In case you haven't heard by now, Comcast has embarked on an ambitious quest to upgrade by 2025 its entire broadband network into a symmetrical multi-gigabit-per-second "10G" transom, powered by Full Duplex (FDX) DOCSIS 4.0 technology, and delivered over a virtualized distributed access architecture (DAA) scheme using virtual cable modem termination system (vCMTS). 

But wait, there's more. 

Showing off the range of ways it can deliver fast internet using this new network tech, Comcast on Thursday published a blog from its Chief Network Officer, Elad Nafshi, who described a customer trial conducted by the cable company in Denver late last year in which fiber-to-the-premises (FTTP) was delivered using a new method. 

Leveraging the DAA and vCMTS capabilities of Comcast's new network, targeted FTTP was delivered using a virtual broadband network gateway (vBNG) and a remote optical line terminal (rOLT) plugged into the node.

"Traditionally, fiber and coaxial networks have relied on different platforms to service customers -- each with its own separate technologies, customer solutions and speeds — but this is changing," Nafshi wrote.

The technology differs from Comcast's existing  -- and pricy -- "Gigabit Pro" FTTH service, which delivers symmetrical 6 Gbps speeds. 

Nafshi didn't specify any kind of timeline as to when Comcast's new vBNG/rOLT tech might actually be deployed. 

Describing potential use cases, Nafshi added that Comcast's new 10G network "affords unprecedented optionality, which empowers us to deploy the right network for the right location at the right economics as we continue to expand our network to more homes. For many customers, this means leveraging the connections already in place in their homes, which are typically coax. For others, like those in untapped rural areas or newly built multifamily buildings, it might mean fiber. We can make the best decision for our customers’ needs when it comes to how we deliver connectivity in the most efficient, cost-effective and timely manner possible."

The cable broadband technology business is a competitive sector right now, with incumbents like CommScope trying to hold off insurgents including Harmonic as cable operators upgrade and virtualize their networks for the ”10G“ future. 

Harmonic, which received a $175 million commitment from Comcast three years ago, with the No. 1 U.S. cable operator developing its future network virtualization framework around Harmonic’s Distributed Access Architecture (DAA) technology, believes it's on the cusp of yet another huge customer victory. 

“There’s a growing industry consensus that the particular variant of DAA we pioneered with Comcast and other early customers that its virtualized CMTS paired with remote PHY nodes is the most architecturally advantageous and market-proven solution and consequently, the best way to go,” Harmonic president and CEO Patrick Harshman said during the company’s third-quarter earnings call Monday. 

Light Reading reported last week that Charter Communications is now following the same DAA recipe of virtualized cable modem termination system (vCMTS) paired with remote PHY (R-PHY). 

Harshman was careful Monday to add that the “growing consensus” he mentioned several times ”isn’t complete.” 

Also last week, for instance, the biggest cable tech vendor, CommScope, revealed that the No. 5 U.S. cable operator, Mediacom Communications, had signed on to use the tech company's "MACPHY" DAA solution — a technology that also extends MAC (media access control) processing to the outer node-level edges of the network, in addition to CMTS functions. 

“We are prepared and capable of supporting MACPHY,” Harshman noted. 

Cable operators are replacing bulky, expensive proprietary network hardware with virtualized solutions such as Harmonic’s CableOS, which runs on commodity-level computer servers. It’s a step to a broader agenda referred to in cable industry marketing-speak as 10G — symmetrical downstream and upstream delivery of multi-gigabit speeds using the next generation of the industry's core-level DOCSIS technology, DOCSIS 4.0. 

And right now, the vendor market is heated. 

“It’s just becoming a much more competitive market for traditional cable operators,” Harshman said. “I think some of them are deciding that the time to evaluate different technology alternatives is over and the time to begin planning to get on with it is at hand.”

Of course, on Wall Street, the narrative of a tech company on the cusp of possibly controlling the future of American wireline broadband only carries so much clout. 

For the third quarter, Harmonic beat forecasts on revenue with a 23.3% year-over-year sales uptick to $155.7 million. Still, revenue from its video segment was down, and the company’s stock price had cratered more than 10% in late-morning trading Tuesday. ■

CommScope has announced a key customer win as it tries to maintain its position as the top cable technology vendor amid the cable industry’s “10G” network tech transition.

Hickory, North Carolina-based CommScope will be the primary tech vendor for the nation’s fifth-largest cable operator, Mediacom Communications, as it transitions its network to a virtualized Distributed Access Architecture (DAA) configuration.

In engineering-speak, CommScope will supply Blooming Grove, New York-based Mediacom, which serves around 1.47 million broadband customers, with its RD2322 RxD, “operating as a Remote MACPHY Device in the OM4120 Optical Node, configured with a high-split (204 MHz) upstream.”

CommScope and Mediacom have already collaborated on a successful trial in Ames, Iowa, of the vendor’s Remote PHY solutions, which featured CommScope products including the E6000 Converged Cable Access Platform (CCAP) Core, OM6000 node, Remote PHY Device (RPD) and Video Unified Edge (VUE).

The top cable operators, including Comcast and Charter Communications, have already begun the process of upgrading their 1 gigabit-per-second-capable DOCSIS 3.1 networks to the new Full Duplex DOCSIS 4.0 standard, which will provide symmetrical multi-Gbps speeds both upstream and downstream. 

Simultaneously, they’re virtualizing expensive, power-intensive proprietary cable-network hardware, migrating these devices’ functions to software running on commodity x86 servers, under the catchall heading DAA. (The cable industry has thrown both FDX DOCSIS 4.0 and DAA into an even broader bucket it calls 10G.)

Insurgent vendors including Harmonic have targeted CommScope's dominant market share in cable tech with new DAA software solutions. But the Mediacom win seems to show that CommScope is at least holding its own. Neither CommScope nor Mediacom disclosed how much money is involved in the commitment. 

“CommScope’s flexible solutions have allowed us to take advantage of our installed base of nodes, as well as the RD2322 RxD's ability to operate as a Remote MACPHY device, to make a smooth and efficient transition to our network of the future,” Mediacom chief technology officer JR Walden said in a statement. 

Added Guy Sucharczuk, senior VP and general manager of Access Network Solutions for CommScope, “This is a significant step forward for Mediacom's network, and it's a showcase for how CommScope is equipping the world’s leading operators for the 10G future.” ■

During the recent public health emergency, broadband established itself as the runtime of the world (or at least the world that has access to it). Now, as we start returning to some semblance of normalcy, the role of broadband in powering the massive digital acceleration that is underway is coming into sharper focus. This is particularly true in the residential market, where the cable industry is a major connectivity provider in many parts of the world. Not only existing services such as video streaming and gaming grew, but the home became the point of delivery of new services, some of them mission critical, such as age in place, remote patient monitoring, and even home hospital. 

This new reality is energizing the cable industry, as was clear in the recent SCTE Cable-Tec Expo virtual event. Although the conference had to be delivered over — what else — broadband, the vitality was palpable and it is clear the cable industry is gearing up to meet market demands. A few highlights worth noting:

• Upstream: Although bandwidth consumption continues to grow, upstream consumption is increasing even more quickly, which is causing operators to allocate more spectrum to upstream, either via mid-split or high-split of the spectrum. To that end, some operators are turning on existing but largely unused DOCSIS 3.1 capabilities such as orthogonal frequency-division multiple access (OFDMA), and exploring other measures. 

• Multi-Access Edge Computing (MEC): Some technologies (for example, augmented reality) and applications (for example, home healthcare) are driving the need for compute resources in the access network. Operators are beginning to locate compute resources in their headends and hubs, particularly as space is alleviated with the introduction of distributed access architectures (DAAs).

• DOCSIS 4.0: Published by CableLabs in March 2020, this spec is generally viewed as the stepping stone toward 10G. It supports two alternatives: Extended Spectrum DOCSIS, generally requiring augmenting the spectrum to 1.8 GHz, and Full Duplex DOCSIS, which can operate within the 1.2 GHz spectrum but requires either N+0, or N+X, X being a special type of amplifier. Although DOCSIS 4.0 won’t see the field for some time, major operators have announced successful lab trials of both approaches.

• Low Latency DOCSIS: for latency intolerant applications such as gaming and wireless backhaul.

• Distributed Access Architecture (DAA): The subject of much debate, planning and limited deployments to date, DAAs gain momentum, largely for two reasons:

> The traditional methods for adding capacity in the access network are running their course. Capacity has been typically added via node splits or by augmenting the spectrum. Node splits require more equipment (and power consumption) in the headends and hubs. 

