Sorting Out Cable's Gigabit Strategy

Although the Gigabit Era has clearly begun, most cable operators are still trying to figure out the best way to compete successfully with their fiber-based rivals. As a result, they are likely to introduce gigabit-enabling technologies such as DOCSIS 3.1 and CCAP on an incremental basis over the next few years, rather than roll them out all at once.

So while we've seen headline-grabbing D3.1 rollout plans already announced by such giant US and international MSOs as Comcast Corp.(Nasdaq: CMCSA, CMCSK) and Liberty Global Inc. (Nasdaq: LBTY) and a few smaller ones like Atlantic Broadband and General Communication Inc. (GCI)(Nasdaq: GNCMA), much of the change will be more gradual.

That much was clear at the SCTE Cable-Tec Expo show in New Orleans two weeks ago. Teams of MSO technologists trooped from booth to booth on the crowded exhibit floor, seeking to find the right combination of equipment and software to start offering gigabit speeds as soon as comfortably possible. Engineers kicked the tires on new cable modems, wireless gateways, cable modem termination systems (CMTSs), Converged Cable Access Platform (CCAP) devices, testing products and more, hoping to come up with the magic formula.

Naturally, the vendors were more than happy to accommodate the MSO engineers, serving up plenty of DOCSIS 3.1 (D3.1) and CCAP gear to entice the operators. Major equipment suppliers like Arris Group Inc. (Nasdaq: ARRS) and Hitron Technologies Inc. showed off brand new D3.1 modems, while such other prominent players as Casa Systems Inc. , Cisco Systems Inc. (Nasdaq: CSCO), Gainspeed and Huawei Technologies Co. Ltd. demonstrated their versions of either integrated or distributed CCAP systems with D3.1 capabilities. (See Hitron Demos DOCSIS 3.1 Cable Modem at SCTE 2015 and Progress of DOCSIS 3.1 in the Cable Industry.)

For instance, Huawei's large "Gigaband Network" booth featured displays of a range of D3.1-enabling equipment, including the vendor's new 3.1 modem and its distributed CCAP solution, known as D-CCAP. Like the other major vendors, Huawei is now seeking certification of its modem and qualification of its D-CCAP system by CableLabs , which began formal testing of D3.1-related gear in late August. Similar to its rivals, Huawei is also seeking to sign up North American, European and Asian cable operators for field trials and pilot deployments of its D3.1 equipment over the next year. (See Ericsson Buys Cloud Video Firm for $95M.)

While few, if any, firm equipment purchase decisions were likely made at the show, an industry consensus for rolling out both D3.1 and CCAP seems to be emerging. It looks like most cable operators will introduce both gigabit-enabling technologies on an incremental, system-by-system basis over the next few years, just as they have done before with other nex-gen technologies. (See Clock Starts on DOCSIS 3.1.)

In an informal poll conducted during a BTR morning panel on D3.1, for instance, most operators in the room indicated that they do not intend to follow the bold examples of Comcast and Liberty Global and launch D3.1 across their regions next year. Instead, most said they wouldn't begin D3.1 rollouts until 2017 or possibly even later. So don't expect DOCSIS 3.0, or even DOCSIS 2.0, to disappear from the cable landscape any time soon.

Reflecting this careful, incremental approach, the first wave of D3.1 modems coming off the assembly line for testing and approval by CableLabs are hybrid models capable of supporting both the D3.1 and D3.0 specs. Specifically, the new, pricier modems will support both the bonding of 32 downstream and eight upstream channels under the D3.0 spec, as well as the use of subcarrier blocs based on orthogonal frequency-division multiplexing (OFDM) technology under the new D3.1 spec. "DOCSIS 3.1 modems will operate like the best DOCSIS 3.0 modems you can buy," said Jorge Salinger, VP of Access Network Architecture at Comcast, speaking on the BTR panel.

