Protection of image and measurement data in an open network for traffic enforcement

Efficient traffic enforcement requires measuring systems using digital cameras instead of wet film technology. The digital file containing the image data and the measured speed and/or other values are transferred to a central office without personnel at place. A type approval for such a system – as necessary in most countries – has to ensure the authenticity and integrity of these data with the goal of being accepted as evidence at court. The company Robot has developed a speed-measuring instrument using a digital camera system that has been type approved by PTB and is used by the German police since 2003. This paper firstly presents the technique of this system as an example to protect these data. The second part describes the in-depth validation method performed at PTB in the framework of the type approval procedure with the focus on the analysis of securing means of the operating system and of the applied cryptographic algorithms. The basis is a detailed and structured set of specifications and requirements that has been drafted by a consortium within the project VERA 2 funded by the EC.