> Flex MAC Architecture (FMA) is becoming a reality. For some time, operators had to make an upfront decision regarding where to place the Media Access Controller (MAC) function in a DAA configuration, namely whether to consider a Remote PHY or a Remote MACPHY configuration. Among its many capabilities, the FMA provides operators with flexibility as to where to locate the MAC. CommScope is seeing significant traction for FMA, and Harmonic announced an FMA solution just before Cable-Tec Expo.

• Passive Optical Networking: This technology is growing in importance for the industry, driven by the massive need for capacity and the increasing focus on bringing broadband to currently underserved markets, such as rural areas. 

• Predictive Network Management: As more critical applications are delivered over broadband networks and as operators strive to deliver a superior customer experience, data analytics and machine learning are enabling more sophisticated capabilities for predicting and remediating failures before they escalate into network outages.

• Next-Gen Network Management: With network disaggregation (particularly with DAAs), network management becomes exponentially more complex and requires state-of-the-art tools with automation and increasingly less human dependence.

These are just a few of the highlights of SCTE. To discuss this important industry event engage with me on Twitter at @offredo.

The year that was…

2020 was a year like no other. The pandemic drove an unprecedented acceleration of digital enablement, as companies and organizations of all types adopted virtual substitutions to in-person experiences, such as remote work, online education, and telehealth. This drove a massive consumption of bandwidth, upstream and downstream, and led cable operators to add 1.32 million subscribers in 3Q 2020 alone.

Broadband service providers have added capacity at a furious rate in 2020 to meet the exploding demand. Due to the short-term circumstances, some broadband providers, and more specifically cable operators, had to temporarily put aside their longer-term plans, such as virtualization and the re-architecture of the access network, and use more traditional tools to add capacity. 

The massive need for capacity in the upstream has prompted operators to reconsider tools they had in their arsenal, such as mid-split, which allocates 85 MHz of spectrum to upstream, and high-split, which allocates up to 204 MHz but may require the spectrum to be extended to 1.2 GHz to preserve downstream capacity. Another technology that received renewed attention in 2020 is orthogonal frequency division multiple access, which is part of the DOCSIS 3.1 specifications and improves spectral efficiencies, resulting in added capacity.

The year ahead

High levels of bandwidth consumptions will continue

Although the level of growth will taper off in 2021, high levels of bandwidth consumption will continue in 2021 as some of the digitally enabled business models will persist and evolve to become an essential part of the strategic framework. For example, many companies will retain some version of flexible work arrangements well beyond the pandemic, and some predict that about 20% of remote work will never return to in-person; another example is healthcare where the limits on in-person treatment drove almost a five-fold increase in telehealth-based treatment. Healthcare regulation is expected to continue to be relaxed in 2021, and telehealth utilization is expected to persist, and indeed grow, as the industry evolves business models toward more comprehensive virtual care modalities that include solutions such as remote patient monitoring and age in place. In addition to driving bandwidth consumption, these solutions will over time accelerate the comprehensive re-planning of the communications and computing infrastructures.

Technologies that gain traction in 2021

Mid-split and high-split: The trend that started in 2020 will continue, as the need for capacity in the upstream will exceed the capacity of most existing cable access infrastructures.

Low latency DOCSIS: More and more applications, such as gaming, are demanding latency as low as 5–10ms. New applications are emerging where continuous remote health monitoring of patients in their homes complemented by real-time remote data analytics that inform medical treatment may also require low latency data in the near future. Furthermore, augmented reality and virtual reality (VR) applications are increasingly finding important applications in medicine. For example, at Cedars-Sinai hospital in Beverly Hills, California, a study is focused on using VR for a nondrug approach to treating lower back pain.

The Distributed Access Architecture (DAA): DAA took a relative backseat in 2020 as operators used largely proven methodologies to meet capacity demands. However, continuing to add capacity with node splits and more hardware in the headends is not sustainable over the long term. Therefore, DAA remains the most viable architecture over the long term, with fiber moving ever closer to the customer. The debate between Remote-PHY and Remote MACPHY seems to have subsided somewhat, and the recently introduced Flexible MAC architecture, which gives operators flexibility in the location of the MAC, is gaining industry traction. 

Virtualization and cloud native implementations: As operators raced to meet the capacity surge, a clear shortcoming they faced is their inability to elastically scale capacity with demand. If the level of demand does not sustain at the level for which they planned, some of the capacity added will not be utilized, resulting in stranded capital. One of the main advantages of virtualization is the velocity and flexibility that operators gain in introducing new services and features, in scaling capacity with demand, and in gaining more visibility into their networks, leading to fault mitigation and better reliability. The move toward a virtualized headend, already under way, will continue and even gain momentum as the operators exit fire-fighting mode. 

DOCSIS 4.0: As demand for upstream bandwidth continues to grow, operators will need capacity beyond mid-split and even high-split. The DOCSIS 4.0 specifications, released in early 2020, enable operators to increase upstream capacity to 6 Gb/s. Although field implementations are still years out, operators will begin to decide their DOCSIS 4.0 strategy. Operators have two approaches to consider: Extended Spectrum DOCSIS, which involves increasing the highest plant frequency from 1.2 GHz to 1.8 GHz and later to 3.0 GHz; and Full Duplex DOCSIS, which works within 1.2 GHz using overlapping frequencies for upstream and downstream but may impose restrictions on the number of amplifiers and other legacy equipment between the node and the subscriber.

Passive Optical Networks (PON): Another approach that operators are considering for achieving 10G capacity is FTTx implementations via PON solutions, which allows them to build on their HFC investments to deliver even higher speeds. 

WiFi 6 and 6E: The need for more capacity and performance will continue to drive deployments of WiFi 6, and as WiFi 6E is introduced in 2021, which delivers even more capacity, operators will start supporting the new technology.

Automation: The recent pandemic, social distancing requirements, the increasing complexity of the networks, for example DAA deployments and 5G backhaul densification, will drive operators to implement more automation in the networks.

New business models will be explored

As bandwidth consumption shifts to homes and other locations, and as bandwidth is increasingly used to replace in-person activities, new frameworks around who pays for broadband will start to be explored, as discussed in a prior blog.

Beyond broadband networks

Although the focus has been on bandwidth capacity, and justifiably so, major currents are underway in the broader telecom industry. As digital enablement accelerates, companies in many verticals and consumers in their homes will need increasingly complex applications. Delivering connectivity, while essential, will no longer be sufficient. Offering complex solutions that include connectivity, computation, automation, and generic and vertical-specific application modules will emerge; service providers have the opportunity to play a major role in this emerging area. However, this will require investments, new partnerships, and innovative business models.

Guest blog author Liliane Offredo-Zreik is a principal analyst at ACG Research, where she is responsible for cable access infrastructure market research and consulting practice. Offered-Zreik is also president and founder of boutique advisory firm The Sannine Group.

The migration of hybrid fiber-coax networks to broadly virtualized design with Distributed Access Architecture (DAA) was a technology theme at last year’s SCTE-ISBE Cable-Tec Expo in New Orleans.

Twelve months later, nine of those spent in the triage setting of a pandemic, the Society of Cable Telecommunications Engineers is hosting a virtualized version of its signature Expo event (unfurling Oct. 12-15 on a computer monitor near you). And cable technology vendors are experiencing their own kind of pandemic-related Groundhog Day, with their operator clients sidetracked from new tech to focus on the short-term, emergency issues of network capacity expansion to serve customers working their jobs and attending school from home.

That heavenly “10G” future everyone was dreaming about in 2019? Well, that just had to wait. 

“Deployment of virtualized technology did slow down over the last nine months,” conceded Kevin Keefe, senior VP and segment leader of broadband networks for CommScope. “To say that everyone put things on hold is maybe too strong. But operators did shift their focus to the here and now, trying to get as much bandwidth as they could really quickly. The focus has been on bandwidth, bandwidth, bandwidth.”

Node splits and network frequency increases have enabled operators in most cases to generate enough bandwidth to meet increased customer demand for upstream capacity for years to come. 

But there still is the call of the 10G directive — to meet the speed and latency benchmarks of the wireless industry’s 5G push. And as far as bandwidth goes, the pandemic did show everyone how fast the bar can move.

“Networks didn’t break” amid the pileup of Zoom meetings, online schooling and boffo Netflix usage, Keefe said. “But they were strained a lot.”

As a result, operators are thinking about the future of their plants. But vendors like CommScope are essentially delivering, in a number of cases, the same message as they did in person last year in New Orleans, only this time through computer screens. 

“It’s virtualization squared,” quipped Keefe, who tallies participation for CommScope in 17 different Cable-Tec Expo Zoom and Webex panels, as well as various virtual booth tours and one-on-ones with members of the tech trade press. 

