Light Reading

Docsis 3.1 Targets 10-Gig Downstream

Jeff Baumgartner
LR Cable News Analysis
Jeff Baumgartner
10/18/2012
50%
50%

ORLANDO -- SCTE Cable-Tec Expo -- The Docsis 3.1 platform will support capacities of at least 10Gbit/s downstream and 1Gbit/s upstream, a move that will certainly prolong the industry's need to deploy fiber all the way to the home.

That was one of the big takeaways here Thursday as engineers with CableLabs and some of the nation's biggest cable operators revealed significant details about Docsis 3.1 for the first time. (See Docsis 3.1 to Be Smarter, Faster & Cheaper and Diving Into Docsis 3.1.)

Docsis 3.1 will try to hit some other broad objectives, including cost reductions on a per-bit basis, the development of an effective migration path to the new platform, and assurance that 3.1 will work on existing hybrid fiber/coax (HFC) plant. Thursday's session didn't outline all the apps and services that might require 3.1, but support for much more IP video is certainly going to be among them.

CableLabs expects to complete the core Docsis 3.1 specifications in 2013 and anticipates seeing initial products as early as 2014, according to Matt Schmitt, director of Docsis specifications at CableLabs.

What's in Docsis 3.1?
To hit its capacity targets, the cable industry wants to increase its spectral efficiency by about 50 percent. As expected, the new specs will do away with 6MHz- and 8MHz-wide channel spacing and instead use smaller (20KHz-to-50KHz-wide) orthogonal frequency division multiplexing (OFDM) subcarriers; these can be bonded inside a block spectrum that could end up being about 200MHz wide. (See Docsis 3.1 Will Change Cable's Data Channels.)

OFDM will be matched up with low density parity-check (LDPC), a Forward Error Correction (FEC) scheme that takes up less bandwidth than the current Reed-Solomon approach. LDPC will let cable pump out more bits per hertz by utilizing higher orders of QAM modulation, including 1024 QAM and 4096 QAM in both the downstream and the upstream, Schmitt said. (256 QAM is typically used in today's cable downstream.)

To point out how much more efficient the new approach will be, Schmitt noted that it would take 780MHz of spectrum to get 5 Gbit/s using Docsis 3.0, but only 500MHz with Docsis 3.1.

The hope is that the move to OFDM will also open up the market to more chipset and system vendors and help to reduce costs. The Docsis 3.0 silicon market, for example, is dominated by Broadcom Corp. (Nasdaq: BRCM) and Intel Corp. (Nasdaq: INTC), with STMicroelectronics NV (NYSE: STM) just recently joining the fray. (See STMicro Takes On Broadcom, Intel in Docsis 3.0.)

Migrating to Docsis 3.1
The aim is to make Docsis 3.1 backwards compatible with Docsis 3.0 and 2.0. So, a 3.1 cable modem termination system (CMTS) will be required to support older modems. The first new modems are expected to be 3.1/3.0 hybrids capable of bonding at least 24 downstream channels and eight upstream channels -- essentially what's supported by the Intel Puma6 chip for Docsis 3.0. (See Intel's New Docsis 3.0 Chip Guns for 1-Gig .)

To avoid pricey forklift upgrades, the hope is that the new generation of Converged Cable Access Platform (CCAP) devices will support 3.1 with software upgrades.

Cable has tossed out the idea of doing a "top-split" that would put fresh upstream spectrum above the downstream spectrum, so it will keep things as they are, with the upstream spectrum operating below the upstream. But 3.1 does anticipate a wider upstream (maybe 200MHz or more) that would expand beyond the 5MHz-to-42MHz range used by most U.S. cable systems today.

The specs also consider the notion of expanding the downstream to about 1.2GHz. Most upgraded plant is built out to 750MHz, 860MHz or even 1GHz.

But that's all optional. The key thing is, "you don't have to change your plant to deploy Docsis 3.1," Schmitt said.

The first Docsis 3.1 products to emerge will be CPEs, predicted Jorge Salinger, VP of access architecture at Comcast Corp. (Nasdaq: CMCSA, CMCSK). That would seed the market with 3.1 devices before the network is upgraded. Salinger also expects 3.1 downstream to be ready before its upstream counterpart.

