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.” ■

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.

Momentum has been building for some time for the Distributed Access Architecture (DAA) and 2019 was expected to be the year it would start to scale in the market. This technology is expected to transform cable operators’ infrastructure to remediate the limitations caused by bandwidth capacity increases and to enable them to offer competitive services. However, the reality is quite different.

To date, the real field deployments of DAA are few and far between, and in the 4Q 2018 earnings calls, many vendors spoke of a temporary pause. What is going on?

The reality is that the market is in the process of crossing the proverbial chasm from hype to reality, from early adopters to mainstream adoption. This process is always difficult, but it is even more complicated in this case given the far-reaching implications of the DAA for operators’ networks and operating environments.

Some of the challenges with which operators are grappling:

• Immature specifications: DAA specifications, notably Remote-PHY (Remote-MACPHY specs are still in development), are recent; despite the tremendous effort the industry has put in developing them, no spec is ever comprehensive from day one, and as operators are going through their comprehensive test cycles, issues are being identified and addressed. This is time-consuming.
• Interoperability: The industry has been working diligently on interoperability, for example, with CableLabs’s Plugfests. But more remains to be done. With any new specification there is often room for interpretation by vendors, which creates incompatibility and can hamper interoperability. It’s not a coincidence that early field deployments of DAA (of note is the Stofa recent field introduction) were largely based on one vendor’s solutions (in this case Arris). To its credit, the industry remains committed to interoperability and CableLabs continues to play a major role in this extensive undertaking.
• Need to support existing services: The DAA is profoundly different from the integrated architecture, and yet it has to support all existing services from day one. This requires considerable planning by operators.
• New operational environment: Despite the best efforts of vendors to maintain the operating environment with the DAA-based new solutions, the reality is that underlying the DAA transition is a migration from analog to digital. This has significant operational implications. One case in point is the analog sweep systems for testing and troubleshooting, which are no longer adequate in the digital domain. Therefore, operators need new tools for RF-network alignment and for upstream quality assessment.
• New skill set needed: Because the DAA uses digital technology principles, operators need to retrain technicians on the new technologies and in some cases supplement their workforce with new talent.
• New interconnect network: With the CCAP functionality distributed, an interconnect network is required to connect the CCAP cores to the remote PHY devices (RPD) and to connect other elements of the distributed network. The current analog network is ill-suited for this task, and operators are in various phases of planning for a Converged Interconnect Network (CIN) to replace it. There are many design considerations for the CIN that the operator has to address, and it often requires that disparate teams work together to develop the right strategy, which may make it time consuming and may add organizational complexity.
• Selecting the right architecture: Although R-PHY is to date gaining more traction because its specifications are further along, some operators may decide that R-MACPHY is better suited for their network topology (at least in some areas) and may wait for more mature solutions from vendors.
• Some operators are more cautious: Although some operators are comfortable as early adopters and are willing to work out the bugs that invariably come with the privilege, others are more cautious and prefer to move when solutions are more mature and interoperable.
• To DAA or not to DAA: As promising as DAA is, it may not be the right solution in every case. For example, in some sparse rural areas where bandwidth utilization is not substantial, the business case for DAA may not work. Some areas will retain an I-CCAP with a long cascade of amplifiers for years to come.
• To virtualize or not to virtualize: One of the key benefits of DAA is that it opens the way for virtualization, which substantially increases agility and service velocity for operators and enables them to leverage the inherent attributes of software to improve their service delivery and management. There are already strong software-based solutions on the market. Although some operators see their DAA transition in phases where a hardware network element is retained in Phase 1 and replaced by a software-based solution in Phase 2, other operators are considering adopting a virtualized solution in Phase 1. Virtualization has even more profound implications and needs thorough planning by the operators.

Considering all the parameters operators must optimize, it is not surprising that DAA is taking longer for market introduction on a broad scale. Expecting it to scale any sooner fails to account for the significant complexities — and opportunities — involved in bringing such a far-reaching transformation in a mature network that is serving millions of subscribers. The road ahead will be exciting but challenging for cable operators and their vendors.

Although the new architecture will unlock significant new opportunities, the homogeneous networks of yesterday are a thing of the past. Vendors have to either create and nurture a variety of solutions or bet on one approach and hope it will prove to be a winning one. Buckle up, the ride may be turbulent, but it will be fun.

Liliane Offredo-Zreik is a principal analyst with ACG Research covering the cable industry and SD-WAN.

"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.

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.

Ahead of announcing its Q4 financial results later today, Arris said several of its MSO customers in North America and Europe are part of a first wave of operators that are deploying Gen 2 modules for the E6000, its flagship Converged Cable Access Platform.

The Gen 2 modules, announced last fall, enable MSOs to upgrade existing chassis with up to a 70% increase in headend service group density without eating up more rack space, Arris said. MSOs are also looking to those modules as they move ahead with gigabit services and move to distributed access architectures and remote PHY implementations.  

RELATED: Cable-Tec Expo: Arris Paves Path to Remote PHY

The Gen 2 modules consists of the Downstream Cable Access Module 2 (DCAM-2), the Upstream Cable Access Module 2 (UCAM-2), and the Router System Module 2 (RSM-2).

Customers that have started to roll out Gen 2 modules include Comcast, Grande Communications, TDS Telecom, WideOpenWest, Liwest (Austria), NOS Comunicações (Portugal), and Toya (Poland).

Arris also announced that Ruckus Networks, the wireless-focused company acquired late last year, has signed a global OEM deal with Dell EMC. That deal includes access points, controllers, and Ruckus’s Cloudpath secure network access software, which can support access for bring-your-own-device, guest user and IT-owned device scenarios.