Focus on MACPHY

The cable business’s premiere technology event, Cable-Tec Expo was heavy last year on discussion of the virtualized converged modem termination system (CMTS), as well as pushing the “PHY” layer (an abbreviation for a “physical layer” electronic circuit) out into the network (aka Remote PHY). 

Virtualization will once again be front-and-center at the virtual Expo. Look for that discussion to broaden. 

“People tend to view that virtualization is just about the CMTS, but that actually undersells virtualization,” Keefe said. “The reality is that we’re virtualizing everything in the network.”

This year, Expo attendees will look at products currently in trials — or emerging from testing — that deploy MACPHY, which moves both the PHY and DOCSIS processing (MAC) to the access node. This means that even more network functions are pushed out closer to the customers. 

“Now, Remote MACPHY is ready to go into testing and trials,” Keefe said. “It’s opened up the technology window a little more. There are some other options.” 

Among the new products being showcased by CommScope this week will be the E6000n RD2322 RxD DAA solution, which can operate in both Remote PHY and Remote MACPHY configurations, allowing operators to choose either architecture and enabling those who deploy in Remote PHY to make a transition to Remote MACPHY via software and configuration changes. 

“With this solution, I can put the MAC layer wherever I want to,” Keefe, who describes the varying industry allegiances to Remote PHY and Remote MACPHY as a “religious war,” told Multichannel News.

“I believe Remote MACPHY is the future,” he added.

With industry engineering consortium CableLabs signing off on the broad umbrella specification of DOCSIS 4.0, next-generation DOCSIS technologies will also be a major focus at Expo.

One such innovation is Low Latency DOCSIS, which is actually provisioned for in the current DOCSIS 3.1 standard. 

With the cable industry beginning to face competition from the wireless industry’s fixed 5G push, CommScope will also be presenting plenty of data on Low Latency DOCSIS. 

“The next big thing everyone is going to be focused on is latency,” Keefe said, referencing a future that’s already started, in which wireless operators tout the ultra low latencies of their 5G networks. “And it’s backloaded into DOCSIS 3.1.”

Comcast said it has successfully trialed the DOCSIS-powered network of the future in Jacksonville, Fla.

The cable operator said it delivered symmetrical 1.25 gigabit-per-second speeds to a local-area home using Network Function Virtualization (NFV) and Distributed Access Architecture (DAA) with Remote PHY over DOCSIS-powered hybrid fiber-coaxial network.

Comcast is touting the successful trial as a “milestone” in the cable industry’s journey to what it markets as its “10G” future—one in which operators will deliver super-fast multi-gigabit downstream and upstream speeds with ultra-low latency, surpassing the potential of the wireless industry’s 5G push.

Comcast is engaged in the 10G initiative along with NCTA, CableLabs and SCTE, as well as operators from around the world.

“The great strength of our network technology is that we will have the ability to scale these next-generation speeds to tens of millions of homes in the future without digging up yards, or starting massive construction projects,” said Tony Werner, president of technology, product and Experience at Comcast Cable. “This technology provides a path to meeting the needs of the future and making multi-gigabit symmetrical speeds a reality for everyone, not just a select few.” 

Added Elad Nafshi, senior VP of next-generation access technologies at Comcast Cable: “We’ve been inspired by the work our global technical community has done to advance the technologies that made this performance possible and are proud to begin the process of delivering those benefits to customers.” 

Canadian tech company Vecima Networks has announced the purchase of a large portion of Nokia’s cable access product portfolio.

The acquisition, terms for which weren’t announced, includes Espoo, Finland-based Nokia’s EPON and DOCSIS Provisioning over EPON (DPoE) products. Also included are Distributed Access Architecture technologies Nokia took over when it purchased startup Gainspeed in 2016.

Nokia will retain cable-related products including mobile, routing, transport, fiber, and fixed wireless access technology, along with network operations and customer experience-related solutions.

Vecima’s newly acquired DOCSIS DAA and EPON/DPoE technology and product portfolios will be integrated with its existing Entra-branded Distributed Access product suite.

Nokia employees associated with these technologies will be shifted to Vecima Networks, although it’s not clear as to how many of them will take the British Columbia-based company up on the offer.

“Our cable access solutions have played a very important role in helping to redefine next generation cable solutions and our customers' strategies for addressing evolving network demands using distributed architectures,” said Sandra Motley, president of fixed networks at Nokia, in a statement. “However, the industry continues to go through significant shifts, and we believe the timing is right to transition our cable access business to Vecima Networks. Vecima has the focus, resources and complementary product portfolio needed to support these changes and help operators move toward a Distributed Access Architecture.”

Added Sumit Kumar, president and CEO at Vecima Networks: “Nokia’s portfolio to be acquired aligns perfectly with Vecima Networks’ strategy to provide open, independent, and future-proof cable access solutions that support a multi-vendor ecosystem. The addition of these products and world-class talent broadens our DAA platform and adds 10G-EPON products to our portfolio. In addition to expanding the products and services we are providing to existing customers, we look forward to partnering with service providers around the globe we don’t currently do business with.”

The essential role of broadband networks in the current Covid-19 crisis is well established. A recent article in Multichannel Newsvery well described how cable operators are stepping up to meet demand despite enormous challenges. But what are the short-term and long-term implications of the pandemic on the evolution of the cable infrastructure? We see this play out in three phases on a broad level but with notable differences among operators and in different geographies:

Mitigation

In the near term, operators will resort to short-term measures to meet growing demand. They are freeing up capacity in the downstream spectrum by reallocating QAMs to DOCSIS, increasing compression, continuing node splits and other moves. In the upstream, operators who have deployed DOCSIS 3.1 can leverage the Profile Management Applications and add subcarriers. At the same time, content providers are playing a role by downgrading their content, for example, Netflix and YouTube, or staggering the release of their games, such as Sony and Microsoft.

Cautious investment

The health crisis will inevitably lead to some economic contraction despite the massive recent stimulus package. This crisis will impact small and medium businesses as well as consumers, the sweet market spot for cable operators. At the same time, the recent online spike will not completely go away once the crisis is over. Virtual engagement is here for the long term, and cable operators need to add capacity, particularly in the upstream, to meet new demand characteristics. At the same time, MSOs will not lose track of their 10G vision and will continue to plan for massive capacity expansion, including trialing DAA and virtualization.

Recovery

Over the longer term, this crisis has highlighted the importance of broadband networks, and the utilization patterns will even exceed current projections. Cable operators will need to update their playbooks to ramp up capacity expansion. Such scaling will need a new architecture, and the distributed access architecture and virtualization will be at the heart of these playbooks, along with emerging plans to deploy the recently ratified DOCSIS 4.0 specification for much expanded upstream capacity and low latency.

It is hard to believe, but the entire world is grinding to a halt as more and more communities are forced into lockdown or shutdown to prevent the spread of the Coronavirus. In this bleak and difficult situation, the Internet has emerged as the nervous system of the world, keeping education, business, healthcare and people connected as never before. It is not that people have suddenly discovered the online world, far from it; however, in the space of a few weeks, the world has converted to eLearning, telemedicine, virtual meetings, virtual conferences, and so on. Even religious and arts institutions are streaming to their constituents and the public at large, not to mention the increase in streaming and gaming now that most people are confined to their homes. In February, Cisco saw 22 times the amount of network traffic per second it normally gets for WebEx, according to CNBC. It is likely to be even higher in March.

None of these use cases are new, but they have all of a sudden been adopted on a massive scale. Early reports from Europe suggest a 40% increase in network traffic. Can networks handle this amount of traffic?

To be sure, many of these trends are short term, driven by necessity; for example, schools are repeatedly making clear that eLearning is a short-term measure and is not a substitute to in-person education. Furthermore, the success of these online initiatives requires much more than fast and reliable broadband; at a minimum, they need to be complemented by new processes, appropriate resources, clear expectations, training, and a different IT infrastructure, among other things. However, it is likely that things will not necessarily revert to business as usual when the crisis has passed.

What is clear is that in the near term, the world needs a lot more broadband and needs it to be fast, reliable and affordable. To their credit, ISPs have stepped up to the task. They are removing consumption caps, increasing speed, providing free bandwidth to the under-privileged, and committing their resources to keep broadband networks reliable and functioning in this moment of great need.

Do cable operators have the capacity to meet the exploding demand in the access network in terms of speed, reliability and latency? It is true that the industry has largely wrapped up the deployment of DOCSIS 3.1, which delivers speeds up to 10 Gbps downstream, and operators have been continuously reducing the size of their service groups by splitting nodes. However, the unprecedented demand on their networks may require a new playbook, because this surge may stay with us for a while, and some of the increased usage will prevail for the longer term.

