General Information; Purpose And Scope; Figure 1. Connection Scheme With St25Dv-I2C-Disco - ST ST25DV-I2C User Manual

1

General information

This document is applied to STM32L476 Arm
Note: Arm is a registered trademark of Arm Limited (or its subsidiaries) in the US and/or elsewhere.
1.1

Purpose and scope

The "ST25DV-I2C Crypto Demo" runs on the ST25DV-I2C-DISCO kit, featuring a ST25DV-I2C tag connected to a
STM32L476 device through the I2C bus. The ST25DV-I2C-DISCO kit represents an IOT sensor device, which is
controlled by an Android™ smartphone through the NFC.
When a communication between the device and a smartphone is started, a mutual authentication is done. It
ensures that:
• The user of the smartphone has a permission to communicate with this device
• The device is not counterfeited
Once the mutual authentication is done, all the communications between the microcontroller and the Android™
phone are encrypted, so the user can configure the product or retrieve data securely. Anyone who spies on the
data exchanged on the NFC is not able to interpret them. The key used to encrypt the communication changes
each time a mutual authentication is done, this action prevents someone from recording the encrypted content
and replaying it.
In this demonstration, the first user of the device becomes the administrator of the product so the device refuses
any request from other users.
More details on the cryptographic processing used in the demonstration are provided in
processes.
Additional details on the implementation are provided in the AN5323 ST25DV-I2C crypto demonstration.
UM2575 - Rev 1
®
-based devices.
Figure 1. Connection scheme with ST25DV-I2C-DISCO
NFC
Secure transfer
channel
ST25DV-I2C-DISCO
I2C
STM32 device
ST25DV-I2C
UM2575
General information
Section 2 Security
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