He added that Comcast has begun to think about a second phase of its spectrum reclamation plan that would put space aside for 3.1 that could also help out with the operator's transition to IP video.

Light Reading Cable will have more coverage of Docsis 3.1 developments throughout the week.



— Jeff Baumgartner, Site Editor, Light Reading Cable

(3)  | 
Comment  | 
Print  | 
Newest First  |  Oldest First  |  Threaded View        ADD A COMMENT
comtech3
50%
50%
comtech3,
User Rank: Light Beer
12/5/2012 | 5:18:50 PM
re: Docsis 3.1 Targets 10-Gig Downstream


DOC-3.1 proposal seems to me an overly ambitious prospect that looks good on paper,but in  reality,isn't possible to achieve with the MSOs current plant given that most cable network of amplifiers are rated at 750MHz,and to lower the channel spacing in KHz rather than MHz would be making a great sacrifice of the guard band that would certainly result in interference despite OFM being used. Also, SNR of amplifiers is a factor to consider where there's a disparity between plant amps and in-home amps.


This disparity presents it's self in that most MSOs amp specs requires 45-47db SNR,whereas in-home amps are lower.This anomaly would surely impact customers experience,especially when thermal fluctuations affect signal output.Ingress both in the plant and the home, would also have to be under tight control


I beg the question.Is there a parsity of bandwidth that requires 10Gbps downstream,and1Gbps upstream? Are we talking shared throughput,or individual usage? If the latter is true,then to me that is obsurd because not even most large corporations require that much! And speaking of corporations.Would the various web portals be able to handle the fast influx with their current servers?


 

paolo.franzoi
50%
50%
paolo.franzoi,
User Rank: Light Beer
12/5/2012 | 5:18:49 PM
re: Docsis 3.1 Targets 10-Gig Downstream


comtech3,


So, you think Google does not use 10 Gbps/1 Gbps at HQ?  I think the much bigger issue at speeds like that in a dedicated pipe is the lack of redundancy unless you were going to buy one of those and then a 10GigE from the telco.


seven


 

Jeff Baumgartner
50%
50%
Jeff Baumgartner,
User Rank: Light Beer
12/5/2012 | 5:18:49 PM
re: Docsis 3.1 Targets 10-Gig Downstream


Well, just the timing alone is ambitious. One vendor told me product intros by 2014 would be exactly that.  Also, I believe this would be shared throughput like Docsis is now. JB

Flash Poll
From The Founder
Anshul Sadana answers questions from Steve Saunders, Light Reading's founder and CEO, about Arista's CloudVision, a global cloud network controller for workload orchestration and workflow automation delivering a turnkey solution for cloud networking.
Live Streaming Video
CLOUD / MANAGED SERVICES: Prepping Ethernet for the Cloud
Moderator: Ray LeMaistre Panelists: Jeremy Bye, Leonard Sheahan
Between the CEOs
Video Exclusive With Basil Alwan, Alcatel-Lucent

7|24|15   |   26:44   |   (2) comments


Basil Alwan, President of IP Routing & Transport at Alcatel-Lucent, discusses virtualization, cultural challenges, the capex crunch and more with Light Reading founder and CEO Steve Saunders.
LRTV Custom TV
VDF: Enable the Financial With Mobile Money

7|20|15   |   06:53   |   (0) comments


Ian Ravenscroft discusses how operators can expand to occupy the entire digital services value chain through service innovation.
LRTV Custom TV
Telefónica on OSS Transformation

7|20|15   |   06:01   |   (0) comments


Jose Gonzales discusses the details of Telefónica's operation transformation program.
LRTV Custom TV
Judi Achmadi on Huawei's Cloud Storage Solution

7|20|15   |   03:33   |   (0) comments


Judi discusses the key business goals of TelekomSigma's public cloud service and how Huawei's solution helps them address challenges.
LRTV Custom TV
KPN Enlightening Digital Business & IT Transformation

7|20|15   |   06:19   |   (0) comments


Rob de Beer discusses the changes that operators need to make with service innovation now coming from the Internet world.
LRTV Custom TV
Stratus Telco-Grade Cloud Solutions & NFV