Will this surge in demand be the catalyst for the industry to seriously consider migrating to the distributed access architecture (DAA) on a large scale? Will this need to suddenly increase capacity become a driver to consider virtualized solutions that enable easier scaling in the headends? Will it drive operators to allocate more capacity to upstream?

The cable access network remains limited in the upstream: most operators still allocate only 42 MHz to upstream with a minority allocating 84 MHz. Upstream capacity will become crucial as more people rely on virtual meetings, eLearning, etc. The industry has a good upstream option with the 204 MHz split that is currently supported (as an option) in the DOCSIS 3.1 specifications and that is made available by most major industry vendors. The 204 MHz split can enable 1 to 1.5 Gbps upstream. Of course, there is no free lunch; more spectrum allocated to the upstream means less in the downstream, and there is a need for a guard band or “spectral penalty” of about 54 MHz. The migration to 204 MHz requires changes to existing nodes and amplifiers on the HFC plant.

Multiple operators are already trialing or deploying DAA, particularly the Remote PHY version, and some have already adopted virtualized solutions. It is entirely possible that this trend will gain momentum driven by market need.

It is too early to tell what the long-term implications of this crisis will be. What is certain is that it will not be business as usual when we are finally out of crisis mode, and for broadband providers, it might spur a new cycle of infrastructure investment.

Total cable access “concentrator” revenue declined 31% year over year in the third quarter to $287 million, driven by a continued slowdown in North American CCAP license purchases, according to research company Dell’Oro Group.

The finding, nonetheless, represented an improvement over the second quarter, during which cable access equipment revenue dropped 40% to $237 million.

Overall broadband access equipment revenue decreased 12% in Q3, with a 371% spike in XGS-PON OLT revenue, as well continued growth in XG-PON1 OLT ports and CPE, offsetting the slump in North America converged cable access platform (CCAP) sales.

“Operators’ continued push to increase their fiber investments is resulting in strong Y/Y gains in PON OLT ports,” said Jeff Heynen, Senior Research Director at Dell’Oro Group.

The U.S. cable access market continues to be roiled by technological disruption, with operators pausing orders as they plan migration to network virtualization and distributed access architecture (DAA).

Perhaps more impactful, leading operators Comcast and Charter Communications are reporting healthy growth in subscribers and revenue for broadband services, reducing the incentive to spend money on their networks. 

Making its first appearance at Cable-Tec Expo Show following its purchase of Arris earlier this year CommScope will present three technologies it believes will provide clarity for cable engineers to finally make some forward-looking decisions about their networks ... and start rendering some product orders.

Extended Soft Frequency Division Duplex (FDD) blends elements of Full Duplex DOCSIS and Extended Spectrum DOCSIS, two technologies cooked up by CableLabs to extend the life of hybrid fiber coaxial networks into the next two decades. 

In fact, Chris Busch, CommScope engineering fellow in the office of the CTO, calls Extended Soft FDD “the union of the two technologies,” allowing operators to adjust allocation of bandwidth across the upstream and downstream channels.

Full Duplex DOCSIS has the capability of delivering symmetrical 10 Gbps speeds. But its uptake has been limited by what are perceived to be some inflexible factors.

“If we’re going to make Full Duplex work for us as industry, we need to have ability to use spectrum in many different use cases,” Busch said.

He added that unlike FDX, CommScope’s trials of Extended Soft FDD have revealed no rigid need for a node plus zero network configuration.

“A lot of Extended Soft FDD is amplifier friendly,” Busch said. “It’s a boon to the operator.”

CommScope will make its pitch next week amid a slow sales year for cable access technology vendors in general.

Also speaking to MCN Monday, Todd Kessler, senior VP of product management for CommScope, noted that the shift from centralized integrated CCAP architecture to Distributed Access Architecture (DAA) is one of the biggest technological changes the cable industry has ever made. He believes CTOs will continue to mull these decisions through the calendar year.

To hopefully move the market along, CommScope will also present what it calls DAA Aggregator, a product that lets operators connect up to eight HFC nodes to one Remote PHY device. This significantly increases the number of homes passed per RPD serving group—from 20 to 40 to between 150 to 300—enabling deeper reach into neighborhoods and a simplified path to network upgrades.

Also being demonstrated: DOCSIS Timing Protocol uses precise timing distribution over the DOCSIS networks for time-critical processing and applications, where a fraction of a second means the difference between success and failure. Current and future applications include mobile backhaul, virtual reality, and autonomous vehicle control.

“This is all built around driving the cable operators to better utilize their HFC plant, and breath new life into HFC architecture, taking fiber deeper, and adding to the technology,” Kessler said. 

Cisco has confirmed major changes to its cable access supply business.

One is personnel related. John Holobinko, Cisco’s director of cable access strategy, quietly exited the company over the spring. According to the North Carolina native’s LinkedIn profile, he departed his Charlotte-based position at Cisco in April and is now working nearby as president and CEO of the Pineville Chamber of Commerce.

Separately, Cisco has confirmed that it has stopped investment of time and money into Full Duplex DOCSIS. (This news was first reported by Light Reading.)

“Cisco has internally communicated that we are suspending further investment in Full Duplex DOCSIS (FDX) until the market timing, ecosystem development and size of the opportunity can be quantified,” Cisco said in a statement provided to MCN. “We remain confident that FDX will play a critical role in realizing 10G symmetrical cable services in the future and are committed to continuing the pioneering work with our customers to transition from centralized to distributed architectures. Cisco continues to lead innovation in the cable industry, exploring many ways to help cable operators modernize their access networks with our unparalleled end-to-end portfolio."

A Cisco rep said Holobinko left to "pursue other interests" and that his departure was unrelated to the company's shift in cable access strategy.

Holobinko was the top strategy executive for Cisco’s cable access division. When MCN last spoke to him during October's SCTE Cable-Tec Expo in Atlanta, he was in the process of leading his division’s transformation from a supplier of proprietary hardware, such as the CBR8 Cable Modem Termination System (CMTS), to becoming a vendor of software that virtualize cable access technologies. Cisco was also moving into Distributed Access Architecture and Full Duplex DOCSIS under Holobinko’s watch.

As for the suspension of FDX activities, the tech was first introduced in 2016 by cable industry research consortium CableLabs. Full Duplex DOCSIS promises to deliver symmetrical 10 Gbps speeds over hybrid fiber coaxial wiring.

Comcast has publicly stated that FDX is part of its future network development planning. However, the technology requires an “N+0” configuration, meaning fiber has to be pushed out much closer to the customer. Amid a broader “10G” marketing push that’s designed to match the wireless industry’s 5G hype, CableLabs is now hoisting myriad next-generation broadband technologies on the cable industry, including Extended Spectrum DOCSIS, which many believe is competing technology to FDX.

Adding DAA and virtualized Cable Converged Access Platform (CCAP) to an increasingly complex decision making mix, operators are pausing their orders and contemplating a lot of complexity in terms of designing their network of the future.

Research company Dell’Oro Group said cable access vendor revenue was down 38% in the first quarter to $275 million. According to Dell’Oro analyst Jeff Heynen, the slowdown came as “cable operators push off new capacity purchases while they determine how to move forward with distributed access architectures.”

Cisco is one of the three incumbent companies, along with CommScope’s recently acquired Arris, and Casa Systems, which have controlled the cable access technology business. However, boosted by recent deals with Comcast and Liberty Global for its CableOS virtual CCAP product, Harmonic is having a disruptive presence in the market.

Last week, CommScope announced the departure of Bruce McClelland, the former Arris CEO, who had been propped up as COO of the combined company, overseeing the integrated Arris brand. This came amid slowing overall business for Arris, punctuated by slow cable access sales.

For its part, Cisco reports its own earnings, for its fiscal fourth quarter, on Wednesday. 

Casa Systems became the latest cable access technology vendor to report a really tough first quarter, with revenue off a whopping 55.6% to $35.5 million.

The Q1 report from the Andover, Mass.-based Casa follows a similar call from competitor Harmonic earlier in the week, one which revealed a 30% slide in cable access sales for the first quarter.

“We’re seeing an industrywide slowdown as cable operators implement a shift to virtual CCAP and DAA,” Casa Systems CEO Jerry Guo told investors, describing a “quarter we’re not at all happy with.”

Related: Harmonic: Volume Deployment of CableOS is on the Way

Guo cited recent figures from S&P Global, which noted that cable access tech sales were off 26% combined in the fourth quarter for the category’s three biggest vendors, Arris/CommScope, Cisco and Casa Systems.

As Harmonic did two days earlier, Casa said his company’s clients are engaged in an abundance of active trials for virtualized Converged Cable Access Platform (CCAP) and Distributed Access Architecture. Guo cited 67 trials in all.

