Authentication in Electric Vehicle Supply Equipment (EVSE)

By Amit Sethi, Technical Marketing Manager, STMicroelectronics

Electric Vehicle Supply Equipment (EVSE) plays a critical role in the adoption and functionality of electric vehicles (EVs). As EV infrastructure expands, ensuring secure and efficient access to charging stations becomes paramount. Authentication in EVSE systems is essential to control access, manage billing, and protect against unauthorized use or cyber-attacks.

Authentication in EVSE ensures that only authorized users can access the charging infrastructure. Proper authentication ensures that the correct user is billed for the electricity consumed. This is essential for both private and public charging stations, as it prevents unauthorized access and potential misuse of the charging infrastructure. It ensures that data collected from the EVSE is accurate and attributed to the correct user, which allows operators to manage user profiles, monitor usage patterns, and provide tailored services.

EVSE systems can be targets for cyber-attacks. Implementing robust encryption, regular security updates, and monitoring can mitigate these risks. Trusted Platform Module (TPM) is a hardware-based security feature that can play a crucial role in enhancing the security of EVSE. The Trusted Platform Module (TPM) is a specialized microcontroller designed to secure hardware through integrated cryptographic keys. TPM provides several security functions, including secure generation and storage of cryptographic keys, measures and verifies the integrity of the system’s boot process, remote attestation and protects data by encrypting it with TPM-generated keys.

Integrating the Trusted Platform Module (TPM) into Electric Vehicle Supply Equipment (EVSE) brings a host of benefits, enhancing the security, reliability, and user experience of EV charging systems. Here are the key advantages:

Enhanced Security

TPM securely generates, stores, and manages cryptographic keys within its hardware, making it extremely difficult for attackers to extract these keys. With TPM, user authentication can leverage strong cryptographic methods, ensuring that only authorized users can access the EVSE.

It facilitates the encryption of sensitive data, such as user credentials, transaction details, and usage logs, ensuring that even if data is intercepted, it cannot be read without proper decryption keys.

Integrity and Trust

TPM can ensure that the EVSE boots only with verified and trusted software, protecting the system from malware and unauthorized modifications. Using TPM, EVSE can verify the integrity of firmware and software updates, ensuring that only authorized and untampered updates are applied.

Protection Against Physical and Cyber Attacks

Even if an attacker gains physical access to the EVSE, TPM’s secure storage makes it extremely challenging to extract cryptographic keys and sensitive information.

TPM protects against various cyber threats, including man-in-the-middle attacks, eavesdropping, and tampering with data in transit.

Improved User Management

TPM can manage digital certificates used for mutual authentication between the EVSE and the electric vehicle, enhancing secure communication.

TPM supports robust access control mechanisms, allowing operators to define and enforce detailed user access policies.

Reliable and Secure Data Handling

TPM ensures that data collected from the EVSE is accurate and has not been tampered with, maintaining the integrity of usage logs, billing information, and user data. Sensitive information is stored securely within the TPM, protected from unauthorized access and tampering.

Compliance and Standardization

Implementing TPM can help EVSE operators comply with stringent security regulations and standards, ensuring that the infrastructure meets industry and government requirements.

Standardized TPM implementations can improve interoperability between different EVSE systems and networks, facilitating a more seamless user experience.

Future-Proofing

TPM supports advanced cryptographic methods, including those that are resistant to future threats. TPM’s robust security framework can scale with the growing number of EVSE deployments, ensuring consistent and reliable security across a large infrastructure.

Integrating TPM into EVSE systems significantly enhances the security, reliability, and trustworthiness of electric vehicle charging infrastructure.

STMicroelectronics’  STSAFE-TPM system-on-chip solution, based on well-proven ST33 hardware secure element,  is widely deployed in IoT equipment, personal computers and servers, printers, telecom and healthcare devices. All STSAFE-TPM products are certified by Common Criteria, TCG and FIPS and comply with regulatory requirements.​ STSAFE-TPM offering includes products compliant with automotive and industrial environmental constraints.

Visit www.st.com for more details.