Kabel Deutschland sets new broadband speed record

Kabel Deutschland, Germany’s largest cable operator, has broken the world broadband download speed record by demonstrating rates of 4.7Gb/s.

The test was conducted on real cable infrastructure at a school in the German city of Schwerin, using currently available standards, technology and hardware. The cable plant had recently been upgraded by Kabel Deutschland (KD) to 862MHz, and the test used a combination of a EuroDOCSIS 3.0-based ARRIS C4 CMTS and 12 ARRIS Touchstone Cable Modem CM820S, each accessing eight bonded Annex A (8 MHz) channels.

The rate of 4.7Gb/s is far more than any online video needs, and also too fast for existing laptop computers to process. It is a rate that cannot be sustained in practice because there is not enough capacity within the coaxial network to provide all users with that bandwidth. But, it does highlight the potential that CMTS has using the DOCSIS 3.0 cable modem standard, especially the European version, which uses 8MHz channels, rather than 6MHz with the standard DOCSIS used in North America. But the test suggests that even with six channels, rates of over 3Gb/s are attainable. In practice, such high data rates may be allocated in short bursts to individual users for downloading a movie for example.

But, the high headline speeds also do MSOs no harm in their marketing battle with Telcos to attract both broadband and pay TV customers. Verizon, for example, offers just 300Mb/s on its FiOS service.