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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 Green: Smaller carriers in Germany, Norway, Finland, Japan

Light Green: Incumbent likely:  France, Germany, 

35b tones200 megabits+, old modems still work. G.fast is headed over a gigabit on short loops  35b was introduced in 2014 as a simple, fast, low cost upgrade that could more than double speeds on existing VDSL lines. It uses 35 MHz of spectrum rather than the 17 MHz of most European VDSL builds but otherwise is nearly the same. Chipmakers - several now out of business - promised chips ready to deploy by 2016. 

Simulations suggested 35b speeds could go up to 350 megabits over short distances. Adtran shared with me test results showing 200-250 megabits+. Alcatel/Nokia had similar results. Both were very confident a year ago. Until DT commented it would be 2018, that seemed reasonable to me. 

In the picture, the green middle row is 17 MHz VDSL, deployed by the millions in Germany and elsewhere. Above that, in red, is G.fast. You can see the G.fast tones are wider than the VDSL. That makes it impractical to do effective noise canceling (vectoring) between the two systems. Unvectored VDSL typically runs at about half the speed.

On the other hand, 35b, the blue line beneath, uses the same tone spacing as the 17 MHz. In theory, that meant they could work well when lines share the binder. Apparently, no one understood the problem. Deutsche Telekom recently said 35b would not be deployed until 2018. Everyone's mum about the cause, but DSLAM vendor Adtran confirms the delay.

Several telcos are enthusiastic because it means they don't have to upgrade their existing customers. Deutsche Telekom is enthusiastic about 35b because they don't want to spend the money upgrading the older modems.

There's an excellent introduction to G.fast by Keith Russell, Paul Spruyt, and Stefaan Vanhastel of Alcatel, now Nokia, from 2014 that remains on target today. The illustration is from that article. Two things have developed since. G.fast has improved the performance at 250-350 meters, to roughly match 35b. In addition, Sckipio believes the 350-500 meter performance of G.fast could be similar to 35b under similar conditions. All this remains to be proven by field tests.  

 
 

The Site for gfast 230
 

G.fast News
A remarkable 400 people attended the very strong Broadband Forum BASE events in Berlin and Las Vegas. Trevor confirmed BT would pass the million this year. Cioffi projected “Waveguide DSL” could carry 10 gigabits a kilometer as well as a terabit 100 meters. Werner sees a 4X improvement in upstream with cDTA. Much more in next issue.

Deutsche Wants a Gigabit, Finally Realizes 50 Meg Isn't Enough http://bit.ly/2zeZ5oZ
Deutsche Telekom is finally realizing that 50 megabit DSL won't make it against gigabit cable. VP Franz Seiser is blunt. "We must change radically, become disruptive and, above all, throw away things," he proclaims at BBWF. After years of DT insisting 50 megabits is plenty, we now hear "it is about Gigabit products" from DT's Robert Soukup.  
    A lucky building in Frankfurt will receive 500+ megabit service as ultra-conservative Deutsche Telekom experiments with G.fast. Soukup told BBWF, "We're going to have a field test in Frankfurt with G.fast and Fiber To The Building (FTTB.) We will know by the end of the year if this is the right way to go." Hint to Soukup: Yes it is. G.fast is working well at a dozen telcos I;ve talked to.
     The details are surprising. DT is going for CORD, Open Source, Calix, and Radisys. http://bit.ly/2zeZ5oZ

*** The new Telebyte Guide to Testing Gfast follows the Broadband Forum IR-337 Gfast test specification, the same used by the University of New Hampshire (UNH-IOL) for Gfast certification testing. Free download http://bit.ly/telebyte (ad) It is the best technical guide to G.fast  I have seen. Grab it. Dave

1.6 Gig in Sckipio-Calix Test http://bit.ly/Calix16
A telco tells me they are getting impressive early results from the Calix 48 port DSLAM with the new Sckipio 212 MHz chips. There still is work to do but this is encouraging. 
    Carriers want DSLAMs with more than 16 ports to reduce the deployment costs from the basement or larger field cabinets. Speed matters to the marketing side of the company; AT&T's CEO believes he must offer a true gigabit to match cable. (They've been getting ~750 megabits with first generation chips. http://bit.ly/Calix16

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Reverse Power 4 Port DSLAM for Australia http://bit.ly/NetcommRP
Australia is connecting 1M homes to G.fast, some with a Netcomm distribution point mini-DSLAM. It's a small unit designed for pole or pit mounting. It's waterproof, pressure proof, and temperature resistant. Their matching home modem is bittorrent friendly, with two USB ports for a hard drive dedicated to sharing.
     A reverse power unit at the customer, the NDD-0100-01, can save the cost of bringing power to the DSLAM. They don't expect many orders until the second half of 2018, as nbn is waiting for the second generation chips. Netcomm demonstrated RP with BT Openreach in August. http://bit.ly/NetcommRP

*** Sckipio's Three advances are taking G.fast to the next level.http://bit.ly/Sckipio (ad)

Australia Makes it Official: G.fast to Million Plus http://bit.ly/GFAussie
No news here. In September, 2015, I reported Australia's nbn Going G.fast. This June. I reported the million home fiber to the curb (kerb?) was beginning. Unfortunately, they are no closer to figuring out where to find the needed $10B to $20B to cover the cost overruns. Instead, the parties are battling in Parliament about who is to blame. http://bit.ly/GFAussie

2 Bonded 212 Lines = 3 Gigabitshttp://bit.ly/twobonded
Sckipio at BBWF is demonstrating 3 gigabits down, nearly a gigabit up, over two phone lines, bonded. Twice the bandwidth (212 MHz instead of 106 MHz) times two lines is fast. Sckipio does great demos; at CES, they showed G.fast first generation chips delivering almost 1 gig upstream.
    “Sckipio is pushing Gfast to astonishing speeds with production silicon,” CEO David Baum proclaims. Calix is using the SCK23000 chipset in their 48 port gig+ DSLAM at the show. http://bit.ly/twobonded

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