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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  

Cavium OCTEONToday's fronthaul CPRI usually requires 2.4Gb/s to 7.2Gb/s, too much for Today's wireless network often has a single Baseband Unit (BBU) supporting multiple Radio Units (RU), also called remote radio heads. Cellular speeds are just now rising from 100-150 megabits to 300-450 megabits, well within the capacity of My initial reaction was "ho-hum," but BT's Richard Knowles pointed out what I had missed. Most fronthaul uses the Common Public Radio Interface, which requires much higher speeds. BT and Cavium found an alternative that brought fronthaul requirements down to speeds.

 They may be spread across a building for better indoor coverage or may be kilometers away. The connection from a BBU in the field to the remotes is called "fronthaul." Backhaul is from BBU to the high capacity of the telco network. CPRI fronthaul speeds require fiber today. 

Cavium and BT are developing an alternative to CPRI that requires less bandwidth.

Knowles writes, "By splitting the base station functionality above the physical layer we have successfully demonstrated a ‘Mid-haul’ solution which requires 10% overhead above the line rate. Using CPRI, the front haul would require 2.4Gb/s to support 150Mb/s,  using the novel functional split this is reduced to 170Mb/s. Angel Atondo of Cavium explains what they are testing. "This trial splits the LTE L1-L2 protocol and significantly reduces the required fronthaul bandwidth."

There could be large savings in some locations up to 400 meters with copper available. 150 megabits won't be sufficient for long in many places because LTE is quickly moving to two and three carriers and higher order MIMO. Data rates of 300-800 megabits will become common.

Cavium and BT hope will bring down the effective cost of small cells, especially 5G in high frequencies. Five years ago, most of us expected substantial deployments of small cells and femtocells. It hasn't happened and some once very promising companies are no longer with us. The backhaul costs were just too high. Sometimes, real estate was also prohibitive. "The lab based demonstration showed successful operation of this concept over, a major milestone in our research," BT writes.

Here's the pr.

BT partners with Cavium in Cloud RAN trials

BT announced today that it has successfully used technology to deliver a ‘Cloud Radio Access Network’ (C-RAN) cellular network service over copper, in an experiment believed to be a world first.

C-RAN is a new network architecture used to connect cellular base-stations to mobile operators’ core networks. A traditional approach to C-RAN requires a dedicated fibre link to connect transmitters at the top of a cell tower to complex signal-processing equipment deeper in the network. This can involve complex and costly engineering work if no fibre is present in the ground to carry the signal.

Researchers at BT’s Adastral Park Labs in Ipswich, in collaboration with US-based semiconductor manufacturer Cavium, Inc. (NASDAQ: CAVM), have demonstrated that they can use technology to deliver cellular data over copper lines at speeds of 150 – 200Mbps. 

This removes the need for mobile operators to invest in costly, high capacity backhaul links over dedicated fibre connections.  By providing a far more economic “fronthaul” connection between the base station and the mobile operators’ core network, a C-RAN service delivered over would significantly lower the cost of deployment for mobile operators building out 4G networks today and 5G architectures in the future.

Dr Tim Whitley, MD for Research & Innovation at BT said: “Using to deliver a cellular network is an exciting breakthrough for C-RAN and yet another world first for our team of researchers at Adastral Park.

“These technologies will play a key role in 4G networks and will be fundamental to 5G architectures. The trials are another step towards a fixed and mobile network which will support customers’ increasing demands for data.”

“We are very excited to collaborate with BT, using Cavium OCTEON Fusion-M™ basestation and ThunderX® server processor technology to validate this new class of Radio Access application with technology.” said Raj Singh, General Manager of Cavium’s Wireless Broadband Group. 

“Our successful testing has laid the groundwork for enabling LTE deployments today and 5G deployments in the future using”

As well as exploring the role that may play in helping operators to roll out their 4G/5G networks, Openreach, BT’s local access network division, is also trialling as an access technology in Huntingdon and Gosforth, alongside a further BT technical trial in Swansea. is significant because by building on current Fibre-to-the-Cabinet (FTTC) technology, it allows Openreach to bring ultrafast speeds to a wide footprint far more rapidly and without the expense and disruption of running fibre directly into a home or business. 

If the trials prove successful – and if UK regulation continues to encourage investment – the company has pledged to provide ultrafast speeds to 10m homes by 2020 and to the majority of the UK within a decade. 
BT has invested c£500 million that in R&D every year. The company is one of the largest investors in R&D of any company in the UK and globally in the telecoms sector, and currently holds an astonishing 4,560 patents. 



FrontHaul for indoor coverage

Indoor spaces isolated from macrocell coverage may have peak traffic at different times than those that occur outdoors, especially weekends and evenings. Examples of such areas are usually indoor stadiums, shopping centers, cafés/bars, convention centers, and government offices, covered by indoor lampsites, hotel BBUs, etc. Indoor small cells placed on ceilings or interior walls can use existing FTTx or Ethernet resources as per the availability.

However, wired solutions can play a useful role in small cell backhaul, and of course, the overall backhaul solution can be a hybrid of wired and wireless (such as short-length microwave connectivity).

FrontHaul for outdoor coverage

For outdoor FrontHaul coverage areas, microwave technologies, including E-Band (71 to 76GHz), V-Band (60GHz), and Sub Link (Sub 6GHz) are usually best for supporting the LOS/n-LOS/N-LOS terrains. This accelerates rollout and makes O&M quite a bit easier, while enabling full outdoor assembly and unified NMS solution. It is more adaptable in terms of site location (walls, rooftops, poles, etc.). PMP application is useful as it eliminates the need for line-of-sight, making it useful for hotspot areas, while PTP application, with its longer transmission distance (though line-of-sight) can connect PMP hub modules with macro sites.

BT's Richard Knowles 

The Site for gfast 230 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
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 Soukup told BBWF, "We're going to have a field test in Frankfurt with 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. 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.

*** 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 (ad) It is the best technical guide to  I have seen. Grab it. Dave

1.6 Gig in Sckipio-Calix Test
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.

*** Self-Healing Wi-Fi With ASSIA Real-Q 
Beyond-the-Box visibility and control extends quality-of-experience (QoE) beyond the gateway to the end-user device for every device in the home. Based on ASSIA technology, proven across 80 million subscribers (ad)

Reverse Power 4 Port DSLAM for Australia
Australia is connecting 1M homes to, 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.

*** Sckipio's Three advances are taking to the next level. (ad)

Australia Makes it Official: to Million Plus
No news here. In September, 2015, I reported Australia's nbn Going 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.

2 Bonded 212 Lines = 3 Gigabits
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 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.

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