About the Project

Overall, the aim of this project was to survey on the positive effect that enhanced computing and security technologies could introduce to traffic security. Our team, consisting of four people including myself, focused on utilizing TEE (trusted execution environment) for digital tacographs.

Measurements of digital tacographs must be truthworthy and should not be modified. This is because even allowing the owner of the vehicle to modify it would introduce malvolent scenarios such as blaming an accident onto the actual victim. Thus, to guarantee the truthworthiness of digital tacographs, we introduced the concept of secure logging for them such that even the owner of the tacograph and/or the vehicle can neither forge nor modify the record.

What distinguishes this effort from other TEE-oriented projects is that digital tacographs have processors with significantly lower performance than others. The main challenge came from the fact that TrustZone-M, which are usually shipped with such processors, and standard TrustZone diverged more than we expected. We also wanted overhead-prone features like real-time logging not to be included in the final system. Therefore we introduced a blockchain-like structure for the log files such that any attempt to forge, remove or modify the log would cause the entire log database to be invalidated.

Contribution and Information

• Period of Contribution: 12/2021 ~ 8/2022
• Total Participants: around 4 people
• My Roles
• Devised the secure log format
• Participating author of the related patent and paper