the first authentication object fails, so as to prevent relay attack in identity authentication.

Description

technical field [0001] The invention relates to the field of communication technology, in particular to an identity authentication method and device. Background technique [0002] The car keyless entry system (Passive Keyless Entry and Drive System, PKED) allows users to remotely unlock, lock and start the engine when it is inconvenient to take out the key. Common PKED systems such as figure 1 As shown, it is composed of a remote control key and a body control module. The remote key and the body control module perform information interaction, and then the MCU (Microcontroller Unit, micro control unit) performs information processing and authentication, and finally the body control module controls the opening and closing of the car door. The start of the engine. [0003] The specific information interaction between the remote control key and the vehicle body is as follows: figure 2 As shown, the vehicle periodically transmits LF (Low Frequency, low frequency) search signa...

AI Technical Summary

Problems solved by technology

[0006] In the relay attack method, the attacker does not modify the communication content between the remote control key and the car, but uses a man-in-the-middle method to make the car and the remote control key think that they are within a certain area, even if the remote control key and the car The use of complex cryptographic algorithms cannot resist the attack

[0007] Since the relay attacker uses the signal amplifier to enhance the signal energy, the method of obtaining the position parameters of the remote control key from the signal strength and signal direction cannot effectively resist the relay attack

The speed of electromagnetic waves is 3×10 8 m / s, so confirming the relay attack from the perspective of ToA requires a timer with high precision, and the cost is also high

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