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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

Longer reach, reverse power, downloaded upgrades for the customer equipment, DTA over coax, and a dozen other improvements. The updated standard was pretty much agreed last week at an ITU SG-15 meeting in Geneva. The major chip vendors, Broadcom and Sckipio, are already hard at work. The carriers are hoping for equipment in the second half of 2017.

I have hundreds of pages of proposals from some very good engineers so this is just the first pass. Amendments one and two were approved. Amendment three was consented but very few changes are likely before final approval. 

BT needs longer reach. Their finance guys insist they use existing cabinets rather than building to the distribution points closer to the customer. was designed for 50-200 meters but existing cabinets are often 350 meters away or more. The new standard increases the maximum transmit power up to +8 dBm, with a practical goal of 300 megabits 300 meters. See BT Musts: ~ 350 meters, 48/96 ports. I didn't (yet) see anything about more ports, perhaps because that was possible without any updates. Broadcom had promised 96 port systems in Q4 2016 using external vectoring engines but the schedule has slipped. 

AT&T has been vocal they want a true gigabit to compete with cable, not "up to a gigabit." Comcast offers gigabit downstream in parts of Atlanta, Nashville, and Chicago, with Detroit scheduled next.

They are ready to go wide and have promised to offer the gigabit to more than 40M homes by 2018. For now, upstream is limited to 35 megabits; Jorge Salinger just predicted they will be bonding for 400 megabit upstream late next year. They aren't waiting for full duplex, still several years away. 

Cable versus telco is not the same thing as a monopoly. Larry Babbio told me they built FiOS because "We have to get cable out of the home." They were responding to Cablevision winning away customers in Long Island. Comcast came back by moving to DOCSIS 3 years before expected. In early 2015, AT&T was telling Wall Street  45 megabit U-Verse would be competitive. A few months later, they realized DOCSIS 3.1 was coming fast and they responded with a move for 12M lines of fiber. 
Our prices are 50% to 100% higher than more competitive countries in Europe, good evidence our competition is very weak. In practice, U.S. cable and telco have agreed to both raise prices regularly. No one needed to meet in obscure airport motels to form a cartel which would be illegal. Instead, they publicly signal. The competition authorities are afraid to bring a case like that to trial.
While they don't compete on price, they do upgrade technology to win or at least customers. Deutsche Telecom has a monopoly on four million German homes; they plan to offer maximum speeds of 3-6 megabits into the next decade. Across about a quarter of the U.S., the telcos have decided to abandon landlines and sell more wireless. Most of those can get cable, which covers 92% of the U.S. and have a robust but expensive choice. 


The amendments extend the frequency range up to 212 MHz. That will almost double speeds on very short loops, such as the apartment buildings AT&T is planning to serve. In an early draft, the committee chose to continue with linear precoding; I'm not sure about the final version but it's probably the same. 

There are many pages of new specifications for reverse power, downloaded upgrades of customer equipment, and signaling. I'm sure I'll be finding more items as I make my way through the documents. I'm not sure whether the proposal for more bits per signal was included. Pointers welcome.

The next meeting will be 14-18 November in Hangzhou, hosted by Huawei.

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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