But as operators mull a revolutionary way to build out their networks, “we’re in a holding pattern,” Guo conceded.

Casa Systems has tried to diversify its product lines towards wireless convergence recently. But Q1 sales in this emerging category didn’t come close to offsetting the slowdown in the company’s core integrated CCAP business.

Speaking more broadly about the CCAP situation, Guo cited the massive investments made by MSOs in recent years to deliver gigabit speeds.

“The pace of network upgrades has slowed significantly as the industry has moved to capacity filling vs. the buildout phase,” he said.

Notably, also like Harmonic, Casa Systems is banking on MSO clients getting off the dime on the emerging cable access tech paradigms and rolling out some deployments later this year. Casa is still forecasting $250 million - $300 million in full-year 2019 revenue.

“We believe we are at an important juncture in the development of our business and I remain confident that our recent results are not indicative of the company’s large future opportunity,” Guo told investors. 

The DAA revolution is coming, Harmonic insists, it’s just being delayed a quarter or two due to some integration issues occurring with the company’s largest clients.

That was the message put forth during Harmonic’s first-quarter earnings call Monday. The technology vendor’s virtualized cable access technology, which it calls CableOS, is one of the most closely watched product lines in the cable industry right now, threatening to upend the hegemony enjoyed by CommScope-owned Arris, Cisco and Casa Systems.

Harmonic said that 670,000 cable customers are getting their network service through CableOS right now in markets mostly in the U.S. and Europe, a 24% uptick over the first quarter of 2018.

However, the company’s Q1 revenue from cable access products was only $12.9 million, down considerably from the $18.5 million generated in the first quarter of last year.

Harmonic’s stock cratered more than 5% following Monday’s call, with investment analysts concerned about the company’s ability to live up to full-year guidance of $100 million - $130 million in cable access revenue.

For his part, Harmonic CEO Patrick Harshman said he expects CableOS revenue to start ramping up quickly starting in the second quarter. Harmonic has loosely identified four Tier 1 clients in North America and Europe as being in various phases of testing CableOS, with one of those customers widely suspected to be Comcast.

“There was a couple of major architectural change decisions made by our lead customers,” Harshman said. “And going into the beginning of the year, frankly, there was a little bit of uncertainty about the exact timeframe that those could be implemented and how we would kind of get back on track. But the good news is all that work is just about done. And we feel as though we're largely currently getting back on track.”

One investment analysts asked, might there be unforeseen competitive forces actually causing these delays? 

“We don't know what we don't know,” Harshman conceded. “We have not heard of anything else being demoed in the lab, successfully and competitively. It’s prudent not to be over-confident. But it’s hard to imagine, frankly.”

Numerous operators, including Comcast, are aggressively moving to Distributed Access Architecture (DAA), pushing fiber deeper into the network and moving network functions out of the plant and closer to customers. This process walks hand in hand with virtualization of network functions like Cable Modem Termination System (CMTS). Meanwhile, a number of Tier 2 & 3 clients aren’t necessarily migrating their networks to DAA, Harmonic said, but are rather simply subbing in virtualized components as they swap out DOCSIS 3.0 network infrastructure for the newer DOCSIS 3.1 standard. 

When the cable industry launched its “10G” counter-marketing campaign at CES in January, the common interpretation was that the initiative revolved around Full Duplex DOCSIS (FDX), a CableLabs technology that is expected to eventually deliver 10 Gbps symmetrical broadband speeds.

As it turns out, the branding exercise—intended to counter the wireless industry’s aggressive promotion of next-generation 5G network technologies—is a bit broader than that.

Related: CES: Cable Declares It Won’t Be ‘Second to the Door’ to 5G With ‘10G’ Branding Launch

Speaking at an event produced and covered by Light Reading in Denver last week, CableLabs President and CEO Phil McKinney described 10G as a “collection of technologies,” including Full Duplex.

In a report issued last week, investment research company Cowen said 10G "is essentially a common platform that will involve a variety of technologies that CableLabs members can pick and choose from, in incremental steps, and that will begin trialing in 2020.

“Specifically, the 10G initiative involves various tools and features including low latency, improved security, a distributed access architecture (DAA, decentralizing the network, virtualizing the headend, and extending the digital/IP aspects of the network for speed/function enhancements), Full Duplex transmission (FDX, high speed in both directions), fiber deep, the N+0 architecture (no amplifiers needed between nodes and HHs), and subsequent meaningful opex/capex benefits,” Cowen added.

Notably, 10G’s collection fo broadband technologies will ultimately allow for speeds as high as 14.2 Gbps, with the “10G” sounding better for marketing. Cisco has noted that there will eventually be a pathway for 25 Gbps down and and 10 Gbps 10 up in the next 5 to 10 years.

Cowen believes that should be enough to ensure that the cable industry enjoys a broadband speed advantage over the next decade.

The research company concedes there is concern in the investment community that cable’s speed advance might be become “overkill,” with 5G stepping in over the next few years, sating a demand for some “killer app” in the home with modest speeds of 100 Gbps - 500 Gbps.

Tier 3 operator Midco, Cowen noted, recently conceded that only 3% of its broadband customers pay for 1-gig services. The research firm estimates that only around 8-10% of customers for Comcast and Charter have 1 Gbps.

Cowen cited Niesen’s Law, which states that consumer broadband demand will continue to increase at a rate of 50% a year. Some operators are being a compound annual growth rate of 35-45% for download speeds. Cowen predicted adoption of 4 Gbps speeds by the mid-2020s, and 10 Gbps speeds thereafter, which it believes will outpace what 5G can deliver.

The “killer apps” of this longer term future could be things like 3D holographic messaging, which would require speeds greater than 800 Gbps, and 360-immersive VR gaming and entertainment.

“We continue to believe the <6 GHz fixed wireless threat will be relegated to niche low-income/rural plays,” Cowen said. 

San Jose, Calif. cable technology vendor Harmonic saw a 12% year-over-year revenue spike to $113.6 million in the fourth quarter on the strength of its CableOS virtual CCAP platform.

Revenue for the company’s cable access segment increased 79% to $24.1 million, with gross margins in the quarter reaching 43.6%.

CableOS, a software-based iteration of Converged Cable Access Platform (CCAP), is in 29 commercial and field trials currently, Harmonic said. Participating companies include four out of the top eight North American and European cable operators.

Harmonic said 535,000 cable modems are being served globally by CableOS network technology, an 11% increase over the third quarter. Related to the move toward virtualization, Harmonic said it shipped 1,000 notes designed for the emerging paradigm of Distributed Access Architecture during Q4.

“These initial CableOS deployments are primarily in a traditional centralized CMTS architecture with a typical application as DOCSIS 3.1 upgrade, and virtualized software economics, and future distributed network migration flexibility underpinned our competitive advantage. We expect continued momentum during 2019 for these more traditional applications,” said Harmonic CEO Patrick Harshman, during Monday’s earnings conference call.

Referring to DAA as a “cousin” of virtualization, Harshman said he doesn’t envision the copious ongoing trial activity surrounding DAA to translate into swift commercial sales until late this year.

“Based on challenging, but groundbreaking progress made over the past several months, we expect the volume of 2019 deployments of new Distributed Access Architecture or DAA networks with multiple tier 1 operators,” he said.

“During this quarter of Q1, we will still be on the on-ramp, continuing support of lead customers who are now in the process of implementing specific trial informed improvements to their deployment plans, not to the CableOS core, which has been solid for some time, but rather to ancillary networking and orchestration elements of our customers end-to-end DAA implementations,” Harshman added.

Harmonic also saw video segment revenue increase by 22% to $89.5 million, driven partly by a 58% sequential uptick in UHD shipments.

Despite a strong fourth quarter that met guidance, Harmonic signaled that Q1 will be below guidance, sending its stock price down double digits in after-hours trading. 

ATLANTA - As it crosses the finish line on an 18-month mission to deploy DOCSIS 3.1-enabled services across its entire footprint, Comcast is already testing a new network configuration mixing Distributed Access Architecture with Full Duplex DOCSIS capabilities.

According to Robert Howald, VP of network architecture for Comcast, DAA is a "prerequisite to Full Duplex,” with the operator looking to deploy Full Duplex-capable, Remote PHY nodes.

“We see DAA as part of the train of evolution. We’re not going to wait years for Full Duplex to start deploying DAA” said Howald, VP, speaking at a pre-SCTE Cable-Tec Expo event Monday focused on DAA and featuring engineer representatives from a host of major operators, vendors and standards bodies.

Complete Coverage: Cable-Tec Expo 2018

While compound annual growth rates (CAGR) for demand of downstream bandwidth is decreasing, the CAGR is increasing for upstream broadband, up to about 25% - 30% from a longtime plane of around 20%. This can be credited to the proliferation of devices like surveillance cameras, but also the emergence of applications like virtual reality and advanced gaming.

