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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

G.Fast performance per AlcatelG.Fast speeds. Larger version below  Update 7/13 I've since learned the BT target speed is 250 megabits because they don't intend to deploy enough fiber for higher speeds. From January: If a 4,000 home summer trial goes well, 3/4ths of the country will covered over a decade.  Gavin Patterson's plan goes far beyond anything even rumored in any other country. Trevor Linney and BT were among the first testing At that time they were part of the gigabit hype. Patterson's announcement this time is far more realistic, speaking of "hundreds of megabits" for now. In fact, BT's talk of 400 metres suggests they are looking at one of the Midi-DSL versions rather than today's

  • "speeds of a few hundred megabits per second to millions of homes and businesses by 2020. Speeds will then increase to around 500 Mbps as further industry standards are secured and new kit is developed." 

A few hundred megabits is closer to the current state of the art, especially if you measure download speeds. It's realistic to expect improvements to over time.  The current designs only use 106 MHz but the standard allows up to 212 MHz. Alcatel and other engineers are confident that non-linear precoding will be a major improvement but non-linear wasn't ready for the current version of the standard. I believe the noise-cancellation (vectoring) in the earlier chips will have room for improvement.

Huawei supplied the gear for the earlier BT testing, Their HiSilicon subsidiary is working on a chip but I don't know if it's ready. If HiSilicon isn't available, both Sckipio and Broadcom are promising chips for trials in the summer. 


G.Fast performance per Alcatel
Particularly interesting is BT's comment

  • During the trials we will be testing new ‘micro cabinets’ that are about the size of a biscuit tin and can be attached to telegraph poles, walls of buildings or placed in footway boxes. Max range 400m, possibly further. 

Attributed to a BT spokesman by Techcrunch. At 400 metres, today's version would top out below 50 megabits. Midi-DSL sacrifices speeds over 500 megabits in return for better performance, perhaps 200 megabits, at distances of 300-400 metres. Adtran, Alcatel and Huawei have proposed versions of Midi-DSL but none are close to market. It's much cheaper to locate cabinets at 300-400 meters. BT hopes many of the existing cabinets can be repurposed. 

200 megabits sounds good to me.

Here's the announcement 


DC15-035                                                         30 January 2015 

BT CEO sets out ultrafast broadband vision

“” to deliver speeds of up to 500Mbps to most homes 
Premium fibre services of up to 1Gbps to be developed 

BT CEO Gavin Patterson today set out the company’s ambition to transform the UK broadband landscape from superfast to ultrafast. 

He revealed that BT plans to deliver much faster broadband for homes and small businesses via a widespread deployment of “”. This is an innovative technology that BT will test in two pilot locations starting this Summer. will help BT deliver ultrafast speeds of up to 500Mbps to most of the UK within a decade. Deployment will start in 2016/17, subject to the pilots being successful. 

Early tests show is capable of delivering a range of speeds depending on how close the technology is to a customer’s premises. BT expects to offer initial speeds of a few hundred megabits per second to millions of homes and businesses by 2020. Speeds will then increase to around 500Mbps as further industry standards are secured and new kit is developed. 

“BT is a world leader when it comes to fibre innovation and we are excited about the next stage in our story,” Patterson said today. “We believe is the key to unlocking ultrafast speeds and we are prepared to upgrade large parts of our network should the pilots prove successful. That upgrade will depend however on there continuing to be a stable regulatory environment that supports investment. 

“The UK is ahead of its major European neighbours when it comes to broadband and we need to stay ahead as customer demands evolve. will allow us to do that by building on the investment we have made in fibre to date. It will transform the UK broadband landscape from superfast to ultrafast in the quickest possible timeframe.” 

The two pilots will start this Summer in Huntingdon, Cambridgeshire and Gosforth, Newcastle. Around 4,000 homes and businesses will be able to participate in the pilots which will explore what speeds can be delivered using at scale. 

The pilots will build on recent tests at BT’s world renowned innovation centre at Adastral Park, Suffolk. These have shown that has the potential to deliver significant speed increases from existing and new fibre street cabinets as well as from other points closer to the customer. This is an important development as it means the technology can be deployed in a more efficient and rapid manner than previously thought. 

BT is likely to deploy from various points in the network, with the pilots allowing it to assess various roll out options. It is also planning to develop a premium fibre broadband service for those residential and business customers who want even faster broadband, of up to 1Gbps. 

BT is currently expanding the reach of its fibre network by working with the public sector across the UK. Its network already passes almost 22 million premises – around three quarters of the UK – and is open to all communications providers on an equal basis. Its expansion will help the UK to boast 95 per cent coverage for fibre broadband within the next few years. 

The UK is already ahead of Germany, France, Italy and Spain when it comes to superfast broadband coverage and take-up 1 , and BT’s plans will ensure the UK stays ahead and joins the ranks of world leaders such as Japan and South Korea. 

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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