This communication system provides the transfer of over 20 S0/Up0 channels via coaxial cabel. The QPSK transfer rate in range below 100 MHz is about 10 Msymbols/sec.

The IZT Firebox is designed for long distance passenger rail services. In case of disturbances or disruptions in the train's internal communication system, the IZT Firebox separates all affected lines from the bus system and ensures full functionality of the remaining system.