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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

3 Horse race100 meter G.fast doesn't go far enough or serve larger buildings. Perhaps the telcos want something with more reach than G.fast (100 meters, ~500 megabit,) and more speed than DSL Vectoring (~100 megabit, 800 meters.) Chipmaker Lantiq was the first to announce 200+ meg products,

Lantiq tweaked existing high end VDSL2 chip - and the pr. VDSL2 30 MHz profile 30a is generally described as 100 meg down, 100 meg up. Combine the two for your press release and you're at "200 megabits." Tweak a few parameters and you can claim "300 Mbps VDSL Right Now." Lantiq did that. Besides one-upmanship, it provides a way to telcos to advertise "300 megabits" to counter cable promises of 200, 400 and even a gigabit. Aethra, working with Lantiq, has delivered units to Orange Poland.  I believe Broadcom is doing similar. < Kabel Deutschland CTO Lorenz Glatz two years ago explained his company strategy. "Whatever speed Deutsche Telekom, we'll offer twice the speed at the same price." Euro-DOCSIS 3 easily goes to 400 shared and delivers > 200 meg 95+% of the time. In 12-24 months, DOCSIS 3.1 will take that to a gigabit. Deutsche Telekom, building a 50-100 megabit VDSL network, fears they'll be left behind. Vendors are listening and hence promising a new class, Midi-DSL, mid-range bet G.fast and G.vector, promising higher speeds. Alcatel, Huawei and Adtran have all announced products. For now, Midi-DSL is slideware.

 No one has shown equipment publicly although Huawei claims tests in customer labs.

    Midi-DSL isn't limited to 16 connections. 100 or more homes can be served. It may be years before G.fast can do more than 16 homes. There are problems with space, heat and design. Midi-DSL is planned for cabinets which have more room for heat sinks and boards. 

   Much of the improved speed is hype: DSL has always been discussed based on download speed (6 meg for ADSL1, 24 meg for ADSL2 ...) The Midi-DSL folks add the upstream speed to get more impressive numbers. Since some of the upstream capacity in G.fast can be switched to downstream giving the combined figure isn't totally deceptive. But it's darn confusing. I'll keep reporting downstream & upstream numbers for now.

    Higher speeds require using more spectrum, becoming more efficient, or reducing interference. G,vector is standardized to 30 MHz but most deployments only use the lower 17. I have separate articles on Lantiq, Adtran, aethra, Alcatel and Huawei with more details.

 

 

The Site for gfast 230
 

G.fast 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. http://bit.ly/BBFBASE

Deutsche Telecom: 35b Supervectoring Delayed to 2019 http://bit.ly/35blater
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 G.fast. DT itself is planning extensive G.fast deployments in 2019, mostly in apartment buildings. http://bit.ly/35blater

Gigabit 100 Meters - Unless the Wires are Lousy http://bit.ly/gflousy
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 G.fast 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 G.fast & 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. http://bit.ly/gflousy

AT&T Wants Coax 2-5 Gigabit G.fast. Very Soon. http://bit.ly/ATTCoax
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."http://bit.ly/ATTCoax

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