DTAs’ role in the cable operator environment becomes more prominent.

In the family of customer premises equipment (CPE), digital transport adapters (DTAs) may lack cachet when compared with the latest set-top boxes, DVRs and gateways, but DTAs are playing an increasingly important role in cable operator deployments.

After working on its own specs with vendors such as Motorola and Cisco, Comcast is the poster child for deploying standard-definition DTAs in order to reclaim bandwidth by converting analog channels to digital. Mediacom Communications and WideOpenWest, to name a few, have also deployed DTAs, while Time Warner Cable, a big proponent of switched digital video (SDV), launched its first DTA pilot program in Maine earlier this year.

“For us, if you go back to the original intent of the DTA program, we needed a device that allowed analog glass [TVs] to see digital services,” said Comcast’s Steve Reynolds, senior vice president of CPE and home networking. “We wanted to move to an environment where we could transmit all of our services digitally using MPEG-2 compression, but there were millions, and it turns out tens of millions, of NTSC analog TVs out there that the customers had connected to our network.

“Obviously those devices have no ability to receive a digital signal, so we needed to come up with a device that could do that, and that’s where this original notion of this transport adapter came from.”

To date, Comcast has deployed more than 25 million DTAs and used the reclaimed bandwidth to spur the launch of its DOCSIS 3.0-based services and add in more HD offerings to its subscribers, among other items.

There were also operational benefits to deploying SD DTAs.

“There’s certainly some benefits from the fact that we have the ability to activate and deactivate the boxes remotely,” Reynolds said. “In years gone by when we had customers who were attached to analog outlets, the only way to do a connect or disconnect was to do a physical truck roll to connect services or put in traps to limit the service that the customer has through frequency traps.

“One of the great things about the DTA program, and about having that device in the premise, is it’s controlled through the same conditional access (CA) controllers that we have in place today. In Motorola, it’s the DAC, and in the Cisco networks, it’s a thing called a DTAC, which is a subsystem of the DNCS. All of those DTA devices have a unique address, and therefore from that control system, we’re able to send messages directly to that DTA, including activate and deactivate, which gives us the ability to do what we call soft connect.”

HD DTAs step up to the plate
From an inauspicious start as a low-cost, one-way, channel-zapping device for analog TVs, DTAs have evolved into more complex devices that are capable of working in various environments.

Comcast is conducting a large-scale trial of HD DTAs and plans on deploying them in subscribers’ homes later this year. Reynolds said that the HD DTAs represent the last piece of its analog-to-digital conversion, which is known internally as “Project Cavalry.” Comcast expects to have the all-digital project wrapped up by the end of next year, which includes the rollout of HD DTAs from vendors such as Pace, Technicolor, Motorola and Evolution Digital.

“We have been in field trials for a number of months, and the technology is working well, and all of the devices are stable, so all systems look good,” Reynolds said.

Evolution Digital's Brent SmithEvolution Digital President Brent Smith said that HD DTAs could be used by smaller cable operators that want to offer an entry-level HD service without using expensive set-top boxes, or to provision second, third and fourth TVs in a home.

Reynolds and Smith both pointed out that analog TVs are largely no longer available in the United States, but HD DTAs allow customers to access HD signals without the frills of VOD, pay-per-view or more expensive equipment in the home. By using an HDMI connection, customers can opt for an analog-type viewing experience on their new HDTVs through the use of HD DTAs.

“It turns out that HDMI is a great way for us to do an install,” Reynolds said. “It’s very simple, it’s one cable, it’s a broadly adopted standard and all of the CE devices support it. It’s an easy way for us to do an install, and, in particular, it’s an easy way for us to enable self-installs by the customer. So that was really why we moved to the HD device, which was to support these newer HD sets and, of course, the move to HD picture quality, which we think is going to be great too.

“We also think our customers will appreciate getting the HD local services that we offer through the basic tier through the DTA devices.”

BendBroadband and Cable One have also signed on to use HD DTAs in their footprints with Evolution Digital and Nagra, respectively.