“We want to go symmetrical,” Howland said, noting the 10 Gbps speed potential, in both downstream and upstream, for Full Duplex DOCSIS. “But we want to be in DAA to do that.”

DAA, he added, will “lead Comcast down the road to virtualization” of its network, allowing the operator to use “off-the-shelf” server components and delivering “tremendous scalability benefits for us at our head end.

Related: Comcast Reaches the Finish Line on DOCSIS 3.1 Deployment

“We prefer not to build new facilities if we don’t have to,” Howland added, echoing comments made minutes earlier by CableLabs’ Jon Schnoor on the potential of DAA to save on infrastructure real estate expansion, not to mention on cooling and power needs.

Howland offered up no specific time frame for deployment of DAA and Full Duplex (FDS) services. However, speaking shortly afterward, Steven Krapp, senior director of technology for vendor MaxLinear, said his company is working with Comcast on FDX trials, “seeing how the cable swinging in the wind effects the echo cancellation.”

With echo cancellation being core to a technology that involves the upstream and downstream frequency layers existing on top of one another, FDX requires that operators move to a node+0 environment. This isn’t as much of an issue for a company like Comcast, which has “pushing fiber deeper and deeper into its network,” according to Howland, almost reaching the point of the “optic nerve” of the subscriber.

But it is an issue to many operators, which don’t envision having a node+0 configuration in a 10-year time window.

According to Krapp, MaxLinear is working FDX amplifiers that will enable the technology to work beyond node+0. 

Arris has named four-year company veteran Kevin Wirick to lead its new “Network Intelligence and Automation” business.

The new unit will focus on developing, making and selling cloud-based network management solutions to operator customers. Wirick’s team will operate under the umbrella of Dan Whalen’s Network and Cloud business unit. Wirick will report directly to Whalen.

With Arris clients increasingly using Distributed Access Architecture (DAA) technologies, the vendor said network processing has increased by a factor of 10 to 100. The products developed and sold by Wirick’s team will aim to simplify network provisioning, enable efficient scaling, and provide insights to help reduce operational costs.

Products overseen by the the group include Eco Service Management, a platform that operationalizes the delivery and management of WiFi, triple play and connected home solutions; and ServAssure, which monitors the network pipeline

Wirick joined Arris in 2014 from Motorola and previously led its video network infrastructure business. 

Network engineering leaders from Comcast, Charter, Cox, Shaw and Denmark’s Stofa will headline the speakers at a seminar focused on Distributed Access Architectures (DAA), which will help kick off this year’s SCTE•ISBE Cable-Tec Expo in Atlanta on Oct. 22.

A follow-up to last year’s Remote PHY seminar at the Expo in Denver, this year’s event will address the ability of DAAs and the Headend Rearchitected as a Datacenter (HERD) to drive cost efficiencies, decrease time to market and increase customer satisfaction. The Society of Cable Telecommunications Engineers says more than 600 attendees are already registered.

Related: SCTE Announces Finalists for Energy 2020 Adaptive Power Challenge

Speakers include Kevin Kwasny, principal enter for Charter Communications; Rob Howald, VP of network architecture for Comcast; Jeff Finkelstein, executive director of advanced technologies for Cox Communications; Jamie Brown, director of network technologies for Shaw Communications; and Kjeld Balmer, head of network technology for Stofa A/S.

On the vendor side, speakers include Arris’ Tom Cloonan, CTO for network solutions, and Mike Emmendorfer, VP of systems engineering and architecture; Peter Wolff, VP of wireline product management for Casa Systems; John Chapman, CTO of cable access and fellow at Cisco; Asaf Matatyaou, VP of solutions and product management at Harmonic; Barak Hermesh, owner of network technology for the Intel Network Platforms Group; Steven Krapp, technical marketing director at MaxLinear; Jeff White, head of cable strategy and business development at Nokia; Timon Sloane, VP of marketing and ecosystem from the Open Networking Foundation; and Colin Howlett, VP of architecture for Vecima Networks.

Related: Charter, Comcast, Cox Execs Added to Cable-Tec Expo Opener

The event is jointly sponsored by CableLabs, which will also have two technologists present—Doug Jones, principal architect, and Jon Schnorr, lead engineer for network technologies. 

Arris said that European operator Eltrona is the latest cable company to deploy its Remote Pay distributed architecture solution to deliver DOCSIS 3.1-powered 1-gig broadband service in Luxembourg.

Eltrona is using the Arris E6000 Gen 2 converged cable access platform, along with E6000N R-PHY, which provides both the CCAP core and R-PHY device. In this approach, which is defined in the CableLabs Modular Headend Architecture, the PHY layer is moved from the CCAP into a node or remote shelf, but the MAC processing, provisioning and monitoring functions remain in the headend.

Related: Arris Touts Euro Customer ‘Wins’ at IBC

Also being deployed: Arris Touchstone TG3443 Cable Voice Gatgeways, which include 4x4 802.11ac dual band radios.

“Our focus for the remainder of the year continues to be on expanding our E6000 footprint,” declared Arris CEO Bruce McClelland during Arris’ second-quarter earnings call in August.

“With its market-leading density and throughput, coupled with its flexibility to support DOCSIS3.0, DOCSIS3.1, video and Remote PHY, [the E6000] continues to provide the best value for cable operators,” McClelland added. “And you can watch for a new DOCSIS3.1 launch announcement from a major international customer over the next few weeks that leverages our full Network & Cloud portfolio, as well as CPE products.”

Casa Systems cut its revenue guidance by $50 million for the rest of the year this week, explaining that its cable operator clients are putting off longterm investments on network expansion as they mull their big moves to virtualized architectures.

Speaking to investors during Casa’s second quarter earnings report, company president and CEO Jerry Guo said customers are making only short-term investments on network capacity expansion, eschewing high-capacity purchases of Converged Cable Access Platform hardware as they mull their strategy on next-generation Distribute Access Architecture (DAA).

Related: Casa Systems Shrinks IPO Size to 6M Shares at $13 Each

“Over the last few weeks, it has become clear to us that we are witnessing a pattern shift in procurement in the cable market,” Guo told investors, according to a transcript provided by Seeking Alpha. “While our customers weigh the timing for their large-scale rollout of the next network architecture, they are choosing to only procure capacity in a short-term basis. And they're not making very long-term upgrades of the chassis-based products in some cases.

“We do see DAA delayed industry wide in terms of large scale deployment,” Guo added. “And given that a lot of operators are contemplating DAA, they are slowing down their spending in their current capacity expansion.”

Guo said believes larger scale DAA deployment will begin in 2019.

Of course, none of this is helping Casa’s bottom line in the short term. The company’s stock is down around 23% since its Tuesday earnings report, during which it cut full-year revenue guidance to as low as $330 million.

Casa reported second quarter revenue of $68.7 million, up 3.1% from the year-ago quarter, but down 23% from the first quarter of this year.

"Where other network architectures like wireless networks have gradually pushed fiber closer to the cell tower and increased bandwidth as demand has grown, DAA requires an unprecedented step change in access architecture and bandwidth that brings significant challenges." —Jon Baldry, Infinera

The cable industry is buzzing with the prospect of distributed access architectures (DAA) and the resulting step change in end-user experience. DAA is a once-in-a-generation architectural change that will enable cable MSOs to defend their competitive advantage in terms of broad content offerings built upon industry-leading bandwidth per user.

DAA has many facets, but from a data aggregation and backhaul perspective, the biggest change is the fiber-deep push within the access network. Migration to Wavelength Division Multiplexing (WDM)-equipped Remote PHY devices (RPDs) requires the previous WDM-based transmission network to extend from secondary hubs deeper into the access network, connecting directly to the RPD.

This sounds like a simple proposition — WDM has pushed deeper into access networks over the last decade as fiber availability has increased and technology costs have dropped. Why shouldn’t DAA be another example of this, with a gradual push for WDM deeper into the access network to support the rollout of RPDs?

The reason it is not is the significant increase in scale that DAA drives into the underlying transport network. Where other network architectures like wireless networks have gradually pushed fiber closer to the cell tower and increased bandwidth as demand has grown, DAA requires an unprecedented step change in access architecture and bandwidth that brings significant challenges.

