Gigabit DSL: The technology is ready for practice, but experts doubt demand and profitability

Gigabit DSL: technology available, but experts doubt demand and profitability

With an even wider frequency band than the VDSL technology G.fast gigabit level achieved on the copper pair. So they trumped cable connections. But some experts still see no applications for such high data rates.

The G.fast technique by means of which read be achieved Gigabit speeds over ordinary copper wire pairs for short distances, gradually makes its way to the practical use. For traditional network operators who only have telephone lines to subscribers, it appears very tempting because it seems cheap compared to the fiber-optic expansion and the use of copper pairs can still extend several decades.

However, experts disagree about how the technology really efficient over fiber-optic connections strikes and whether G.fast is already really needed - yet there are no applications that require several hundred Mbit / s, is a popular objection. This argument can nevertheless easily refute: A single such bandwidth-hungry application, there is not (example: fast, online backup are useful, but slow online backups tuns too), but many small and medium-sized companies and even ambitious budgets come with VDSL and even with normal Internet use only bad because the connections to many users prove VDSL vectoring same time. Or because the users emphasize immediate transfer of very large files, either by the company into the home office or from home to the cloud.

A common solution to this dilemma are cable connections that reach at least in the receive direction currently up to 200 Mbit / s and have already achieved twice in experiments. In the medium term aim for cable operators to 1 Gbit / s. In countries with strong competition (the Netherlands, Austria, Great Britain, ...) Cable operators recorded currently three times as many new broadband subscribers as the long-established telcos to new DSL subscribers. G.fast should therefore appear mainly to network operators as a rescue, shrink the number of participants in favor of cable operators and at the same time shy away from investing in fiber-optic expansion.

Gigabit level G.fast developers come the way in that they add up transmit and receive directions courageously. On routes to around 200 meters come with selected good copper lines as 1000 Mbit / s together. The transmitting and receiving direction can freely configure network operators within wide ranges. What you can expect from G.fast, such as new rates or higher uplink speeds, we have in the post "Gigabit Internet to the telephone line: What G.fast promises" illuminated.

Saving electricity to customers' costs

But some G.fast installations could be more expensive than fiber-to-the-home, so fiber optic connections to the home, says Rupert Wood by Analysis Mason. Glass fibers must be performed for G.fast in 200 to 250 meters to households. In some cases, it may then be cheaper, not to lay equal to the customer. Because of the installation costs come at G.fast also investments for the FTTdp-cabinets (Fiber To The Distribution Point), so the converters which convert the electrical signal from the customer to the optical signal and pass it to the core network of the operator.

Although they are designed over the developed DSL DSLAMs from the perspective of network operators smarter because they receive power through the phone line from the customers and thus lower operating costs at Telekom & Co cause, but remains the thick chunk for equipment purchase, installation, setup and maintenance. Therefore, experts estimate that the cost of G.fast connectors in the middle between VDSL and fiber optic connections (FTTH) lie. Ronan Kelly by the network supplier Adtran says that VDSL suggests 300 to 500 US dollars per person to book, FTTH with 1,200 to 1,600 US dollars.

Seven in one fell swoop

However, some network operators rely on G.fast. Here, not even the chip maker with their G.fast blocks ready, so equipment costs are still open. Broadcom, HiSilicon, Ikanos, Lantiq, Metanoia, Realtek and Sckipio - - So far, the protagonists have only completed the first interoperability tests. With the start of mass production observers expected until the second half of 2015. Sckipio thinks nevertheless, can promise connection costs at the level of VDSL.

Nor the mass production has not started, but the chip maker Sckipio believes that connection costs for G.fast will be at the level of VDSL connections. Nor the mass production has not started, but the chip maker Sckipio believes that connection costs for G.fast will be at the level of VDSL connections. Network operators attracts the company also with shorter installation times compared to the glass fiber.(Picture: Sckipio)

After all, network operators can already check in their own field test whether and how well the sale of the hardware manufacturers are for their own purposes. For example, the Dutch KPN, British Telecom and the German telecom field test started in Europe, Telekom Austria.

British Telecom wants in the UK over the next ten years "a large part" connect households with G.fast connections to the Internet. Two field tests in Huntington, Cambridgeshire and Gosforth, Newcastle should bring clarity about the feasibility of the technology this summer. About 4,000 homes and businesses will then also give information about what can actually deliver for speeds G.fast. If the test runs are positive, the large-scale use is to begin in 2016 or 2017th

Gigabit level to 66 meters

Initial experience in a laboratory environment collected BT in September 2014. Over a 19-meter course delivered prototypes downstream about 800 Mbit / s and upstream over 200 Mbit / s. To 66 meters by 700 and 200 Mbit / s were recorded. In Switzerland, Swisscom has its first field test involving customers started in late April. In the village of beavers Buchegg the community, which has around 250 inhabitants, customers surf via G.fast with up to 500 MBit / s.

If and when G.fast is in Germany, is open. Interested operators must weigh not only costs against benefits, sodern probably wait for a regulation of the Federal Network Agency. G.fast also caused due to the high frequency operation strong crosstalk interference and may only be used in vectoring mode, therefore, the lower the interference by coordinated signal transmission. Because the coordination on the current design can only be done centrally by a single network operator, this also has the authority over an entire bundle of cables. Thus under such conditions but competition is maintained among network operators, the Agency has established appropriate rules already for VDSL vectoring. For G.fast they might look similar.(Dz)