BendBroadband is using HD universal DTAs (uDTAs) to serve the hospitality market in its Bend, Ore., system. BendBroadband is using wall plate DTAs from Evolution that fit over the cable junction boxes. Evolution’s HD uDTAs were designed to work with both Motorola and Cisco headends, and BendBroadband was the first cable operator to install them.

Evolution Digital's Liberty HD uDTA“Building the box was less of a challenge,” Smith said. “Making sure the box could operate in a standard implementation by Cisco or Moto was the bigger piece because there was more effort required to upgrade the control systems, to support it, and also some additional security levels which needed to be put in place.

“The hardware wasn’t the long pole in the tent; it was more the integration piece. Now we have a viable option for most operators to choose between SD and HD, whether it’s for bandwidth reclamation or offering lower-cost HD tiers.”

While the concept of HD DTAs has been around for a while, the cost needed to get down to a price point that would get cable operators to bite. Thanks to new chipsets, HD DTAs go for roughly $50 each in high volumes.

“When we started, we were looking at much heavier hospitality-specific products that were really designed to provide all of the functions and features that the hospitality industry may want, but when we got down to it, price became very important to those customers, and many of them had other methods to meet the needs of things like check in/check out,” said BendBroadband CTO Wade Holmes. “What really became important was HD for their sets and a low-cost device to connect them. Their preference was that it not be a two-way box because they didn’t want to create processes and procedures. They wanted to eliminate the guide, and they wanted it to be extremely simple to use.Nagra's HD DTA

“The DTA was a perfect fit for us. Keeping it small and low-cost were some of the things we were really battling against when we were trying to find the right solution for the hospitality market. Evolution did a good job of looking at what the customer need was.”

Reynolds said Comcast was also interested in using Evolution’s wall plate HD DTA for hospitality deployments, multi-dwelling units, and bars and restaurants.

“It would be a device that is permanently installed, so there would be no intention of sending those devices out to customers for self-install, for example,” Reynolds said. “The device would be installed in the unit, and it would remain installed on a move in/move out basis, or in a hospitality situation, it would remain in the hotel room or campus environment.

“We do the same things for other commercial accounts. You can go into bars and restaurants, and there are DTAs in there. Health clubs have actually been one of the areas where we’ve deployed a lot of DTAs. They use an IR blaster technology to control the DTAs. If they’re screen-mounted on an elliptical trainer or on a stationary bike, they’ll just use a DTA on a one-per-one basis.”

Breaking up the duopoly
DTAs can also help break up the Motorola and Cisco duopoly by offering an alternative that costs less, according to Tom Wirth, senior vice president of Nagra Americas.

Nagra's Tom Wirth“What we’re pitching is that a lot of operators can move away from the legacy duopoly and go with a new CAS (conditional access system),” Wirth said. “That opens us up to all kinds of things. Not only can you get DTAs from all kinds of manufacturers, including Asian manufacturers, but then you can start to look at more innovative products in the network as a whole, and you don’t have to go through the two legacy vendors’ CASs and kind of wait for them to deploy and come up with a product strategy.

“We were the first to have an HD DTA in the field with some of our partners, and we did all of the software and the CA systems. I think we were at least nine months ahead of the legacy CA in that area.”

Wirth said that in addition to being able to offer HD services, HD DTAs are somewhat future-proof since they support MPEG-4.

“The advantages with the new chipsets and the price point are you not only get to HD, but you get MPEG-4 in the network, which has a huge efficiency factor,” Wirth said. “The DTA is a good sweet spot for an operator to start to move from analog to digital. The problem is that if you looked a couple of years ago at the price point for MPEG-4, it was probably prohibitive, but now it’s not.”

The future is bright for DTAs
Work is currently underway on the next generation of DTAs, which includes the addition of an Ethernet port. E-DTAs could solve the encryption problem for companies such as Boxee, even if the Federal Communications Commission allows cable operators to encrypt their basic tiers. Reynolds said that while E-DTAs are still in the planning stages, they could be available by early next year.

From its humble beginnings, the DTA has transitioned into a more prominent member of cable operators’ CPE family, and it looks to have a long lifespan, as well.

“We will certainly continue to push forward on the technology of the DTA to make them smaller, more powerful and figure out ways to make them more energy-efficient. All of those good initiatives we have in place,” Reynolds said. “The DTA has become an ongoing part of our product line, and we’ll continue to support the DTA for many years to come.”