If we look at a typical residential area served by a cable MSO, the secondary hub serves clusters of approximately 500 homes passed with an optical node or optical network termination and a corresponding amplified hybrid fiber coaxial (HFC)-based access network with five or more HFC amplifiers per network. To achieve DAA, 10 or more RPDs could be deployed within this network to remove most if not all these HFC amplifiers. Looking at the U.S. market as a case study, we can understand the number of RPDs that will be required. U.S. cable networks pass around 122 million homes, and as RPDs typically support 50-60 homes passed, a simple calculation gives us a market of around 2 million RPDs, each with a new 10G DWDM backhaul link into the transport network. Unfortunately, residential areas haven’t always been built in convenient clusters of 50-60 homes, so the actual number of RPDs required in the U.S. may be closer to 3-3.5 million.

Those figures address the macro-level requirement for new 10G DWDM access circuits driven by DAA. At a more local level, secondary hubs vary in size, but the largest will need to support 600-700 RPDs, and more in cases of secondary hub consolidation. We therefore have a twofold challenge--a massive rollout of new 10G DWDM access circuits across cable networks, and huge concentrations of these circuits within secondary hubs that are often already space and power constrained.

Looking first at the hundreds of thousands of 10G circuits that will hit the DAA access network, we must consider how to address the operational aspects of the rollout. The key requirement is simplifying the rollout process through automation. Autotuneable WDM-PON technology that allows the network to tell the remote optic which wavelength to tune to automatically has been around for several years, but with limited bandwidth and reach. Recent technological advances have extended both capacity and reach, making this an option for DAA and other fiber-deep deployments. Autotuneable DWDM optics deployed within the RPD will enable deployment engineers to treat them like grey optics, without the need for knowledge of WDM or the exact WDM wavelength requirements of the specific location. This will greatly simplify the process, reduce spares holding costs and decrease the likelihood of deployment errors.

Returning to secondary hubs, again operational issues need to be foremost in our minds. Key issues to consider in the secondary hub are:

• Space and power – real-world deployment scenarios are often space and power constrained, and DAA transport and aggregation solutions must capitalize on available space and minimize power consumption. 
• Fiber management – Many secondary hubs will terminate 600+ RPDs, meaning 1,200+ fibers connecting the WDM filters to the aggregation platforms before other connections within the rack are considered. Scalable DAA transport solutions must address this critical issue.
• Automation – DAA will capitalize on the most advanced automation and network optimization trends, such as autotuneable optics to the RPD and the central office rearchitected as a data center program. DAA aggregation switches must support these initiatives to ensure that MSOs can keep ongoing operational costs down while allowing networks to rapidly scale.

DAA will allow MSOs to fight off alternative access providers and keep their competitive edge. It brings considerable challenges throughout the network, and those within the transport and aggregation domains shouldn’t be underestimated. The good news is that the optical networking industry is innovating to address these operational challenges, allowing the transport network to be rolled out quickly and simply, then rapidly scaled to deliver on the promises of DAA.

JonBaldry is director of the metro business unit of Infinera, an optical networking solutions company based in Sunnyvale, Calif.

Targeting an opportunity rising as cable operators pursue new distributed access architectures, ATX Networks this week introduced a new digital optical gateway platform that will support their move to remote PHY and remote MACPHY networks.

The first entry for the company’s platform, marketed under the GigaWave brand, is the Digital Link Extender 40 (DLX40). The 1-rack-unit DLX supports two DLX40 modules, with each capable of aggregating up to 40 wavelengths across optical access links of up to 60 kilometers in length, ATX Networks said.

ATX, which introduced the new line amid this week’s AngaCom show in Germany, believes its approach with digital optical technology will fit in with cable’s pivot to distributed access systems that aim to create more capacity, reduce headend space and power requirements, while also supporting the growing need for those networks to backhaul mobile and wireless small cells for today’s 4G networks and the 5G networks of the future. The move to distributed access also fits in with future Full Duplex DOCSIS networks that will support multi-gigabit symmetrical speeds.

RELATED: Full Duplex DOCSIS Interop Testing on the Horizon

ATX says its new lineup will help MSOs evolve analog networks to digital and help to underpin the move to software-defined, virtualized distributed access architectures, Charlie Vogt, ATX Networks’s recently named president and CEO, explained. He said a portion of the work partially stems from ATX’s acquisition of InnoTrans.

RELATED: Charlie Vogt Named President, CEO of ATX Networks

ATX said a “marquee MSO” in North American has selected GigaWave DLX as a component of its next-gen distributed access architecture (DAA) initiative. The MSO wasn’t named, but deployments are slated to start this fall, the company said.

“We’re seeing a lot of RFPs and RFIs coming out” for DAA projects, Vogt said.

ATX is also developing a next-gen, “universal” node for DAA and Remote PHY and Remote MACPHY environments.

ATX’s new GigaWave products will be designed to work with those nodes as well as remote PHY nodes developed by other suppliers. 

Denver – Whether it involves technical specifications or plans involving trials or deployments, the cable industry continues to push ahead with next-generation, distributed access network architectures that will help to pave the way to the virtualization.

But there’s still some uncertainty in terms of the speed at which those transitions will get under way as MSOs look to distributed access architectures (DAA) to push fiber deeper into their networks and enable higher fidelity digital optics, while also reducing the space and power requirements of their headend and hub sites.

While 34% of operators surveyed last year expected to have preparations for distributed access architectures (DAA) underway in 2018, the expectation now is that bigger deployments will likely get pushed into 2019, Jeff Heynen, consulting director at SNL Kagan, said here Wednesday at Light Reading’s Cable Next-Gen Technologies & Strategies event.

Still, “it’s very clear…that distributed access is going to be a major factor in terms of the revenue tie” for cable access network technology,” he said.

RELATED: Forecast Gets a Fix on Next-Gen Cable Network Tech Spending

CableLabs, meanwhile, has been moving forward with specs for DAA and Distributed CCAP Architectures (DCA) that aim to ensure interoperability between suppliers. Taken together, CableLabs’s DAA-facing efforts include several areas such as Remote PHY, Remote MACPHY, and Full Duplex DOCSIS, and its work with coherent optics.

Jon Schnoor, lead engineer, wired technologies at CableLabs, said the specs for Remote PHY are nearing an end, with 11 interop events already completed, and have already moved into the qualification stage. Spec writing for Remote MACPHY, which introduced a new component called the MAC Manager, is underway.

RELATED: CableLabs Moves Ahead with Remote MAC/PHY

In addition to Remote PHY devices (RPD), CableLabs’s work also extends to include a new device called a Remote MAC Device (RMD) that moves the CCAP functionality into the node.

As part of some phase II work, CableLabs and its constituents are also working on something called the Remote MAC Core, which can be put in the node, headend or hub. That, Schnoor explained, will give operators the flexibility to put that functionality wherever they need it on depending on their power and space limitations.

Phase III, with a 2019 timeframe, will aim to virtualize the DCA portion of DAA, and utilize a software-powered control plane.

These approaches should enable operators to distribute more functions toward the edges of the network over time and free up space in headends and hubs, or possibly eliminate the need for them altogether.

MSOs, meanwhile, are also moving ahead with DAA and virtualization plans as that work at CableLabs continues.

WideOpenWest, for example, has teamed with Nokia on a Remote MACPHY initiative that is initially focused in Cleveland and Chicago.

Cash Hagan, WOW’s chief operating officer, said new nodes are going in today, with an initial focus on saturated parts of the network. Later this year, WOW will expand that work into additional markets, and will also start to install a distributed access node anytime one needs to be cracked open, he added.

Hagan said a key driver is to build more capacity into the network while achieving other capex and opex benefits that it gets as it cuts down on space and power needs in headends and hubs. “The only way to get there is by distributing the network,” Hagan said.

Comcast is also pursuing a DAA initiative with a focus on Remote PHY, which it says can add value in a number of different architectural models currently in place in its network.

In addition to the power and space benefits, it will also simplify the network and enable Comcast to get a real-time view into the performance of its network.

With service reliability being a paramount factor, having that instant visibility into the network “is critical to everything we want to do going forward,” Elad Nafshi, Comcast’s senior vice president, next generation access network, said here during a keynote later in the day.

Nafshi, who sees the access network becoming an epicenter of cable innovation, also confirmed that Comcast’s DAA activities will focus on Remote PHY.

Cable operator spending on two key network-facing initiatives – distributed access architectures (DAA) and new “virtual” converged cable access platform (vCCAP) implementations – is poised to ramp up over the next five years, according to a new forecast from Kagan, a media research group within S&P Global Market Intelligence.

RELATED: Ramping Up for Remote PHY

Amid MSO plans to move ahead with multi-year transitions to next-gen technologies, Kagan sees spending on remote PHY and remote MACPHY optical nodes – elements that move important electronics and functions of traditionally centralized CCAPs toward the edge of the network – jumping from $60.9 million this year to $544.7 million in 2019 and $969.2 million in 2022.

