Digital Tachograph

What Is a Digital Tachograph?

A digital tachographdigital tachographApplicationEU-mandated driver-hours recording smart card for trucks.Click to view → is a tamper-proof smart card recording system mandated by EU Regulation 165/2014 for commercial vehicles over 3.5 tonnes. The system consists of a vehicle unit (VU) installed in the dashboard and individual driver smart cards that record driving time, rest periods, speed data, and vehicle events. The data is cryptographically signed to prevent manipulation, and enforcement authorities use the recorded data to verify compliance with EU driving time regulations.

Card Types

The tachograph system uses four distinct smart card types, each issued by national authorities:

Each card is a contact smart card compliant with ISO 7816 containing a secure element with cryptographic keys for mutual authentication with the vehicle unit.

Data Recording

When a driver inserts their card into the vehicle unit, the VU and card perform mutual authentication using a PKI infrastructure rooted at the European Root Certification Authority (ERCA). Once authenticated, the VU continuously records:

• Driving periods -- start/end times, distance driven, vehicle registration
• Other work -- loading, unloading, administrative tasks
• Rest periods -- breaks and daily/weekly rest
• Card events -- card insertion, withdrawal, driving without a card
• Faults -- power supply interruption, sensor errors, security breaches

All recorded data is signed with the VU's private key and countersigned by the driver card, creating a tamper-evident audit trail.

Security Architecture

The tachograph PKI is a hierarchical system:

• ERCA -- European Root CA that certifies national CAs
• National CA -- issues certificates embedded in driver cards, VU units, and workshop cards
• Motion sensor pairing -- the VU and its motion sensor share a symmetric key established during installation by a workshop card holder

The system uses RSA (2048-bit in first-generation, migrating to ECC in smart tachograph v2) for digital signatures and 3DES or AES for session encryption between card and VU.

Cards are certified under Common Criteria at EAL 4+ to resist physical tampering and cloning attempts.