Evolution, Rovi join forces on adding feature-rich guide to DTAs
While providing a low-cost viewing option for subscribers and businesses is one of the key form factors of a DTA, ease of use is critical to the viewing experience.

On that note, Evolution Digital is working in tandem with Rovi on adding the latter’s electronic programming guide into its SD and HD DTAs.

Rovi guide
Evolution Digital is the first announced customer for the Rovi DTA Guide that was introduced last year at the SCTE Cable-Tec Expo in Atlanta.

As part of its all-digital conversion project, Comcast has championed the use of the low-cost DTAs to reclaim bandwidth that can subsequently be used for additional services, such as DOCSIS 3.0, or more features, such as adding more HD channels.

“We’ve always been major proponents of putting more functionality on the DTA,” said Evolution Digital President Brent Smith. “It’s one thing when you have 40 or 50 channels and you can zap through them, but it’s another thing, especially with HD, with potentially hundreds of channels. People’s expectations are, ‘I want to know what’s on, when it’s on,’ and so forth.

“We discussed this with Rovi and explained what we were doing and why we think it’s a good idea for DTAs. They were enthusiastic about it, and they have plans to have a full Rovi program guide embedded into our DTAs.”

Currently, Evolution has a “now and next” user interface (UI) embedded on its SD DTAs and HD uDTAs. The current UI allows viewers to go through channels to see what’s on now and what’s on next with basic descriptions of the programming.

The Rovi DTA Guide, which will come in HD and SD flavors, brings many more digital-like features to the viewers’ living rooms. It has parental controls and supports both English and Spanish languages, and it also features a “now and next” function.

“It’s a very elegant guide that provides 24 hours of listings data,” said Sharon Metz, Rovi’s vice president of vertical marketing for service providers. “It enables the consumer to see what’s on the full, generally digital lineup, typically about 77 to 80 channels, and provides descriptive information on the programs.

“What’s unique about the guide is that you have the full-feature grid and descriptive information on programming, but you also have a now/next banner that lets you browse while you watch TV and lets you see what’s on. It’s really a great opportunity to extend the interactive program guide experience into homes that wouldn’t normally have that kind of capability.”

In addition to the now and next UI, Evolution also provides an electronic program guide server that operators use to deliver the guide data to the DTAs. When the Rovi DTA Guide becomes available, operators that have a relationship with Rovi can send software updates to the DTAs in customers’ homes to download and launch the new Rovi DTA Guide on Evolution’s DTAs. The Rovi DTA Guide uses components of EBIF technology to deliver the application and data and render the guide onscreen.

Rovi isn’t saying when the guide will be commercially available, but Rovi’s press release from Expo last year said that an SD version of the DTA guide would first be launched in Latin America, which is a good fit due to the larger number of analog TV subscribers in some regions.

As far as other DTA vendors, which include Pace, Motorola, Cisco and Technicolor, Metz said there was some integration work to be done, but the flexibly of the guide would support multiple vendors.

“The expectation that we have is that everyone wants to have a guide on a DTA product, and we’re making that possible for our customers,” Rovi’s Metz said. “As we look at our historical information on how consumers value the guide experience, their passion to be able to quickly find out what’s on the TV and tune quickly from the guide and things like that, we think this is a great way to extend additional value into subscribers’ homes that never had digital service.”

Comcast’s Steve Reynolds, senior vice president of CPE and home networking, said Comcast has worked on a user guide with Rovi, which is known internally as “Atom,” and that is has been demonstrated at several trade show conferences this year by vendors.

SD DTA bandwidth savings
By deploying SD DTAs, cable operators can reclaim between 250 MHz and 300 MHz in each system that goes all-digital. If a typical cable system has 79 analog channels, and the operator decides to move 59 of those channels to digital, while perhaps leaving 20 or so as a lifeline analog service for some select markets, it would reclaim 354 MHz.

Given 354 MHz of reclaimed spectrum in the example above – and the fact that, on average, 10 standard-definition MPEG-2 digital programs can be inserted into one 6 MHz slot – this yields enough bandwidth for nearly 590 channels.