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As HYBNET (of hybrid broadband network ) which is ARD -internal optical fiber designated -Leitungsnetz that the connected sites ( radio stations connecting) together. Some of the regional broadcasting corporations of the ARD operate their own networks in their catchment area, which are based on structures similar to the Hybnet.

Idea and development

Due to a requirement of the European Commission at the beginning of the 1980s, the then Minister for the Post and Telecommunications of the Federal Republic , Christian Schwarz-Schilling , initiated and strictly promoted the liberalization of the post and telecommunications system in Germany. After it became clear around 1988 that after the loss of the transmission monopoly of the Deutsche Bundespost , private network carriers would also be possible in the future, Bayerischer Rundfunk, under the leadership of its technical director, Frank Müller-Römer , dealt intensively with questions of the planning and future operation of its own radio digital transmission network, which should connect the different locations of the public broadcasting corporations. In this way, the television and radio transmissions as well as the communication between the broadcasting corporations could take place on their own, much more cheaply. The ARD set up a working group under the direction of Müller-Römer, which worked out the basis for a tender for an integrated digital transmission network (HYBNET) by 1996. The ZDF was eliminated at the start of the project work of the working group. T-Systems won the tender in 1999 . The commissioning took place in 2002/2003 by Media Broadcast . A few years later, the network structure was expanded and optimized.


The basic technology of the Hybnet is SDH on the hierarchy level STM-16 with a nominal data rate of almost 2.5 Gbit / s. The physical network topology is designed in the form of two rings. Leipzig, Berlin, Hamburg, Bremen, Cologne and Frankfurt am Main are connected to the Nordring, while the Südring shares the Frankfurt am Main - Leipzig link with the Nordring and connects Saarbrücken, Baden-Baden, Stuttgart and Munich. Each segment of the rings consists of disjoint (spatially separated) laid glass fibers , which enable 1 + 1 protection of the physical connection.

Network in the network

As a "network for everything", the HYBNET provides various services, some of which were previously operated as independent networks.

  • The permanent line networks for radio and television , formerly operated by the Deutsche Bundespost and Media Broadcast, were mapped with their logical star-shaped topology . The connection and disposition of these lines takes place in Frankfurt am Main in the TV and radio star point of ARD on the premises of Hessischer Rundfunk .
  • The distribution of the first ARD program, which was handled in Frankfurt am Main, to the broadcasters in a logically ring-shaped network (television distribution).
  • The Corporate Network (CN) provides the ARD broadcasters and partner stations ( ORF , SRG ...) with ISDN connections via their own hardware. Separate breakout points to the PSTN enable optimized and fail-safe call routing.
  • Using the integrated ATM are IP -Traffic and permanent and temporary audio and video services in real time (audio and video lines) settled. Via the broadcast service multiplexer from Telekom ATM Broadcast Services, users can set up audio and video connections in self-dialing mode.


The Hybnet has been operated by Media Broadcast on behalf of ARD since it went into operation in 2002/2003 and administered by the ARD star . Since January 1, 2011, the broadcasting corporations of ARD, Deutschlandradio and Deutsche Welle have been using the broadband transmission network "HYBNET-Neu" implemented by Vodafone with a fiber optic / DWDM infrastructure that provides a total transport capacity of 98 times 10 Gbit / s . The actual television, radio and transport services are mapped using IP / MPLS technology. The successor "HYBNET III" has been in operation since the beginning of 2019.

The introduction of HYBNET has led to significant cost reductions for ARD in the areas of program delivery, program exchange, telecommunication services and data transport, as well as personnel savings in the control rooms entrusted with the broadcasting, totaling tens of millions annually.

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