The deal also includes access to Ruckus-made IoT and CBRS LTE products.

RELATED: CBRS Spectrum to Open Windows of Opportunity for Cable Ops

"The Dell EMC brand and market reach is complementary to our own and represents a significant path for growth for both companies across a range of vertical markets, including education, public infrastructure, the federal government and service providers,” Dan Rabinovitsj, president, Ruckus Networks, said in a statement.

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

WideOpenWest announced that it has begun to deploy a new virtualized Distributed Access platform from Nokia as it looks to mine more capacity from its HFC network in certain scenarios.

WOW isn’t going for a wholesale move…at least not yet. Early on, WOW has identified some legacy brownfield markets (in Chicago and Cleveland, Ohio, according to Light Reading) where it will use Nokia’s Unified Cable Access platform (including the Gainspeed Controller and Gainspeed SC-2D Access Node and Gainspeed Video Engine) to help it pack on more capacity.

RELATED: Nokia Touts Versatility With Virtualized Distributed Platform for Cable Operators

“We have a couple of markets where we’re launching [Nokia] in locations where we are at exhaust on particular nodes and particular CMTSs [cable modem termination systems,” Cash Hagen, WOW’s chief operations officer, said. “The initial deployment allows us to go in and get immediate relief for those…Ultimately, the goal is to get to a point where this proves itself out and potentially could be [used] on a go-forward basis.”

WOW has been rolling out 1-Gig service on HFC using DOCSIS 3.1 and Arris E6000 CCAP chassis.

Hagen stressed that the work with Nokia isn’t a test or a trial, as WOW has had the company’s equipment (initially from Gainspeed, a startup acquired by Nokia last year) on its network for about two and a half years.

“It’s been through the paces…and we’re ready to go,” he said, adding that WOW plans to identify more brownfields to deploy Nokia’s solution next year, as well as some greenfield opportunities.

Though WOW’s DAA-focused work centers on fidelity and capacity gains as utilization of the DOCSIS network continues to rise and as the operator continues to split nodes and shrink down the size of individual service group, Hagen said a secondary benefit will be the relief it gives for power and space requirements at the headend.

Nokia’s new platform can run in Remote PHY or Remote MAC/PHY mode, as functionality has been reduced to a software element. Hagen said WOW is in the Remote MAC/PHY camp.

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.”

The “remote PHY” era is fully underway as two top cable access network suppliers – Arris and Cisco Systems – touted next-gen products that aim to help operators boost capacity while also keeping headend power and space requirements in check.

Both vendors touted their latest wares in conjunction with this week’s ANGA Com show in Cologne, Germany.

Arris’s approach uses the MAC core of its flagship converged cable access platform, the E6000, in tandem with new remote PHY modules that reside in the nodes. It’s also releasing a remote PHY shelf that’s targeted to smaller cable operators.

Arris also announced that Stofa, a Danish service provider, has tapped the vendor to migrate all its sites to DOCSIS 3.1 and a new distributed architecture that leans on the E6000 and Arris’s NC2000 nodes with the aforementioned remote PHY modules.

Cisco, meanwhile, launched “Infinite Broadband,” a remote PHY solution for cable operators that builds on its cBR-8 CCAP and GS7000 node products, noting that the combo establishes the “foundation” for virtualization and Full Duplex DOCSIS, an emerging annex to DOCSIS 3.1 that will enable symmetrical gigabit speeds on the HFC network.

RELATED: Cisco Chips In For ‘Full Duplex’ DOCSIS

Cisco said it RPHY has been shipping to customers in multiple countries since April 2017. Execs with Comcast, Cox Communications, and Liberty Global were referenced in Cisco’s RPHY announcement.

Update: Casa Systems, a vendor that competes with Arris and Cisco in the CCAP sector, announced Tuesday that it would demonstrate its DOCSIS 3.1 remote PHY solution at this week’s show.

Cisco also noted that its RPHY solution is based on “open, standardized software” contributed to the CableLabs OpenRPD forum in 2016 that, it claims, will create an interoperable ecosystem for remote PHY device vendors. Cisco said it’s also planning to provide interop testing for those vendors, with Vector Technologies, BKtel networks and Teleste already on board.

Cisco, Arris and other cable access network vendors are focusing on remote PHY as the architecture continues to become a bigger priority for cable operators. According to a recent survey of 35 cable operators around the globe conducted by Kagan Research, 61% of those MSOs said they plan to start virtualizing their CCAPs or begin the shift to a distributed access architecture (DAA) by the end of 2018.

RELATED: Cable Ops Poised for Push into Virtualization, Distributed Architectures

Arris expects remote PHY orders to start picking up toward Q4 with a commercial ramp up anticipated by the start of 2018, Dan Whalen, president of Arris’s Network & Cloud unit, said, noting that it pushes some of the space and power challenges faced by cable operators into the node while also paving the way for more capacity.

"We think the ramp starts next year,” Whalen said.

Arris, he added, is also pursuing a remote MAC/PHY strategy that could be ready to take hold by mid-2018, but acknowledged that there are some concerns about how much power consumption will be required inside the node to support both the MAC and the PHY.

The move to distributed architectures also create a more Ethernet-centric, open network, explained Daniel Etman, product marketing director for Cisco’s Cable Access Business Unit.

Cisco, he added, is also factoring in a new set of auto-configuration tools that enable field techs to update remote PHY nodes and enable operators to start to pivot to more distributed architectures.