Method for authenticating a central unit connected to peripheral units using a secure server

A system comprising:

• a central unit, and peripheral wheel units carrying out measurements on tires that are mounted on wheels of a motor vehicle, the peripheral wheel units being wirelessly connected to one another, wherein:
• the central unit is configured to communicate an identifier and a password to each peripheral wheel unit, and authentication information to a server for establishing a secure link so that the server may recognize a peripheral wheel unit identifier of a target peripheral wheel unit of one or more of the peripheral wheel units;
• the target peripheral wheel unit being configured to generate a new random session code and sending the new random session code to the central unit;
• the central unit being configured to transmit, the central unit identifier, the peripheral wheel unit identifier of the target peripheral wheel unit, and the new random session code to the server to request a proof of authentication so that the central unit obtains administrative rights over the target peripheral wheel unit;
• the server being configured to:
• perform a first encryption using a shared encryption key recognized by a server identifier and the new random session code to form a random and shared dynamic temporary first encryption key;
• perform a second encryption using the central unit identifier and the dynamic temporary first encryption key to generate encrypted central-unit information for proof of authentication;
• and
• transmit the encrypted central-unit information to the central unit;
• the central unit being configured to transmit the encrypted central-unit information to the target peripheral wheel unit;
• and
• the target peripheral wheel unit being configured to:
• perform the first encryption using the shared encryption key and the new random session code, to form a temporary second encryption key;
• decrypt the encrypted central-unit information using the temporary second encryption key to obtain a decrypted identifier;
• compare the decrypted identifier with the central unit identifier;
• and
• authenticate the central unit when the comparison results in a match.

A method for carrying out measurements on tires of a motor vehicle, the motor vehicle including a central unit, and peripheral wheel units, the method comprising:

• communicating, by the central unit, a central unit identifier and a password to one or more peripheral wheel units, and authentication information to a server for establishing a secure link so that the server may recognize a peripheral wheel unit identifier of a target peripheral wheel unit of the one or more peripheral wheel units;
• generating, by the target peripheral wheel unit a new random session code and sending the new random session code to the central unit;
• transmitting, by the central unit to the server, the central unit identifier, the peripheral wheel unit identifier of the target peripheral wheel unit, and the new random session code to request a proof of authentication so that the central unit obtains administrative rights over the target peripheral wheel unit;
• performing, by the server, a first encryption using the shared encryption key recognized by a server identifier and the new random session code to form a random and shared dynamic temporary first encryption key;
• performing, by the server, a second encryption using the central unit identifier and the dynamic temporary first encryption key to generate encrypted central-unit information for proof of authentication;
• transmitting, by the server, the second encrypted information to the central unit;
• transmitting, by the central unit, the second encrypted information to the target peripheral wheel unit;
• performing, by the target peripheral wheel unit, the first encryption using the shared encryption key and the new random session code, to form a temporary second encryption key;
• decrypting, by the target peripheral wheel unit, the encrypted central-unit information using the temporary second encryption key to obtain a decrypted identifier;
• comparing, by the target peripheral wheel unit, the decrypted identifier with the central unit identifier;
• and
• authenticate the central unit when the comparison results in a match.