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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

Les BrownInspired by strong customer desire. The original plan for 8-16 ports isn't nearly enough now. BT and others have decided to use far fewer terminals, each with more lines. Vectoring 48 or 96 lines is not a trivial problem. Imagine the calculations for so many lines running at 500 megabits over 106 MHz. The heat alone is a problem for small field terminals. It will require at minimum semi-custom chips optimized for the application. 

Huawei is confident that "long reach" will soon see improved performance. Confirming the early field trials at BT, they expect it will be practical to increase the power used by a few dBm. My cable friends are working on 2 gigabit systems, possibly using full duplex technology.

Sckipio suggested last year they were close to vectoring 48 lines using dedicated processors. Now, Huawei's Jack Zhu tells me they have a 96 port unit on the roadmap for Q4 of this year, based on Broadcom chips.

A master vectoring engine will control four boards with 24 ports each. Zhu spent nearly a decade supporting access networks at BT for Huawei and closely watches what the carriers require. Speaking from China, he tells me the Europeans want both more ports and higher performance at 300-500 meters.  

Interoperability remains a problem, although Swisscom has had some success using CPE from a different vendor than the DSLAM. The Broadband Forum continues interoperability testing with the University of New Hampshire, but the carriers need to be more demanding to get the chipmakers to work together well. 

Britain has the greatest diversity, testing DSLAMs from Alcatel, Huawei and Adtran. I believe the Alcatel and Huawei units are using Broadcom chips and Adtran Sckipio chips. Broadcom's chip supports VDSL as well as, a major advantage in mixed networks. Although Sckipio's chip may have better performance, many customers prefer the flexibility of continuing support of VDSL.  

Once 48 and 96 ports ship, watch the big telcos ask for more.


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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