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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

Saturn VCustomers want 212 MHz but development is still needed. Tom hopes for the first half of 2018, but notes, "The timetable for volume deployment is dependent on the chip suppliers." One European telco was told not to expect much until well into the year. I wouldn't be surprised if few customers are connected until late in the year. 

Adtran demonstrated two DSLAMs with Deutsche Telekom. One used Sckipio chips and delivered DTA. DTA allows higher effective speeds by allowing different upstream/downstream splits for each user. Since most systems are configured for a 5-1 or higher upstream/downstream split, the improved upstream can be 5X. 

The second DSLAM used Broadcom chips and 212 MHz of spectrum but without DTA.

212 MHz, in theory delivers almost twice the bandwidth of 106 MHz, raising speeds on very short loops to ~1.5 GHz and higher. The higher speeds of course require a much more robust vectoring engine; until that's demonstrated, everyone will be cautious. AT&T just made a major announcement of at 500 megabits; they don't think the faster gear is ready.

The chips and equipment will soon be available, but the systems will require substantial additional development work. The step from a single line demonstration to 16 and 48 ports will be particularly challenging given the calculations necessary for high speed vectoring, 

Let's see what Broadcom and Sckipio bring to the October BBWF in Berlin. Adtran, Calix, Huawei, Nokia, Xyzel, and ZTE will also be exhibiting.  The Broadband Forum will have a special event, BBF Access Europe, and an interoperability demonstration. On the 29th, the Forum will come to Las Vegas for a BBF Access North America. (Don't be confused by the similar names. BBF is the industry organization once known as the ADSL Forum but renamed to the Broadband Forum when fiber became important. The BBWF is a conference run by Informa.)

Salesmen are making promises but engineers are looking for proof. 

(Incidentally, this year's BBWF has a strong group of telco speakers. If I have the travel funds, we'll go.) 

Stanton and his engineers were interesting to listen to at the Adtran Huntsville event, but the real highlight was the dinner at the Space & Rocket Center underneath the 350 foot Saturn V - a real one. Until you've seen it, you can't imagine just how large it is.


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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