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Gfast map July 2017

Dark blue: 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

Light blue: Smaller carriers in Germany, Norway, Finland, Japan

Green: Incumbent likely:  France, Germany, & Poland  

British-Telecom-noise-dataAT&T leading the efforts for an updated standard. Field tests of current G.fast gear have seen speeds of 400-700 megabits downstream, not the gigabit promised in early pr. 400-700 is plenty for almost everyone but the marketing department is worried. Cable is going to one and two gig (shared.) Google is just one of hundreds around the world offering a symmetric gig. The engineers have marching orders: get our G.fast speeds to a true gigabit ASAP!

Fortunately, the engineers are confident they can reach a gigabit.The ITU group already is working on a second appendix to the G.fast standard, aiming for 2016. A chip CTO tells me it will be easy to do more efficient coding (non-linear precoding) and transmit more bits for a given frequency (constellation.) Those two changes he believes enough to do the trick. 

Trevor Linney of BT is running the most advanced tests of G.fast, connecting 4,000 homes. He reports "Our research shows that even more capacity can come from copper."

He also predicts more bits per tone and a lower noise floor (i.e. <-150dBm/Hz). He supports that with the test data in the illustration.  Increasing the transmit power, perhaps to 8dBm, is also under consideration. 

ITU-T agreed to specify non-linear pre-coding in an amendment to G.9701. Dong Wei of Huawei presented the data below at the excellent Upperside Conference. Interference is different at different frequencies a better coding scheme can make a large difference. Simulations show a difference of 100-300 megabits. Wei presented three different possible coding schemes, the three upper lines in the graph. Deciding on which is right for the standard can be challenging, one reason standards take time to develop. 

Bonding two lines doubles the speed, also new to the standard.

Non-Linear Precoding Huawei

 

 

 

ITU-T agreed to specify non-linear pre-coding in an amendment to G.9701. 

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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