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gfast map nov

Dark Green: Firm commitments from incumbent: BT (10M), Belgacom, Australian NBN, Swisscom,  Austria, Bezeq Israel, Chunghwa Taiwan, Telus Canada, Telekom South Africa, SK Korea, (U.S.) AT&T, Century, Frontier, Windstream, Belgium, Omantel

Mid Pink: Smaller carriers in Germany, Norway, Finland, Japan

Light Green: Incumbent likely:  France, Germany, Italy

96 ports promised and even more sought. Burri of Swisscom confirmed he has a similar unit. Update, 7/10. Huawei has now confirmed they are shipping 96 ports. I had guessed it was Huawei in the original. end update. was designed for local distribution points serving up to 16 homes, of which British Telecom has about 4M. These are very close to the subscriber. from local distribution points delivers 500-800 megabits today and well over a gigabit very soon. The BT plans changed, going to the (much fewer) existing cabinets. 

Many buildings have more than 16 apartments. Many cabinets have hundreds.

Sckipio currently maxes out at 24 ports; Broadcom at 16. Since you can't (yet) have two DSLAMs sharing the same cable binder, that's a severe bottleneck. My building, for example, has about 60 lines on one box in the basement. In Jennie's building, 16 ports would require a vectored DSLAM on all 20 floors, an expensive job.

Huawei, Adtran, and I believe Nokia decided to solve that problem by moving vectoring from the board in the DSLAM to an external box. These were promised for 2016 but the schedule has slipped. I don't know what will be required to move from successful lab tests to volume deployment, but Linney is optimistic. 

The large vectoring port count became crucial to BT when the finance people vetoed the distribution point plan. Linney's team did the research that proved 300 meter was practical. It's now part of the standard.  

Long reach of course is slower, more like 300 megabits at 300 meters. Trevor provided initial data on 340 lines. They showed a wide range of loop losses. The majority of lines achieved the product limit of either 330Mbps or 160Mbps downstream. 99.7% (all but 1) achieved above 100Mbps. BT Openreach is working actively to develop the system for the retail ISPs (including BT Retail.)

They are geared up for the target of 10M lines.



The Site for gfast 230 News

I’m still working through remarkable presentations from the Broadband Forum events. Michael Weissman, Bernd Hesse and team did a remarkable job choosing the speakers.

Deutsche Telecom: 35b Supervectoring Delayed to 2019
Broadcom is now over 3 years late. DT briefed German reporters after their financial call and revealed 35b was now delayed until 2019. 35b should deliver 200+ meg downloads 500-600 meters, a crucial tool for DT, which is losing share to cable. Cable now covers about 70% of Germany and is expanding. DT now only offers 50-100 megabit DSL while cable is often 400 megabits, going to a gigabit. 

The problem is software; the hardware is shipping and supposedly will work. DT says 35b is not ready to turn on. Broadcom in 2015 said 35b was in "production" in the press release below. Alcatel in early 2016 said to expect complete systems very soon. "35g is very similar to 17a so there should be little delay."

Broadcom's problems are leading major telcos and vendors to have a plan B, using Sckipio DT itself is planning extensive deployments in 2019, mostly in apartment buildings.

Gigabit 100 Meters - Unless the Wires are Lousy
Speeds are fine, "Unless there's a line problem." I've been reporting for three years that ~10% of lines have problems. In the chart by Rami Verbin of Sckipio, he finds goes ~130 meters on good lines. Poor lines have about half the reach. 

His chart roughly matches the reports from Swisscom, Belgacom, and England for both & vectored DSL. The 10% with problems can cause the majority of the line-related complaints to support. The angry customers drive up cost.

Rami's solution to reach the gigabit is bonding, supported on the Sckipio chips. Verbin made some additional points:

  • 4 gigabits is possible by bonding two decent 2 gigabit lines.
  • Even in a service from remote cabinets, ~25% are close enough to get a full gigabit."
  • cDTA and iDTA are practical ways to deliver much higher upstream by switching some bandwidth from downstream to upstream only when needed.
  • 35B will probably be similar but Deutsche Telecom doesn't expect to deploy until 2019.

AT&T Wants Coax 2-5 Gigabit Very Soon.
AT&T faces intense competition from cable, talking about 10 gigabits in both directions. (Cable will only be 1 gig down, ~100 meg up, until ~2021.) AT&T wants something to brag about as well.

AT&T gained millions of lines of coax as part of the DirecTV deal. Alcatel and Huawei are leading the development of G.mgfast. That uses 424 MHz, full duplex, to achieve ~2.5 gigabits in both directions. The reach on telco twisted pair is only about 30 meters. On coax, those speeds can probably extend far enough to service most apartment buildings. Using 848 MHz, speeds can reach 5 gigabits. The ITU standards group has been aiming for 2019-2020 for G.mgfast, too slow for AT&T's marketers. David Titus wants a high-speed standard for coax "early in 2018." He believes that is "doable."

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