High-speed data transmission.

High-speed data transmission.

Reliable and secure.

Dark fiber for high-speed data


We have been leasing the free transmission capacity of fiber-optic cables – technically known as dark or unlit fiber – to our customers since 1996, including mobile telephony providers, cable network operators, computer centre operators, and other commercial customers. Our fiber-optic cables comply with standard G.652 defined by the ITU (International Telecommunication Union) and boast very favourable mechanical and optical properties – for example low attenuation and optimum parameters for light dispersion. Further benefits of our network include its high availability, which is an impressive 99.99% – far exceeding the standard level in the sector. We therefore ensure the optimum conditions for fast and secure data transmission.

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Data rates into the terabit range

Our customers can lease unused fibers in our fiber-optic connections in pairs and build networks using their own technology. To this end, we make technical sites available for you throughout Germany.

Depending on the components used for the data transmission and preparation, you will enjoy transmission rates in the region of 100 gigabits per second per wavelength. And of course, the flow of data doesn't suddenly stop when it reaches the limits of our network: We cooperate with a large number of German and European network operators, so we can connect to all main exchanges and link up with international networks.



Many regions in Germany are not yet linked up to the national high-speed networks – the major telecom providers have little interest in rural areas outside of cities and towns.

We always keep an eye on our network: The Pipeline Dispatching Centre monitors not just the pipelines – staff in Kassel work 24 hours a day, 365 days a year to ensure that data as well as gas can continue to flow without interruption.

Tailored. Flexible. Open. Our customer service team is there for you – and with over 20 years of experience, we combine your needs with our know-how to create solutions.