As cable providers begin introducing D3.1, they will roll out CCAP along with it to support the surging bandwidth demands of gigabit services, IP video, Ultra HD video, WiFi, business services and other popular offerings. The only question is which type of CCAP architecture they will choose. As a result, the debate is already heating up over the various versions of CCAP available, including the already established integrated CCAP chassis and several new remote or D-CCAP architectures, such as the D-CCAP approach promoted by Huawei.

We'll have much more to say about CCAP, particularly D-CCAP, in our next post in this series. But for now suffice it to say that, as cable operators grapple with their gigabit plans, the various flavors of CCAP will undoubtedly play a large role in that discussion.

— Alan Breznick, Cable/Video Practice Leader, Light Reading

This blog is sponsored by Huawei.

LuisBlanco 10/27/2015 | 3:30:20 PM
G.Fast over Coax for MDUS, Cheaper? Better? Thanks Daniel for your comment. I completely agreed. I do not think FTTH from Telcos is the competitor to DOCSIS 3.1 or Gigabit access. They are going to deploy G.Fast first, specially for browfield and MDUs. FTTH for browfield MDUS is too expensive for Telcos just the same as for MSOs.

G.fast gives you around 1 Gbps within 50-100 meters from DPU (GPON ONT) to GPON CPE at the customer premessis. They called it FTTdp. Fiber to the distribution point. 

Some clarifications on G.fast:

1) It does not have to be backwards compatible to xVDSL. Telcos do not want that they want a totally new technocloyg G.fast (even XG.fast tested with BT last week % Gbps).

2) G.fast speeds are symetrical, but, to my knowldedge DCOSIS 3.1 is not. Thats a major advantage if everyone is uploading youtube and using p2p video to see sports, etc. 1 Gbps upstream may not be needed now, but surely the perception (and marketing from Telecos) is that their upstream speeds (G.Fast) are way better than DOCSIS 3.1.

3) Timelines, G.Fast standards (final approval 2013) and deployments are 2 years ahead of DOCSIS 3.1. Deployments (and all the expected marketing around the bidirectional Gibabit access network) start next year. Chipset available, Trials have been going for a while.

4) It is GPON (for Telcos, for MSOs can be 10GE) to the basemen of the MDU. Where is the DPU/ Similar to the distributed R-CMTS/C-DOSIS idea, but no Docsis in the other side, in this case is G.Fast a total new technology even for telcos. Doing Fibert to MDU using digital fiber (no analog to FN) has the advantage of being well position for the future, could be a long future, do FTTH.

5) G.fast basically uses OFDM over 100 MHz channels. The next step is 200 MHz by bonding 2 channels of 100 MHz. 

By doing G.Fast over Coax, instead of twisted pair, there is less near/far noise. So even Telecos are considering used the Coax access (which is owned by the MDU owner, not the MSOs). We all know that COAX is better than Twister pair.

I think some MSOs should be a comprehensive anaylysis for browfield MDUS on the cost of doing G.Fast over Coax, instead of DOCSIS 3.1 from FN. We are assuming in both cases that there is fiber to the MDU (analog or Digital), so that cost is the same. Of course for MSOS additional cost has to be added to learn a new technology and back office integration. For telcos it is a new technology (nothing to do with xVDL). Maybe the IT integration is easier for telcos (same as they have now, just a new technology) than for MSOs to replace DOCSIS provisioning. All those factors need to be taking into consideration (not just the cost of the equipment,etc). On the other hand, for DOCSIS 3.1 the cost of upgrading the HFC to support DOCSIS 3.1 (specially for the company that have 750/850 MHz plans), could be significant too. So another factor to take into consideration.

The good news, if it works for Telcos (the G.fast over Coax), nothing stops the MSOs to do the same.

My two cents of this..
danielcawrey 10/26/2015 | 8:42:42 PM
New Options Gigabit is going to become immensely important in the future, and cable companies know it. 

Think about all the streaming that's going on now. Customer expect to be able to get media from multiple on-demand sources. Things like gaming and virtual reality are also going to cause pretty serious demand as well. Cable companies need to stay on top of this reality. 
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