7|20|15   |   07:34   |   (0) comments


Ali Kafel from Stratus Technologies addresses high-availability concerns within the telco industry with a solution that enables telcos to provide high-availability and stateful fault-tolerance using a software-based approach.
LRTV Documentaries
The Six Million Dollar Business Man

7|20|15   |   01:52   |   (0) comments


Steve Saunders, publisher. A man barely alive after an acquisition malfunction imploded the company he founded. Gentlemen, we can rebuild Light Reading. Better, faster, stronger.
Between the CEOs
CEO Chat With Anukool Lakhina, Guavus

7|20|15   |   38:51   |   (1) comment


Guavus CEO Anukool Lakhina talks to Light Reading founder and CEO Steve Saunders about the role of operational analytics in the communications services and networking sectors, particularly in relation to IoT.
LRTV Custom TV
IBM's Flash Storage With Intel QuickAssist

7|20|15   |   03:18   |   (0) comments


Intel's Bev Crair and IBM's Eric Herzog discuss how IBM's V9000 Flash Storage System has helped customers around the world. Featuring real-time compression powered by Intel QuickAssist Technology, the V9000 is a next-gen flash storage solution.
LRTV Huawei Video Resource Center
Thailand's AIS: Transforming to an FMC Operator

7|17|15   |   4:53   |   (0) comments


Saran Phaloprakarn, Senior VP of Fixed Broadband Business Management of Thailand's AIS, was a keynote speaker at the first Asia-Pacific Ultra Broadband Summit in Bangkok. In this video, he talks to Heavy Reading about transforming into an FMC (FBB+MBB+Content) operator.
LRTV Huawei Video Resource Center
Cambodia's TRC Discusses Its Plans for National Broadband

7|17|15   |   10:33   |   (0) comments


In this video, Chakyra Moa, Chairman of Telecommunication Regulator of Cambodia (TRC), talks in in-depth with Heavy Reading about the Cambodia's current telecom market and TRC's goals and expectations for the future.
LRTV Documentaries
5G Phone

7|16|15   |   2:09   |   (4) comments


A man has an opportunity to purchase the world's first working 5G phone. Imagine the possibilities...
Upcoming Live Events
September 16-17, 2015, The Westin Galleria Dallas, Dallas, TX
September 16, 2015, The Westin Galleria Dallas, Dallas, TX
September 16, 2015, The Westin Galleria Dallas, Dallas, TX
September 29-30, 2015, The Westin Grand Müchen, Munich, Germany
October 14-15, 2015, New Orleans Ernest N. Morial Convention Center, New Orleans, LA
November 5, 2015, Hilton Santa Clara, Santa Clara, CA
December 1, 2015, The Westin Times Square, New York City
All Upcoming Live Events
Infographics
Network operators start seeing savings from NFV in the first year, according to a study by Affirmed Networks and ACG.
Hot Topics
T-Mobile Launches RCS Messaging
Sarah Thomas, Editorial Operations Director, 7/22/2015
Huawei Working Hard for Rural Success
Carol Wilson, Editor-at-large, 7/22/2015
AT&T U-verse TV Hits the Skids
Alan Breznick, Cable/Video Practice Leader, 7/24/2015
Eurobites: Alcatel-Lucent, Vodafone Test TWDM-PON
Paul Rainford, Assistant Editor, Europe, 7/22/2015
RJio to Launch Its Own 4G Devices Brand
Gagandeep Kaur, Contributing Editor, 7/27/2015
Like Us on Facebook
Twitter Feed
Webinar Archive
BETWEEN THE CEOs - Executive Interviews
Basil Alwan, President of IP Routing & Transport at Alcatel-Lucent, discusses virtualization, cultural challenges, the capex crunch and more with Light Reading founder and CEO Steve Saunders.
Guavus CEO Anukool Lakhina talks to Light Reading founder and CEO Steve Saunders about the role of operational analytics in the communications services and networking sectors, particularly in relation to IoT.
Cats with Phones
Cat Sense Click Here
Can you hear me now?