RELATED: CableLabs Moves Ahead with Remote MACPHY

Kagan is also forecasting that virtual CCAP/CMTS revenue will climb from $20.5 million in 2018 to $536.3 million in 2022, anticipating that operators in North America and Western Europe will lead the way initially in virtualizing a “small percentage of their systems.”

The moves toward DAA and software-driven vCCAPs are entering play as MSOs strive to add capacity to their networks while also reducing the headend/hub space, cooling and powering requirements that come with traditional, centralized, chassis-based CCAP products.

And while the amount of spend that will go toward the access network won’t rise a huge amount even as more of that money goes toward DAA and virtual CCAP deployments (with a good portion of going to market-leading, incumbent CCAP suppliers), those initiatives are likewise expected to open up opportunities for others that are trying to elbow their way in.

“It’s clear that there will be opportunities for those new suppliers,” Jeff Heynen, consulting director at SNL Kagan, said.

Of recent note, Sweden’s ComHem is starting to deploy a centralized virtual CCAP approach in partnership with Harmonic and its “CableOS” platform, and WideOpenWest is pushing ahead on a DAA project with Nokia.

RELATED: Harmonic IDs a Real Deployment for Its Virtual CCAP

Heynen said getting a handle on space constraints will likely be the biggest initial driver for vCCAP deployments, noting that some MSOs are “feeling the pinch” in their headend and hub sites as they continue to need to tack on capacity.

However, he stressed in his study that even MSOs that are early to the game with virtual CCAP deployments will be operating co-existing virtual and non-virtual CCAPs for a number of years.

With the dramatic expansion of applications and OTT content, the demand for bandwidth is constantly rising. As a result, MSOs are currently undertaking a major network transformation towards Distributed Access Architectures (DAA), such as Remote PHY, Remote MAC, and Fiber Deep to drive digital traffic over fiber closer to the customers.

Deploying WDM technologies allow existing fiber infrastructure to be leveraged for DAA.

Driving digital optics out of the headend and into the outside plant presents practical challenges for network operators. DAA nodes exist in the cable plant, outside the relative comforts of the headend, where robust environmental control systems with backup power do not exist. WDM technologies are especially at risk in these environments.

Operation at the extreme temperatures in these environments is critical to network performance, and so there are a few practical considerations that need to be taken into account by MSOs.

Practical Consideration No. 1: Know The Lingo

It’s essential to understand the commonly used terminology that governs how network devices are recommended for deployment, especially in regards to temperature.  

The key terms to keep in mind are Commercial Temperature (C-Temp), Industrial Temperature (I-Temp) and extended temperature. C-Temp is the most common envelope for standard use in controlled environments and stretches from 0°C to +70°C, while I-Temp, which stretches from -40C to +85C, is recommended for devices deployed outside of climate controlled environments, such as customer premises sites, outdoor electronics cabinets, mobile antennae sites, and cable television return path nodes. Extended temperature is not a recognized envelope, but is used when devices can operate properly outside the C-Temp envelope, but fail to meet full I-Temp requirements.

Practical Consideration No. 2: Optical Transceivers are Impacted by the Physical Environment

Wavelength drift impacts all types of optics, WDM and standard gray optics alike. Fiber optic wavelengths fluctuate around their center wavelength over time. Common factors that impact the drift are time and environmental temperature conditions.

WDM technology uses passive WDM devices to multiplex multiple circuits on to a single fiber or fiber pair.  WDM passive devices have a ‘passband’ that essentially acts like lane markers or dividers in a swimming pool. The passband ensures that each wavelength stays in their own lane as it is transmitted across the fiber optic circuit. Like a swimming pool lane divider, there is a certain amount of room for WDM wavelengths to drift within the lane.  As in a swimming competition, should a wavelength drift outside of its assigned lane or passband, the passive device will penalize by dropping the transmission.

Practical Consideration No. 3: don’t Take Wavelength Performance for Granted

Performance over temperature over time cannot be taken for granted. Research has shown that temperature cycles over time can indeed impact the long-term performance of WDM optical transceivers. The behavior of the WDM laser may become less predictable with multiple temperature cycles.

Practical Consideration No. 4: Not All Transceivers are Created Equal

The transceiver marketplace offers two approaches to ensuring performance over temperature. First is the “should be good enough” approach, where transceivers are screened in the factory. The screening may include reading optical test results or perhaps placing the transceiver in an environment chamber. The key point for network operators to consider is that the transceiver may perform at temperature at “birth,” but it does not consider the effect of temperature cycles over time on the transceiver.

The second option available is transceivers that incorporate wavelength stabilization technology to ensure WDM wavelengths remain in their “swim lanes” over time and temperature.

Two of the common wavelength stabilization technologies are heat-assisted and thermo-electric cooling. Both technologies are integrated on to the micro-controller of the transceiver and are transparent to the network switch or element.

In conclusion, practical considerations for distributed access archictectures must account for the impact of the environment on digital optics deployed in the field. Ensuring that your WDM optics deployed in the field incorporate stabilization technology is one practical step to network performance over temperature over time.

Ray Hagen is Americas Product Manager at ProLabs, a maker of OEM-compatible optical transceivers and connectivity products

There’s been a debate roiling in cable engineering circles about the pros and cons of Remote PHY and Remote MAC/PHY, options being weighed as operators mull new Distributed Access Architectures (DAA) that aim to boost capacity while also reducing their power and space requirements in the headend or hub.

Nokia holds that the debate has been rendered moot following the debut of a new virtualized DAA platform that features a “universal” cable access node that can be configured to run as a Remote PHY (RPD) device or Remote MAC/PHY (RMD) device.

In addition to reducing space and power requirements, cable operators are also looking for DAA to improve the fidelity of the outside plant and to help them drive more capacity for DOCSIS 3.1 and set them up for Full Duplex DOCSIS, an annex for D3.1 that will support multi-gigabit symmetrical speeds and require a node+0/deep fiber network in which there are no amplifiers between the node and the home.

The new node, Nokia claims, can turn the MAC portion on or off, because it’s been reduced to an independent software virtual network function that can be controlled remotely by the cable operator.  

“We believe we’ve ended the debate,” Jeff White, head of cable strategy at Nokia’s fixed networks group, proclaimed, holding that the dividing line between the two options is now “quite small” and that this is the sort of breakthrough that makes this part of the architecture decision a secondary one for MSOs.

He added: “It’s a piece of software” that can run in a server, in a traditional CCAP [converged cable access platform] chassis or in the node itself.

Nokia, whose work in this area stems from its 2016 acquisition of Gainspeed, plans to show off its new platform at next week’s SCTE•ISBE Cable-Tec Expo in Denver.

RELATED: Nokia Nabs Gainspeed

The product set and features for Nokia’s virtual DAA platform include a virtualized CMTS (that includes the DOCSIS MAC), the aforementioned universal node, and an access controller that can support both Remote PHY and Remote MAC/PHY.

Nokia’s move will also put some completive heat in other vendors that have launched or are developing DAA products, a group that includes Arris, Cisco Systems, Casa Systems, Harmonic and Huawei.

The toggling capability represents a new approach for Nokia, as Gainspeed had previously been pushing a technology agenda that centered on Remote MAC/PHY. White said the “light bulb went off” about this more flexible approach as operators started to think more critically about their network functions virtualization (NFV) and software-defined networking (SDN) strategies.

White said Nokia has found that operators are looking at both options, as one or the other might work better under circumstances, scenarios and conditions.

If space in the headend is major issue, he said, a Remote MAC/PHY approach might make more sense, and allow operators to reduce or eliminate hubs. Remote MAC/PHY might also be better suited for a strategy in which an MSO is looking to centralize and virtualize the bulk of the command and control mechanisms from a centralized system or data center.

Remote PHY, he added, might be a better option if power is limited in the cable operator’s outside plant, as a Remote MAC/PHY node is likely to require between 5% to 10% more power than a Remote PHY node, which requires less processing horsepower.

White said operators are looking at a “cap and grow” approach to DAA as well as some specific use cases, such as a “hotspot” on the network or in contested MDU environments. Still others might go at it hub-by-hub as they look to consolidate those.

Nokia hasn’t announced any deployments, but Comcast, Liberty Global and WideOpenWest were among the MSOs that praised Nokia’s acquisition of Gainspeed last year. At the time, WOW said it was “well down the path" with testing and "preparing for deployment" of Gainspeed's vCCAP.

“Nokia is revolutionizing the cable industry with an innovative new cable solution that gives operators the flexibility to implement a distributed access architecture without being handcuffed to a specific approach,” Cash Hagen, WOW’s chief operations officer, said the release issued Monday. “Virtualizing the DAA not only simplifies the network and drives cost savings, it also allows us to accelerate the delivery of new services that ultimately provide a better customer experience.”